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Mitigation of vessel-strike mortality of endangered Bryde’s whales in the Hauraki Gulf, New Zealand
... Large whales, including humpback whales (Megaptera novaeangliae) are more susceptible to collisions in areas where their habitat overlaps with heavy vessel traffic. This risk is increased when whales are resting or moving slowly at the surface (Constantine et al., 2015;Laist et al., 2001;Vanderlaan and Taggart, 2007). ...
... As such, vessel speed restrictions are being used as mitigation measures in various locations (e.g. USA: Gulf of Maine and Glacier Bay, Alaska; New Zealand: Hauraki Gulf, Auckland) to reduce the occurrence and/or severity of whale-vessel collisions with large whale species (Constantine et al., 2015;Gende et al., 2011;Vanderlaan et al., 2009). Combining information on the rate of near collisions with the severity (Vanderlaan et al., 2009) of whale vessel collisions based on differing vessel speeds provides insight into the efficacy of speed restrictions as a management tool. ...
... Although data were collected within the four-island region, results from previous literature (Constantine et al., 2015;Currie et al., 2014;Guzman et al., 2013;Laist et al., 2014;Lammers et al., 2013;Richardson et al., 2011;Stack et al., 2013;van der Hoop et al., 2014;Vanderlaan and Taggart, 2007) suggest implementation of a 12-13kts (6.2-6.7m/s) speed limit is warranted in areas and/or in seasons with high densities of humpback whales. ...
Increasing whale populations and vessel traffic worldwide has led to an increase in reported whale-vessel collisions. This paper reports on factors that affect the rate of whale-vessel collisions in the four-island region of Maui, Hawai’i. More specifically, it aims at quantifying the probability of a whale-vessel collision with varying vessel speeds using encounter distances as a proxy. A change point model was used to identify a speed threshold of 12.5kts (6.4m/s), which showed a significant change in the relationship between speed and mean sighting distance. A 3.4-fold decrease in close encounters with humpback whales was observed when vessels travelled at speeds of 12.5kts (6.4m/s) or less. Furthermore, results indicate that lone adult whales and calves are the most likely to be involved in a collision. A speed limit of 12.5kts (6.4m/s) is warranted in areas and/or during seasons where a high density of whales occurs. This limit aligns with a reduction in lethal vessel strikes with speed from previous studies which found a significant increase in the likelihood of mortality when vessel speed exceeds 12kts.
... Bryde's whales are active animals and prefer to swim in the upper water layer, especially within one or two body lengths (body length approximately 13.0 m for adult) from the surface (Constantine et al., 2015). Bryde's whales in the Hauraki Gulf of New Zealand, where water depths are approximately 50 m spent most of their time within approximately one adult body length from the surface and spent 73% and 91% of their dive time at a water depth less than 8.5 m and 14 m, respectively (Constantine et al., 2015). ...
... Bryde's whales are active animals and prefer to swim in the upper water layer, especially within one or two body lengths (body length approximately 13.0 m for adult) from the surface (Constantine et al., 2015). Bryde's whales in the Hauraki Gulf of New Zealand, where water depths are approximately 50 m spent most of their time within approximately one adult body length from the surface and spent 73% and 91% of their dive time at a water depth less than 8.5 m and 14 m, respectively (Constantine et al., 2015). In addition, the mean dive depth was 7 m (5%-95% range: 2-16 m) (Constantine et al., 2015). ...
... Bryde's whales in the Hauraki Gulf of New Zealand, where water depths are approximately 50 m spent most of their time within approximately one adult body length from the surface and spent 73% and 91% of their dive time at a water depth less than 8.5 m and 14 m, respectively (Constantine et al., 2015). In addition, the mean dive depth was 7 m (5%-95% range: 2-16 m) (Constantine et al., 2015). In the current study, calls recorded on the shallowest element of the vertical array had the lowest SPLs compared to those on the other three. ...
Presence of Bryde’s whales (Balaenoptera edeni) in the Beibu Gulf, China has been reported since 2016. In the current study, in situ Bryde's whale vocalizations were recorded. Bouts of frequency modulated repetitive and diversified calls were recorded. Repetitive calls were recorded when 1-3 whales were present within 2 km of the boat and were probably emitted by a single whale and functioned as contact calls. Repetitive calls were divided into biphonation downswept tonals and downswept tonals. Diversified calls were recorded when 4-7 whales were present within 2 km of the boat and were probably associated with acoustic exchanges between or among conspecifics. Diversified calls occasionally contained inflection points, frequency jumps, and break point features. The frequency band of Bryde's whale vocalizations overlapped highly with background noise. Most vocalizations in the current study were different than those previously reported for this species. Therefore, the findings of this study provide more information on the known acoustic repertoire of Bryde's whales and provide a basis for noninvasive monitoring of Bryde's whale with passive acoustic methods and for developing mitigation and conservation protocols to ensure their future viability.
... However, in recent years, the north Atlantic right whale population has been in decline and vessel strikes remain a serious threat to the species (Pace et al., 2017). To date, while some voluntary programs have shown signs of increasing cooperation (e.g., Constantine et al., 2015), most other voluntary VSRs have been ineffective (McKenna et al., 2012;Laist et al., 2014;Freedman et al., 2017). As one of the few tools to decrease vessel strike deaths, speed reductions, both mandated and voluntary, have now been used around the world from New Zealand to Panama to the Mediterranean to the Pacific coast of North America (Louzao et al., 2009;Constantine et al., 2015;Freedman et al., 2017;Guzman et al., 2020;Rockwood et al., 2020b). ...
... To date, while some voluntary programs have shown signs of increasing cooperation (e.g., Constantine et al., 2015), most other voluntary VSRs have been ineffective (McKenna et al., 2012;Laist et al., 2014;Freedman et al., 2017). As one of the few tools to decrease vessel strike deaths, speed reductions, both mandated and voluntary, have now been used around the world from New Zealand to Panama to the Mediterranean to the Pacific coast of North America (Louzao et al., 2009;Constantine et al., 2015;Freedman et al., 2017;Guzman et al., 2020;Rockwood et al., 2020b). ...
... A lack of cooperation with voluntary VSR measures has been common (Wiley et al., 2008;Silber et al., 2012a;Freedman et al., 2017;Guzman et al., 2020), though progress has been made in some cases (Constantine et al., 2015;Moore et al., 2018;Rockwood et al., 2020a). In contrast, noteworthy increases in compliance occurred after right whale protections on the East Coast were made mandatory (Lagueux et al., 2011;Silber et al., 2014). ...
Vessel strikes have been documented around the world and frequently figure as a top human cause of large whale mortality. The shipping lanes in the Santa Barbara Channel, California and nearby waters have some of the highest predicted whale mortality from vessel strikes in the United States waters of the eastern Pacific. Beginning in 2007, National Oceanographic and Atmospheric Administration requested voluntary vessel speed reductions (VSRs) for vessels greater than 300 GT traveling in the Santa Barbara Channel shipping routes to decrease whale mortality from ship strikes. We employed a ship strike model using whale density data and automatic identification system (AIS) vessel data to estimate mortality under several management scenarios. To assess the effect of the VSR on strike mortality, we bootstrapped speeds from vessels greater than 19 m long that transited when no VSR was in place. Finally, we calculated the predicted mortality for hypothetical cooperation scenarios by artificially adding speed caps post-hoc to real vessel transits. For 2012–2018, we estimated that in our study area on average during summer/fall (June–November) 8.9 blue, 4.6 humpback, and 9.7 fin whales were killed from ship strikes each year (13–26% greater than previously estimated). We evaluated winter/spring (January–April) humpback mortality for the first time, resulting in an estimate of 5.7 deaths on average per year. Poor cooperation with the VSR led to low (5% maximum) to no reductions in the estimated number of strike mortalities. Evaluating potential scenarios showed that if 95% cooperation occurred in the lanes, whale deaths there would decrease by 22–26%. Adding VSRs with similar cooperation levels at the northern end of the Santa Barbara Channel and south of Channel Islands National Marine Sanctuary could decrease estimated strike mortalities in those areas by 30%. If VSRs were added and cooperation reached 95% there and in the lanes, we estimate a 21–29% decrease in vessel strike mortalities could be attained relative to estimated mortality in the entire study area. To decrease the vessel strike related whale mortalities in this region, we recommend expanding the VSR areas and increasing cooperation voluntarily, or considering mandatory speed limits if desired cooperation levels cannot otherwise be met.
... Combined, these factors contribute to an evergrowing threat to whale survival. Many authors highlight that the level of threat in certain areas put at risk the populations' survival (e.g., Mediterranean fin whales (Balaenoptera physalus) and sperm whales (Physeter macrocephalus), New Zealand Bryde's whales (Balaenoptera edeni) ;Constantine et al., 2015;Fais et al., 2016;Panigada et al., 2006). The most illustrative case remains the North Atlantic right whales (Eubalaena glacialis). ...
... The North Atlantic right whales case is a good illustration of the processing of several parameters to achieve a successful interdisciplinary approach Tress and Fry, 2005). Constantine et al. (2015) also proved that the implication of the Protected Areas (ICMMPA), a more holistic approach to reducing the risk of collision between ships and whales, for instance, through risk assessment, is needed. One such way to standardize these assessments is the Formal Safety Assessment (FSA) used by the International Maritime ...
... While whale-ship collision mitigation solutions have been implemented for two decades, a recent push towards international regulatory management of collisions has been published in the literature G. K. Silber et al., 2012). This thesis shows that, at the local and regional level, the compliance with, and the applied effectiveness of mitigation solutions is often low, with few exceptions (e.g., Constantine et al., 2015;. Compliance increases through the implementation of mandatory solutions -or incentives (Lagueux et al., 2011;McKenna et al., 2012). ...
Collisions with ships are one of the main modern threats to whale survival. Several solutions exist to reduce the risk of collision, but the compliance of the shipping industry with them is often limited. This interdisciplinary thesis aims at understanding the economic, logistic, and ecological gaps that hinder the shipping industry’s compliance. The research question is the following: How to integrate human and ecological dimensions in a standardized process to better manage whale-ship collisions? To answer this question, this thesis aims at (1) defining a standardized assessment process for mitigation solutions; (2) investigating the economic and logistic dimensions needed to achieve a holistic assessment of the whale-ship collision issue. The International Maritime Organization has the potential to improve whale protection from ship strikes, and we investigate its risk assessment framework, namely the Formal Safety Assessment. Based on the identified gap within this framework, our research first explores the notion of acceptable risk within the shipping industry and conservation science. Then, we investigate the preferences of the shipping industry for mitigation solutions, and study the economic benefits of avoiding collisions, through avoided costs and risk evaluation criterion. By creating a bridge between economics and ecology, this manuscript improves the mutual understanding of the shipping industry and conservation science. This work could be used as guidelines for the proposal of solutions, leading to an increased compliance of the shipping companies, and, therefore, an improved protection of whales.
... Marine wildlife can be killed or severely injured by the collision with the hull, outboard motor, or propeller of a marine vessel [27,42,46]. This can have negative consequences for the species and economic costs for the boaters [10,32]. The threat of wildlife mortality from collision with a vessel is influenced by the likelihood of collision and severity of the resulting trauma [27]. ...
... Therefore, information on boating/vessel use, boater perceptions, and willingness to accept vessel-strike reduction interventions is critical. Potential impacts of these interventions on human communities, and ways to mitigate undesirable impacts must also be considered in the decision-making process [10]. To inform potential conservation interventions to mitigate vessel strikes on sea turtles, we used expert-informed surveys of Florida boaters to gauge perceptions of potential conservation interventions in the St. Lucie Inlet, Florida, and surrounding waterways. ...
... Outreach and education can help to explain new interventions to members of the public, and to increase community awareness and buyin. Well-designed and locally tailored community engagement and education are key to community buy-in, support, and promotion of interventions [10,15,19,43]. Indeed, experts at the initial workshop emphasized that education, outreach, and awareness should be central to new efforts to reduce vessel strikes on sea turtles [44]. ...
Sea turtles and boating activities often occur in shared waters. This is problematic because sea turtles are susceptible to vessel strikes since they spend significant portions of their lives in nearshore shallow water to breathe, reproduce, and feed. Targeted conservation strategies are needed to reduce vessel strikes on sea turtles, and successful integration of stakeholder perspectives is necessary for conservation success. Here, we present results from a multi-step approach to investigate responses to potential conservation interventions for reducing vessel strikes on sea turtles. First, challenges and opportunities related to potential interventions that could be used to reduce sea turtle vessel strikes were discussed and assessed by a workshop of conservation and enforcement experts. Second, the workshop-identified interventions were incorporated into a survey questionnaire for recreational boaters. Third, this face-to-face survey was administered around the St. Lucie Inlet, an area identified as a vessel strike "hot spot" in Florida (USA). The questionnaire asked about boating preferences and practices, existing and potential conservation interventions, and sea turtle presence in the area. Respondents suggested that greater community support for implementation of interventions would be obtained if they (1) were voluntary rather than mandatory/legislated, (2) overlapped with existing interventions (e.g., if speed mitigation zones for sea turtles overlapped significantly with existing speed reduction zones for manatees) and/or added minimal new restrictions and inconveniences, and (3) were accompanied by explanatory materials on the need for, and the effectiveness of, such management strategies. Boater buy-in for management strategies and compliance can vary significantly. As such, our exploratory study should be replicated where proposed sea turtle conservation-related strategies might be warranted to ensure proper contextual fit. Boaters are a powerful, integral, and a growing demographic that must be effectively and respectfully engaged for effective sea turtle conservation in Florida and beyond.
... Over time, it is possible that vessel-related mortality might exceed the recruitment rate, either through contributing to a cumulative mortality rate (i.e., mortality from both natural and human-related causes) or on its own (e.g., Kraus et al., 2005;Guo, 2006;van der Hoop et al., 2013;Fais et al., 2016). For species such as North Atlantic right whales (Moore et al., 2004), Hauraki Gulf Bryde's whales (Balaenoptera edeni bryde, New Zealand: Constantine et al., 2015), North Pacific blue whales (Redfern et al., 2013;Rockwood et al., 2017), North Pacific humpback whales (Rockwood et al., 2017), North Pacific fin whales (Rockwood et al., 2017;Keen et al., 2019), and Canary Island sperm whales (Spain: Fais et al., 2016), tools like comprehensive ship strike reporting systems, stranding databases, and modeled risk analyses have helped to identify populations for which ship strike rates may exceed population recruitment rates. ...
... A wide variety of mitigation measures that aim to reduce the risk of collisions between vessels and marine animals exist today (e.g., Silber et al., 2012b;Couvat and Gambaiani, 2013;McWhinnie et al., 2018), most of which were developed with a focus on whales. The most suitable mitigation measure(s) depends on the geographic area, environmental conditions, vessels involved, species targeted, time-pressure to implement a mitigation measure, and cost of mitigation (e.g., Weinrich et al., 2010;Silber et al., 2012a;Constantine et al., 2015;McWhinnie et al., 2018). Below we list the mitigation measures that have been developed today and discuss whether they have been effective in the protection of whales as well as whether they could be applied to smaller marine species. ...
... Identifying and evaluating these types of programs for use on a wider scale or for other marine user groups is included in the latest IWC strategic plan (Cates et al., 2017). In New Zealand, a special Bryde's whale ship strike working group has been established to investigate and share information on the cause of ship strikes with Bryde's whales as well as to develop and discuss feasible mitigation measures (Constantine et al., 2015). This working group includes individuals from industry, government, academic institutions, non-government organizations, and local Mãori tribes. ...
Concern about the effects of maritime vessel collisions with marine animals is increasing worldwide. To date, most scientific publications on this topic have focused on the collisions between large vessels and large whales. However, our review found that at least 75 marine species are affected, including smaller whales, dolphins, porpoises, dugongs, manatees, whale sharks, sharks, seals, sea otters, sea turtles, penguins, and fish. Collision incidents with smaller species are scarce, likely as a result of reporting biases. Some of these biases can be addressed through the establishment of species-specific necropsy protocols to ensure reliable identification of collision-related injury, particularly blunt force trauma. In addition, creating a ship strike database for smaller species can assist in identifying the species most frequently involved in collisions, identifying high-risk areas, and determining species-specific relationships between vessel speed and lethal injury. The International Whaling Commission database on collisions with large whales provides a good example of this type of database and its potential uses. Prioritizing the establishment of a species-specific necropsy protocol and a database for smaller species as well as the identification of high-risk areas for species other than large whales, would be a valuable step toward the mitigation of collisions with smaller species.
... The Hauraki Gulf, New Zealand, is key habitat to one of the few known year-round populations of Bryde's whales in the world (Baker and Madon, 2007). Ship strike is a primary cause of whale mortality in the Gulf, with 85% of whale deaths definitely or most likely the result of injuries sustained during a collision (Constantine et al., 2015). Ship strike mortality is estimated to kill 2.4 Bryde's whales/year from 1996 to 2014; an unsustainable mortality rate for this small population (Tezanos-Pinto et al., 2017). ...
... This protocol introduced a range of voluntary mitigation measures designed to reduce the risk of ship strike to whales from the 1400-1500 ships that call into the port (e.g. POAL, 2013;Constantine et al., 2015). There were three key steps, 1) passage planning, which included a 10 kt speed limit, 2) the posting of a dedicated watch for whales during daylight hours, and 3) adherence to the Large Whale Warning System (LWWS), in which whale sightings are reported to Harbor Control, which then immediately broadcasts this information to vessels in the Gulf (POAL, 2013). ...
... We examined shipping traffic from vessels �70 m as large ships pose a greater risk of ship strike and the crew are less likely to notice if they collide with a whale (Laist et al., 2001;Jensen and Silber, 2003;Douglas et al., 2008). We acknowledge that small vessels pose some risk to whales (Laist et al., 2001) and there are two Bryde's whales in the Gulf with propeller wounds from a small vessel (Constantine et al., 2015), but to date no vessel, large or small, has reported a whale strike in the Gulf. There are low levels of smaller vessel traffic in the primary habitat of these whales (Hartill et al., 2011), most are not equipped with an AIS and unlike Wiley et al. (2011) there is little information on tonnage so we chose to use length as our metric as the data were more reliable. ...
Evidence-based policy, with proven efficacy, is key to the mitigation of human-wildlife conflict. Voluntary agreements to implement conservation actions can take less time to implement than mandatory policies. However, their efficacy is questionable as they rely on the awareness of the measures, cooperation, and goodwill of affected stakeholders. The aim of this study was to examine the efficacy of voluntary ship strike mitigation measures implemented in 2013 to protect a threatened, resident population of Bryde's whales (Balaenoptera edeni brydei) in the Hauraki Gulf, New Zealand. Automatic Identification System (AIS) and whale sightings data were used to determine the distribution and density of ships and whales throughout the Gulf to quantify and assess compliance to the voluntary 10 kt speed limit, and subsequently the risk of lethal ship strike to whales. From October 2014–September 2016, the location of 189 groups of whales and shipping routes of 703 vessels ≥70 m in length were plotted using ArcGIS. Hotspots of preferred whale habitat differed from 2010 to 2013, but shipping traffic density did not. Probability of lethal ship strike to whales in the Gulf has nearly halved (26%) since 2013 (51%) due to a reduction in average vessel speed from 13.2 kt to 10 kt. Observation and reporting systems developed to reduce potential ship strike events, were analysed at a fine scale using reporting rates and AIS data to measure the reactions of ships to real-time reports. Few whale sightings were reported to Harbor Control (n = 37; 8% shipping, 68% whale watch vessel, 24% other vessel types), and no ships diverted course to avoid reported whale locations. This study highlights the importance of testing the efficacy of conservation mitigation measures, as effective voluntary actions may provide a means to reduce the threat of ship strike to whales.
... Combined, these factors contribute to an ever-growing threat to whale survival. Many authors highlight that the level of threat in certain areas put at risk the populations' survival (e.g., Mediterranean fin whales (Balaenoptera physalus) and sperm whales (Physeter macrocephalus), New Zealand Bryde's whales (Balaenoptera edeni) [15][16][17]). The most illustrative case remains the North Atlantic right whales (Eubalaena glacialis). ...
... Indeed, the lack of a holistic view prevents the adoption of mitigation measures and has been used by shipping industries as an excuse not to act [5,29,30]. To be noted that some successful cases dealing with ship-whale collision have integrated a more holistic approach, leading to higher compliance of the shipping industry (e.g., Panama [31]), even engaging them in voluntary actions [17]. The North Atlantic right whales case is a good illustration of the processing of several parameters to achieve a successful interdisciplinary approach [24,32]. ...
... The North Atlantic right whales case is a good illustration of the processing of several parameters to achieve a successful interdisciplinary approach [24,32]. Constantine et al. [17], also proved that the implication of the shipping industry stakeholders in the New Zealand Bryde's whale collision issue could lean towards voluntary mitigation actions and engage the shipping industry toward social license [33]. ...
Ship strikes are one of the main human-induced threats to whale survival. A variety of measures have been used or proposed to reduce collisions and subsequent mortality of whales. These include operational measures, such as mandatory speed reduction, or technical ones, such as detection tools. There is, however, a lack of a systematic approach to assessing the various measures that can mitigate the risk of ship collisions with whales. In this paper, a holistic approach is proposed to evaluate mitigation measures based on a risk assessment framework that has been adopted by the International Maritime Organization (IMO), namely the Formal Safety Assessment (FSA). Formal Safety Assessment (FSA) is "a rational and systematic process for assessing the risk related to maritime safety and the protection of the marine environment and for evaluating the costs and benefits of IMO's options for reducing these risks". The paper conceptualizes the use of a systematic risk assessment methodology, namely the FSA, to assess measures to reduce the risk of collisions between ships and whales.
... The issue of masking has been widely discussed and recognised, with the International Maritime Organisation (IMO) adopting guidelines to reduce underwater noise from commercial ships (IMO, 2014) and the marine industry trialling mitigation strategies to reduce noise effects on sensitive marine life (Chion et al., 2017;Constantine et al., 2015;POAL, 2015;POV, 2017). Management of marine shipping has been discussed in an Arctic context by the Arctic Council (Arctic Council, 2015), with modification of vessel operations through areas of high marine mammal densities and vessel slowdowns being suggested as possible measures to mitigate vessel noise effects (Arctic Council, 2015;Chion et al., 2017;Huntington et al., 2015). ...
... Management of marine shipping has been discussed in an Arctic context by the Arctic Council (Arctic Council, 2015), with modification of vessel operations through areas of high marine mammal densities and vessel slowdowns being suggested as possible measures to mitigate vessel noise effects (Arctic Council, 2015;Chion et al., 2017;Huntington et al., 2015). Vessel slowdown is becoming increasingly attractive in areas where re-routing shipping corridors is not possible, particularly as it can also reduce the risk of ship strike (Chion et al., 2017;Constantine et al., 2015). Furthermore, slowing vessels reduces emitted noise levels and consequently decreases masking for marine mammals and fish (Putland et al., 2017). ...
... When re-routing shipping corridors is not possible, reducing vessel speeds through core marine mammal habitats may be the only alternative. The Ports of Vancouver (POV, 2017) and the Ports of Auckland (Constantine et al., 2015;POAL, 2015;Putland et al., 2017), have implemented voluntary slowdown trials in the past to reduce the risk of vessel strike and/or auditory masking. Recently, the benefits of speed restrictions for communication ranges in fish and marine mammals have been investigated (Putland et al., 2017). ...
Vessel slowdown may be an alternative mitigation option in regions where re-routing shipping corridors to avoid important marine mammal habitat is not possible. We investigated the potential relief in masking in marine mammals and fish from a 10 knot speed reduction of container and cruise ships. The mitigation effect from slower vessels was not equal between ambient sound conditions, species or vessel-type. Under quiet ambient conditions, a speed reduction from 25 to 15 knots resulted in smaller listening space reductions by 16–23%, 10–18%, 1–2%, 5–8% and 8% respectively for belugas, bowheads, bearded seals, ringed seals, and fish, depending on vessel-type. However, under noisy conditions, those savings were between 9 and 19% more, depending on the species. This was due to the differences in species' hearing sensitivities and the low ambient sound levels measured in the study region. Vessel slowdown could be an effective mitigation strategy for reducing masking.
... The issue of masking has been widely discussed and recognised, with the International Maritime Organisation (IMO) adopting guidelines to reduce underwater noise from commercial ships (IMO, 2014) and the marine industry trialling mitigation strategies to reduce noise effects on sensitive marine life (Chion et al., 2017;Constantine et al., 2015;POAL, 2015;POV, 2017). Management of marine shipping has been discussed in an Arctic context by the Arctic Council (Arctic Council, 2015), with modification of vessel operations through areas of high marine mammal densities and vessel slowdowns being suggested as possible measures to mitigate vessel noise effects (Arctic Council, 2015;Chion et al., 2017;Huntington et al., 2015). ...
... Management of marine shipping has been discussed in an Arctic context by the Arctic Council (Arctic Council, 2015), with modification of vessel operations through areas of high marine mammal densities and vessel slowdowns being suggested as possible measures to mitigate vessel noise effects (Arctic Council, 2015;Chion et al., 2017;Huntington et al., 2015). Vessel slowdown is becoming increasingly attractive in areas where re-routing shipping corridors is not possible, particularly as it can also reduce the risk of ship strike (Chion et al., 2017;Constantine et al., 2015). Furthermore, slowing vessels reduces emitted noise levels and consequently decreases masking for marine mammals and fish (Putland et al., 2017). ...
... When re-routing shipping corridors is not possible, reducing vessel speeds through core marine mammal habitats may be the only alternative. The Ports of Vancouver (POV, 2017) and the Ports of Auckland (Constantine et al., 2015;POAL, 2015;Putland et al., 2017), have implemented voluntary slowdown trials in the past to reduce the risk of vessel strike and/or auditory masking. Recently, the benefits of speed restrictions for communication ranges in fish and marine mammals have been investigated (Putland et al., 2017). ...
... With this in mind, the present study had two objectives: firstly, to establish baseline data on anthropogenic noise from commercial vessels throughout the Hauraki Gulf; secondly, to use this information to determine the effect of vessel noise on the communication space of bigeye, Pempheris adspersa, and Bryde's whales, Balaenoptera edeni. These two species are both residents of the Hauraki Gulf and communicate using sound (Constantine et al., 2015;van Oosterom et al., 2016;Radford, Ghazali, Jeffs, & Montgomery, 2015). Bryde's whales vocalize at a rate and frequency range similar to many other baleen whales (Moore, Stafford, Dahlheim, & Fox, 1998; Sirovi c, Hildebrand, Wiggins, & Thiele, 2009;Stafford, Mellinger, Moore, & Fox, 2007), suggesting ...
... The source level and hearing ability of bigeyes is known from laboratory experiments (Radford et al., 2013, which can be directly used in the Figure S1). were chosen to be in close proximity to the most traversed shipping routes into the Ports of Auckland (Constantine et al., 2015). At Horn Rock and Shearer Rock, hydrophones were attached to a weighted stand 1 m off the seafloor and retrieved by a diver. ...
... for Bryde's whales calculated over the frequency range 40-1,000 Hz by averaging data from various sources (Constantine et al., 2015;Cummings et al., 1986;Sirovi c et al., 2014); SPL is the background, transient or CPA SPL; TL sp is spherical spreading transmission loss, calculated as 20log(r) (Mann, 2006), where r is the range in metres, and DT is detection threshold, defined as the difference between the signal and background SPL where a signal can be perceived. ...
Anthropogenic noise across the world’s oceans threatens the ability of vocalizing marine species to communicate. Some species vocalize at key life stages or whilst foraging, and disruption to the acoustic habitat at these times could lead to adverse consequences at the population level. To explore the risk of such impacts, we investigated the effect of vessel noise on the communication space of the Bryde’s whale Balaenoptera edeni, an endangered species which vocalizes at low frequencies and bigeye Pempheris adspersa, a nocturnal fish species which uses contact calls to maintain group cohesion while foraging. By combining long-term acoustic monitoring data with AIS vessel-tracking data and acoustic propagation modelling, a quantitative method for determining the impact of vessel noise on their communication space was established. Routine vessel passages cut down communication space by up to 61.5% for bigeyes and 87.4% for Bryde’s whales. The influence of vessel noise on communication space also exceeded natural variability between 3.9 and 18.9% of the monitoring period. To combat potential effects of vessel sound, we propose the application or extension of ship speed restrictions in ecologically significant areas, since our results indicate a reduction in sound source levels for vessels transiting at lower speeds.
... Entanglements in fishery gear represent one of the greatest threats to large whale populations globally and in some instances have resulted in population level declines (Clapham et al. 1999;Thomas et al. 2016). Entanglements of Bryde's whales have been reported from a range of fisheries including: gillnets (Reeves et al. 2003;Moazzam and Nawaz 2017), pot/traps (Groom and Coughran 2012;Penry et al. 2016), longlines (Soldevilla et al. 2017, purse-seines (Berkenbusch et al. 2013;Escalle et al. 2015), and mussel aquaculture gear (Lloyd 2003;Constantine et al. 2015), as well as nonfishery related gear such as bather protection (anti-shark) nets (Meÿer et al. 2011). ...
... Vessel collisions involving Bryde's whales are most likely to occur in coastal populations that overlap with busy shipping lanes. In the Hauraki Gulf, New Zealand, where Bryde's whales have a nearshore distribution, mortality due to ship strike was assigned to 85% of Bryde's whale carcasses examined between 1996 and 2014 (Constantine et al. 2015). Growing numbers and intensity of shipping traffic will result in increased underwater noise levels that mask low frequency communication between whales (Putland et al. 2017). ...
This comprehensive species-specific chapter covers all aspects of the mammalian biology, including paleontology, physiology, genetics, reproduction and development, ecology, habitat, diet, mortality, and behavior.
The economic significance and management of mammals and future challenges for research and conservation are addressed as well.
The chapter includes a distribution map, a photograph of the animal, and a list of key literature.
... Compliance with conservation requirements is usually enhanced through knowledge sharing, collaborative planning processes between conservation agencies and shipping industries, as well as the enforcement of conservation measures [15,30,71]. Chion et al. [57] could demonstrate that a co-construction (bottom-up) approach between members of the maritime/industry authorities, governmental and non-governmental organizations, and scientists greatly enhanced commitment to voluntary speed limitations in the St. Lawrence Estuary (Quebec, Canada). ...
... Chion et al. [57] could demonstrate that a co-construction (bottom-up) approach between members of the maritime/industry authorities, governmental and non-governmental organizations, and scientists greatly enhanced commitment to voluntary speed limitations in the St. Lawrence Estuary (Quebec, Canada). Thus, engaging the Panamanian maritime sector and conservation authorities in concerted efforts to ensure safe and cost-effective shipping and concomitantly achieve conservation goals can contribute to better compliance [sensu [10,64,71]. This may involve education and outreach programs to inform mariners about speed limits and their crucial role for reducing whale-vessel collisions, but also consideration of operational requirements and constraints of marine industries during the implementation phase [10,72]. ...
To reduce the whale-vessel strike risk in the Gulf of Panama, the International Maritime Organization (IMO) adopted a Traffic Separation Scheme (TSS) with corresponding inshore traffic zones and seasonal (Aug–Nov) speed limits of ≤10 kn (Speed Over Ground, SOG) commencing December 2014. Here, we assessed compliance rates to these new regulations. Vessel traffic data in the area were obtained between 2014 (pre-TSS implementation) and 2016 using Automated Identification System (AIS) transponders. Most vessels (86.1 and 89.8% in 2015 and 2016, respectively) promptly adhered to the TSS. Significant differences were also detected in speed compliance rates among years, but overall speed compliance was low, i.e., only 19.0% of ships in 2015 and 9.7% in 2016 traveled at ≤10 kn. Compliance rates with the TSS and speed limits varied significantly by vessel type. These divergent compliance responses were likely due to inadequate communication to mariners and notes on printed and digital charts. Speed compliance could be enhanced, e.g. via education programs to raise awareness of endangered whales, along with collaborative initiatives between the maritime industry and port authorities, and law enforcement. In addition, continued monitoring of compliance with IMO regulations, as well as ship-related cetacean injuries/mortality by local environmental authorities should aid assessing the efficacy of these conservation measures and mitigating the whale-vessel strike risk in the Gulf of Panama. Above all though, authorities need to evaluate a mandatory speed regulation by the IMO or unilaterally, based on the newly modified and extended baseline for nation's internal waters.
... Scientific information should also be analyzed in conjunction with stakeholders, because research that is inclusive and balanced by a diversity of interests provides results that stakeholders view as more credible and acceptable (Wiley et al. 2013). One way to speed up the implementation of conservation measures is to develop a social process as early as possible (Constantine et al. 2015). Success stories associated with this approach include the Transit Protocol for Commercial Shipping, which protects whales from ship strikes in the Hauraki Gulf, New Zealand, and the shifting of the Boston Traffic Separation Scheme (BTSS) to protect whales from ship strikes in the Stellwagen Bank National Marine Sanctuary in the US (see "Best practices"). ...
... The Hauraki Gulf Transit Protocol for Commercial Shipping is an agreement between the Ports of Auckland (POAL) and the shipping industry. It is the outcome of collective efforts of the POAL, the commercial shipping industry, New Zealand's Department of Conservation (DOC), and Auckland University (Constantine et al. 2015), and contains reasonable and practical measures to reduce the number of whale deaths caused by vessels. Furthermore, though it is voluntary in nature (it consists of recommendations that have been agreed upon), the threat of ship strikes to the whale population has been shown to be vastly reduced due to the lowering of vessel speeds in the Hauraki Gulf (a recommendation of the protocol). ...
The present paper focuses on the importance of the ecosystem approach (EA) for the preservation and conservation of the marine environment. Marine ecosystems are complex entities that contribute significantly to the sustainable well being of people by providing a wide range of goods and services. The economic benefits of these goods and services are enormous and to a large extent impossible to estimate. Thus, due to the extensive and irrational use and overexploitation of marine resources, there is a need for an integrated, holistic, sustainable approach to marine environmental management. The EA requires a deep understanding of ecological, economic, societal, and cultural interactions and is the ultimate tool for implementing and achieving sustainable development. It is the key to balancing the number of users of marine resources and stakeholders in order to promote the roles of the green economy and (sustainable) blue growth (e.g., maritime activities, fisheries, renewable energy, and blue biotechnology). The aim is to use the EA to optimize the benefits provided by the oceans while simultaneously minimizing the pressures exerted by human activities on marine ecosystems.
... This was to acknowledge the variability in individual responses to different noise levels and sources. Others have found behavioral responses can depend on a number of covariates including an individual's prior experience to noise (Constantine et al., 2015), the habitat quality (Robertson et al., 2013), the distance from the sound source (Madsen et al., 2006;Dunlop et al., 2017), and perhaps by such factors as age, sexual condition, and gender (female killer whales seemed to be more likely than males to respond to the passage of a ship; Williams et al., 2014;Gomez et al., 2016). Context-specific dose-response functions with separate functions for different behavioral states (e.g., Ellison et al., 2012), could reduce uncertainty in the predicted behavioral effects, but such an approach would require increased understanding of these contexts (Harris et al., 2018). ...
... Understanding both the response and the variation in the response to commercial vessel disturbance is important both for assessing population consequences for SRKW and in management decisions. There are other examples of how consensus decision-making and sound science can be used to reduce the effect of marine shipping on whales in Canada (e.g., St. Lawrence estuary, the Bay of Fundy; Laist et al., 2014;Parrott et al., 2016), and internationally (e.g., Hauraki Gulf, New Zealand; Constantine et al., 2015). In this study, the use of spatially explicit models based on local data sources with transparent assumptions provided significant advantages over unsubstantiated opinion to the decision-making process by providing quantitative support in the form of maps and outputs (with both temporal and spatial variability) assessing the 'potential lost foraging time' in response to management decisions. ...
A voluntary commercial vessel slowdown trial was conducted through 16 nm of shipping lanes overlapping critical habitat of at-risk southern resident killer whales (SRKW) in the Salish Sea. From August 7 to October 6, 2017, the trial requested piloted vessels to slow to 11 knots speed-through-water. Analysis of AIS vessel tracking data showed that 350 of 951 (37%) piloted transits achieved this target speed, 421 of 951 (44%) transits achieved speeds within one knot of this target (i.e., ≤12 knots), and 55% achieved speeds ≤ 13 knots. Slowdown results were compared to ‘Baseline’ noise of the same region, matched across lunar months. A local hydrophone listening station in Lime Kiln State Park, 2.3 km from the shipping lane, recorded 1.2 dB reductions in median broadband noise (10–100,000 Hz, rms) compared to the Baseline period, despite longer transit. The median reduction was 2.5 dB when filtering only for periods when commercial vessels were within 6 km radius of Lime Kiln. The reductions were highest in the 1st decade band (-3.1 dB, 10–100 Hz) and lowest in the 4th decade band (-0.3 dB reduction, 10–100 kHz). A regional vessel noise model predicted noise for a range of traffic volume and vessel speed scenarios for a 1133 km2 ‘Slowdown region’ containing the 16 nm of shipping lanes. A temporally and spatially explicit simulation model evaluated the changes in traffic volume and speed on SRKW in their foraging habitat within this Slowdown region. The model tracked the number and magnitude of noise-exposure events that impacted each of 78 (simulated) SRKW across different traffic scenarios. These disturbance metrics were simplified to a cumulative effect termed ‘potential lost foraging time’ that corresponded to the sum of disturbance events described by assumptions of time that whales could not forage due to noise disturbance. The model predicted that the voluntary Slowdown trial achieved 22% reduction in ‘potential lost foraging time’ for SRKW, with 40% reductions under 100% 11-knot participation. Slower vessel speeds reduced underwater noise in the Slowdown area despite longer passage times and therefore suggest this is an effective way to benefit SRKW habitat function in the vicinity of shipping lanes.
... Here we investigate the resting behavior of Bryde's whale in an area of dense vessel traffic, the Hauraki Gulf, where resting behavior may enhance risk of ship strike for these whales (Constantine et al. 2015). The Hauraki Gulf is a large bay with depths around 50 m, located on the north east coast of New Zealand (Paul 1968). ...
... As it affects their level of consciousness, it makes them more vulnerable to predators and human-related threats such as vessel strikes. This may explain the high level of ship strike mortality found in the Hauraki Gulf (Constantine et al. 2015) prior to voluntary mitigation measures were established. Thus, having a better understanding of Bryde's whale resting behavior enables a better understanding of their ecology and effective conservation action planning. ...
Many animals require intervals of rest or sleep in which their vigilance level is reduced. For marine fauna, including large baleen whales, resting potentially increases the risk of predation and vessel-strike. However, there is scarce information about how, and how often, whales rest which makes it difficult to assess the severity of this risk. Here we examine resting patterns of Bryde’s whales (Baleaenoptera edeni/brydei), using data collected by sound and movement archival tags (DTAGs) deployed on four whales in the Hauraki Gulf, New Zealand. To identify low activity levels associated with resting, we used RMS jerk and mean flow noise (as proxies for activity and speed, respectively), as well as changes in dive patterns (dive depth and shape), fluking, and respiration rates. The tagged whales showed strong diel differences in behavior with long periods of low activity consistent with resting occurring exclusively during the night. This pattern indicates that either (i) Bryde’s whales rely on senses that are less effective in the dark to locate prey, or (ii) that prey aggregate less densely at night, making foraging less efficient. Thus, Bryde’s whales conserve energy through rest during times when the net benefit of foraging effort is low. However, by reducing their interaction level with their environment, night-time resting also makes Bryde’s whales more vulnerable to vessel strikes, an important source of mortality for cetaceans.
Significant statement
All mammals need to rest periodically and whales are no exception. But while resting land mammals can be observed directly, little is known about when and how whales rest; even though lower vigilance levels during resting could make them more vulnerable to threats such as collisions with boat traffic. We used sound and movement logging tags on resident Bryde’s whales in a busy gulf to study their daily activity patterns. We found that, while whales were active during daytime making energetic lunges to capture tonnes of plankton, they dedicated much of the night to rest. This suggests that whales may rely on vision to find prey or that prey are less densely aggregated at night making foraging less efficient. However, this near-surface resting behavior which may also be shared by the other giant baleen whales increases the risk of ship strikes.
... Vehicle impacts, however, are not limited to the terrestrial realm, and are similarly widespread in the marine realm (Laist et al., 2001). Marine vessels have frequently been documented colliding with marine animals, large whales (cetaceans) in particular, and these collisions are termed vessel strikes (or ship strikes) (Constantine et al., 2015;Douglas et al., 2008;Vanderlaan and Taggart, 2009). Advances in vessel propulsion technology over the 20th century resulted in faster vessels, paired with the increased number of vessels in the global fleet, has been correlated with an increased number of documented vessel strikes to large cetaceans (Laist et al., 2001). ...
Collisions between vehicles and wildlife is a global conservation concern, and vessel strikes are a leading cause of serious injury and mortality for baleen whales. Yet vessel strikes have rarely been studied in the Arctic. Vessel traffic is increasing throughout the Arctic as sea ice is declining, leading to increased overlap between vessels and whales. We examined hypothetical vessel strike risk for the Bering-Chukchi-Beaufort (BCB) and Eastern Canada-West Greenland (ECWG) populations of bowhead whales during the open-water shipping season. We used satellite telemetry and aerial survey data to calculate monthly relative density of both populations, and satellite vessel tracking data to calculate monthly vessel density and speed. We estimated vessel strike risk by multiplying whale density by vessel density corrected by vessel speed. For the BCB population, the highest relative risk was near Utqiaġvik and Prudhoe Bay, Alaska, USA, and near Tuktoyaktuk, Northwest Territories, Canada. For the ECWG population, the highest risk was in the Gulf of Boothia, Cumberland Sound, and near Isabella Bay, Nunavut, Canada. Strike risk was highest in August and September, corresponding with monthly trends in vessel traffic. This study provides important information for focussed monitoring and to minimize/mitigate the threat of vessel strikes to bowhead whales. Although vessel strike risk is presently lower for these populations than for other temperate large cetacean populations, bowhead whale behaviour and projected increases in traffic elevates their risk in the Arctic. Measures to mitigate vessel strike risk to bowhead whales will likely benefit other Arctic marine mammals like beluga and narwhal.
... Such approaches can be used to identify and project interactions between distributions of species and anthropogenic pressures, including climate change (Vanderwal et al., 2013;Silber et al., 2017), human presence (Nickel et al., 2020;Suraci et al., 2021), recreational tourism activities Larson et al., 2016), and importantly, estimates of cumulative human impact (Halpern et al., 2015). In the marine environment, intersections between species distributions and fisheries impacts (Slooten, Rayment & Dawson, 2006;Read, 2008), offshore energy development (Thompson et al., 2010), commercial shipping (Redfern et al., 2013;Constantine et al., 2015), plastic pollution (Di-Méglio & Campana, 2017) and seismic exploration (Kavanagh et al., 2019) are of immediate concern. ...
Before the 2020 COVID‐19 pandemic, cruise ship tourism had been one of the fastest growing segments of global tourism, presenting a range of potential impacts. At Akaroa Harbour, Aotearoa New Zealand, the number of annual cruise ship visits more than quadrupled following earthquake damage to Ōtautahi Christchurch's Lyttelton Port in 2011. Akaroa Harbour is an area of core use for endangered and endemic Hector’s dolphins (Cephalorhynchus hectori). Dolphins here are exposed to some of the highest levels of cetacean tourism in Aotearoa New Zealand. Relationships were examined between growth in cruise ship visits, as well as tours focused specifically on dolphins, and long‐term trends in summer distribution of Hector’s dolphins at Akaroa Harbour, from 2000 to 2020. Core use areas for Hector’s dolphins within the harbour were quantified via kernel density estimation using data from 2,335 sightings from over 8,000 km of standardized survey effort. Data were allocated into four periods based on varying levels of tourism. Dolphin habitat preference varied over time, with the greatest change occurring between 2005–2011 and 2012–2015. When comparing these periods, the spatial overlap of core habitat was less than 24%. Dolphin distribution shifted towards the outer harbour after 2011 and has remained relatively consistent since. The observed shift in distribution coincided with the more than fourfold increase in annual cruise ship visits to Akaroa Harbour. Several pressures related to cruise ship tourism are likely to have influenced habitat preferences of dolphins. Further investigation into causal factors of the observed shift is warranted. In the wake of the COVID‐19 pandemic, the future of cruise ship and wildlife tourism is in flux. Our findings suggest that the future re‐development of this industry should follow a precautionary approach, with the onus on industry to provide evidence of sustainability before proceeding.
... Recently, sightings of Bryde's whale have been recorded from the coasts of East and Southeast Asia (Yamada et al., 2008;Chen et al., 2019;Liu et al., 2021), south west Indian Ocean , Southern Africa (Best, 2001;Penry et al., 2011) and Gulf of Mexico (Rosel and Wilcox, 2014). However, as the type specimen for B. e. brydei was not designated with the naming of the species, and genetic analysis of the type specimen of B. e. edeni was not completed, detailed taxonomy within the Bryde's whale group is unclear (Anderson, 1879;Constantine et al., 2015). ...
DNA barcoding technology is becoming an increasingly powerful tool in resolving issues of detailed species identification based on morphology, as commonly employed by museums. In the present study, we aimed to identify a stranded Bryde’s whale on Hainan Island, China by extracting DNA from a vertebra pre-treated by physical and/or chemical processes. Based on morphological characteristics, this Bryde’s whale was initially determined as Balaenoptera edeni. Then, DNA was efficiently extracted using ancient DNA techniques. The mitochondrial gene (COI) phylogenetic analysis further revealed that this museum whale specimen belonged to the sub-species B. e. edeni. This study provides a testable and rapid method for museum species verification, by using ancient DNA extraction methods to compensate the disadvantage of traditional DNA extraction methods that are difficult to extract valid DNA.
... The option they agreed to undertake was voluntary speed restrictions together with a monitoring plan. Through the continuing involvement of stakeholders and scientists, this has proved to be effective, highlighting the value of a stakeholder-led process that includes monitoring (Constantine et al. 2015). ...
Protecting habitat, or pieces of open ocean, for highly mobile marine mammal species that traverse ocean basins presents one of the greatest challenges in marine conservation. Among the tools available for identifying, monitoring, and maintaining defined spaces are a wide variety of marine protected areas (MPAs), IUCN important marine mammal areas (IMMAs), IUCN key biodiversity areas (KBAs), Convention on Biological Diversity (CBD) ecologically or biologically significant areas (EBSAs), Ramsar Convention on Wetlands sites, the migratory connectivity in the ocean (MiCO) system, and marine spatial planning (MSP) including through comprehensive ocean zoning. There are also spatial and regulatory strategies available such as through the International Maritime Organisation (IMO) to re-route shipping and to declare particularly sensitive sea areas (PSSAs) or areas to be avoided (ATBAs). Using these spatial tools singly in some cases or in combination, often with clever modifications or incorporating directives such as initiatives to modify fishing gear, can form a strategy toward implementing successful marine mammal conservation with substantial benefit to associated biodiversity conservation. MPAs, for example, can be zoned for various uses with high levels of core habitat protection as needed. MPAs designed according to biosphere reserve principles can have large buffer zones and dynamic core protection. Also, MPAs sometimes referred to as marine mammal protected areas, or MMPAs, when their remit is partly focused on marine mammal populations—can function as part of networks to protect wide-ranging species or migrators at both ends of their migratory path. The effectiveness of MPAs, MSP, and other initiatives depends on the political will to translate conservation science into action by supplying budgets, legislation, and
enforcement to address threats to marine mammals, as well as stimulating education and engagement of the public and all stakeholders —everyone who uses, enjoys, cares about the sea. The evolving human factor is the biggest unknown, yet potentially the most important, for determining the success or failure of efforts to conserve marine mammal habitats. It is fundamental to realize that spatial management tools, to be successful, must focus primarily on shaping and managing human behavior. Will the public, energy companies, manufacturers, builders and government recognize that ocean conservation is an integral part of the drive to reduce global warming and address the species extinction crisis? It is up to those of us alive today to determine
the fundamental nature of the world that species, including our own species, will inhabit in future.
Keywords: Habitat · Marine mammal · Marine conservation · Protected area · Marine spatial planning · Important marine mammal area · Spatial management · Ecologically or biologically significant area
Erich Hoyt, Whale and Dolphin Conservation, Park House, Allington Park, Bridport, Dorset DT6 5DD, England, UK e-mail: erich.hoyt@imma-network.org, and IUCN SSC-WCPA Marine Mammal Protected Areas Task Force, Gland, Switzerland
© Erich Hoyt 2022, under exclusive license to Springer Nature Switzerland AG 2022
Citation: Hoyt, E. 2022. Conserving Marine Mammal Spaces and Habitats. In G. Notarbartolo di Sciara and B. Würsig (eds.) Marine Mammals: The Evolving Human Factor. Series Ethology and Behavioral Ecology of Marine Mammals, B. Würsig (ed.), Springer, Cham, Switzerland. pp31-82
ISSN 2523-7500, ISSN 2523-7519 (electronic); ISBN 978-3-030-98099-3, ISBN 978-3-030-98100-6 (eBook);
https://doi.org/10.1007/978-3-030-98100-6
... In addition to Whale Alert (Wiley et al., 2013), the National Oceanic and Atmospheric Administration (NOAA) can implement Dynamic Management Areas (DMAs) and Right Whale Slow Zones (NOAA, 2021c), which use near real-time visual (DMA) or visual and acoustic (Right Whale Slow Zones) detections to establish areas where mariners are encouraged to reduce vessel speed or to avoid. However, compliance in both programs is voluntary and previous work has shown voluntary rules, including DMAs, to be largely ineffective (Lagueux et al., 2011;McKenna et al., 2012;Silber et al., 2012), though Canada and New Zealand had some success with voluntary ship strike reduction measures (Vanderlaan and Taggart, 2009;Constantine et al., 2015;Ebdon et al., 2020). Mandatory, dynamic strategies may better reduce vessel strike risk to whales (Hausner et al., 2021). ...
Vessel strike and entanglement in fishing gear are global threats to large whales. United States management actions to reduce human-induced serious injury and mortality to large whales have been inadequate, partially due to static, spatial protection schemes that fail to adjust to distribution shifts of highly mobile animals. Whale conservation would benefit from dynamic ocean management, but few tools exist to inform dynamic approaches. Seabirds are often found in association with whales and can be tagged at lower cost and in higher numbers than whales. We explored the use of satellite-tagged seabirds (great shearwaters) as dynamic ocean management tools for near real-time identification of habitats where humpback and North Atlantic right whales aggregate, potentially increasing anthropogenic risk. We identified shearwater habitat use areas in the Gulf of Maine with 50% kernel density utilization distributions at yearly, monthly, and weekly scales using satellite-telemetry data from 2013-2018. We quantified overlap using whale sightings and whale satellite telemetry data at two spatial scales: Stellwagen Bank National Marine Sanctuary and the Gulf of Maine. Within the sanctuary, shearwaters overlapped with >50% of humpback sightings in 4 of 6 (67%) years, 15 of 23 (65%) months, and 50 of 89 (56%) of weeks. At the Gulf of Maine scale, shearwater use areas overlapped >50% of humpback sightings in 5 of 6 years (83%) and 16 of 22 (73%) months, and encompassed humpback 50% utilization distributions (based on satellite telemetry) in 2 of 3 (66%) years and 7/12 (58%) months analyzed. Overlap between shearwaters and right whales was much lower, with >50% overlap in only 1 of 6 (17%) years and 3 of 23 (13%) months. These initial results demonstrate that satellite-tagged shearwaters can be indicators of humpback whale habitat use in both space and time. With further study, tagged shearwaters may provide near-real time information necessary to operationalize dynamic management to mitigate human impacts on humpback whales.
... Two whales did not have distinctive marks and one was not photographed and therefore are not in the catalog. Animals were approached from a 6 m rigid-hulled inflatable boat and tagged by means of a 6 m long hand-held pole (Constantine et al., 2015). The tags were attached to the whales with suction cups and were programmed to release after a maximum of 24 hr, but all released earlier (Table 1). ...
Large predators typically feed on proportionally sized prey but the world's largest animals, baleen whales, bulk feed on plankton and small fishes. While most baleen whales migrate to feed on polar aggregations of nutritious zooplankton prey, Bryde's whales (Balaenoptera edeni brydei and B. e. edeni) inhabit less productive warm‐temperate waters with variable prey abundance and quality. Off New Zealand, Bryde's whales target both fish and zooplankton, some with lower calorific value. We use multisensor tags (n = 4) and visual observations from drones and boats (n = 52) to reveal that Bryde's whales employ specialized feeding tactics matched to prey type. Zooplankton‐feeding at the surface involved multiple head‐slaps that presumably aggregate zooplankton followed by a side‐lunge. Whales exploiting plankton patches swam in tight circles, performing up to 33 lunges (M = 5.5 ± 6.1) per feeding bout. In contrast, whales targeting fish performed faster vertical lunges. With both prey types, whales concluded lunges with a ~90° roll probably to minimize prey escape at the surface. The diet plasticity and dynamic behaviors of Bryde's whales are key to increasing their foraging efficiency. This may be essential for the whales to meet energetic demands year‐round with a variety of prey in New Zealand waters.
... Instead, permanent or seasonal speed restriction zones over the whole at-risk region, based on the north-western IMMA, the upcoming ship strike new Cetacean Critical Habitat and the high-risk exposure maps from this study and others, could be the better choice (IWC-IUCN-ACCOBAMS, 2019). It is clear that reducing vessel speeds to below 13 knots could be a good option to reduce NME rates, distance of sighting and lethal strikes (Vanderlaan & Taggart, 2007;Silber, Slutsky & Bettridge, 2010;Laist, Knowlton & Pendleton, 2014;Constantine et al., 2015;Van der Hoop et al., 2015). ...
The Mediterranean Sea is a high‐density maritime traffic area, particularly in the Pelagos Sanctuary. Ship strikes pose a substantial threat to fin whales (Balaenoptera physalus) according to reports from the IUCN, the IWC, the ACCOBAMS and the EU Habitats Directive. Near miss events (NMEs) were collected, as a proxy indicator of ship strikes for fin whales, along the main ferry routes crossing the Pelagos Sanctuary and adjacent western waters during ‘summertime’ (April to October). The ‘Fixed Line Transect Med Network’ carries out systematic surveys from ferries and collects data according to the ‘linear transect’ method. From 2008 to 2019, 13 different ferry routes were surveyed with 238,499 km monitored. Of the 2,775 fin whales encountered, 43 individuals were involved in NMEs (1.55% of the sightings). NMEs occur over the great majority of the routes monitored with enough effort and were correlated with the density index of fin whales. High‐risk areas for NMEs were identified in the central and deeper parts of the north‐western Mediterranean Sea and in some sections of the northern Tyrrhenian Sea. Of all NMEs, the majority of whales (63.4%) surfaced in front of the vessel (<50 m), leaving no time for the crew to manoeuvre the vessel. The others were travelling (26.8%) or resting (9.7%) without any noticeable reaction at the vessel. The speed of the ferries seems to play a role in the occurrence of the NME, as this parameter is significantly different (t‐test, P = 0.002) for NMEs compared to all fin whale sightings, whereas month and hour of day were not. Quantifying NMEs based on real‐time observation with observers on board, could be used as a feasible and efficient way to limit collisions, raising awareness by the crew, and testing or evaluating other potential tools that can help mitigate this threat.
... Also, by being a migratory species, they are expected to leave the area, and with individuals being resighted in the following years, this reinforces the ecological explanation of emigration for this analysis. Notwithstanding, anthropogenic causes of mortality pose a threat for many species of large whales (e.g.Constantine et al., 2015;Fais et al., 2016;Dolman & Brakes, 2018;Fossi et al., 2018), and cannot be disregarded.The connectivity found in this study between neighbouring oceanic archipelagos in Macaronesia for Bryde's whales was expected, taking into consideration the biogeographical similarities between the Madeira Archipelago and the Canaries(Freitas et al., 2019), and the migration behaviour of Bryde's whales within oceanic basins(Kato & Perrin, 2018). These movements are also in accordance with what is observed for other species in the same area (e.g.Steiner et al., 2015;Alves et al., 2019;Dinis et al., 2021). ...
• The conservation of marine megafauna presents numerous difficulties owing to their high mobility over difficult-to-access oceanic areas that impairs the collection of basic, but essential, biological information.
• The Bryde's whale (Balaenoptera edeni) is one of the most elusive species of baleen whales, and although it is known to be a seasonal visitor to several archipelagos in Macaronesia (the Azores, Madeira, and Canaries), there are no studies regarding its occurrence or geographical connectivity in this area of the Atlantic.
• A 14-year photographic database was used to determine short-term (intra-seasonal) and long-term (inter-annual) Bryde's whale site fidelity and to estimate individual residency times in Madeira, whereas photographic catalogues from Madeira and the Canaries were compared in order to assess large-scale movements (i.e. on the scale of hundreds of kilometres).
• In Madeira, 59 individuals were identified, 27 (45.8%) of which were recaptured. Of these, 10 individuals (37.0%) presented short-term site fidelity and 17 individuals (63.0%) presented long-term site fidelity, with a maximum recapture interval of 12 years. Lagged identification rates showed that five individuals (SE = 2) remained in the area for 32 days (SE = 108 days) before leaving and not returning during the same year. Seven individuals were seen both in Madeira and the Canaries (catalogue comprising 51 individuals), three of which were identified multiple times in both archipelagos, with a minimum of 43 days between consecutive sightings.
• This information combined with the fact that this species is commonly sighted accompanied by calves and feeding in both archipelagos highlights the ecological importance of this area for Bryde's whales. This should be taken into consideration by policymakers when implementing conservation measures, where coordination of effort among countries is needed. This study also reinforces the value of using data from platforms of opportunity and of making photographic data open access.
... e. brydei [11,12]. The Bryde's whale was globally classified as "Least Concern" by the Red List of Threatened Species, International Union for Conservation of Nature [13], but a few geographical populations were regionally assessed "Endangered" or "Critically Endangered" [14,15]. Nevertheless, there are numerous datadeficient areas with scant field investigation on this species [16]. ...
Abstract: Satellite-tagging is increasingly becoming a powerful biotelemetry approach to obtain remote measurement through tracking free-living cetaceans, which can fill knowledge gaps on cetaceans and facilitate conservation management. Here, we made a first biologging attempt on baleen whales in Chinese waters. An adult Bryde’s whale in the Beibu Gulf was tagged to investigate potential occurrence areas and migration routes of this poorly studied species. The whale was satellite-tracked for ~6 days with 71 filtered Argos satellite locations, resulting in a linear movement distance of 464 km. At each satellite-tracking location, the water depth was measured as 42.1 ± 24.8 m on average. During the satellite-tracking period, the whale’s moving speed was estimated at 5.33 ± 4.01 km/h. These findings expanded the known distribution areas of Bryde’s whales in the Beibu Gulf and provided an important scientific basis for the regional protection of this species. We suggest that fine-scale movements, habitat use, and migratory behavior of Bryde’s whales in the Beibu Gulf need more biotelemetry research, using long-term satellite-tracking tags and involving enough individuals. Furthermore, the genetic relationship and possible connectivity of Bryde’s whales in the Beibu Gulf and adjacent waters should be examined.
... This includes involving a motivational element in education, creating a message that focuses on specific, achievable actions, and promoting positive behavior changes rather than discouraging certain actions (Schultz, 2011). To encourage community involvement and support of behavior changes, educational outreach needs to be designed with the local community and environment in mind (Constantine et al., 2015;Flamm & Braunsberger, 2014;Gubbay, 1993). Additionally, buy-in and participation from all stakeholders is beneficial (Perry & Perry, 2008). ...
Ecotour compliance to viewing guidelines should be evaluated holistically, considering actual and perceived compliance levels, as well as boat captain and passenger knowledge of the guidelines. This multi-faceted approach was used to assess ecotour compliance levels to the NOAA marine mammal viewing guidelines while interacting with bottlenose dolphins (Tursiops truncatus) in Southwest Florida. Ecotour compliance was assessed via observations of boat-based dolphin ecotours in 2019. Captain and passenger knowledge and opinions of the guidelines were obtained through questionnaires, as well as captains’ perceived compliance and how compliance affected passenger experience. Ecotour captains violated an average of 44% of the guidelines. Captains generally knew and supported the guidelines, as well as knew when they were being noncompliant, with 75% demonstrating equally perceived and observed compliance levels. This may reflect a lack of understanding of the cumulative effects of noncompliance on dolphins. Passengers supported the guidelines and valued compliance but did not have enough knowledge about the guidelines to recognize captain violations. Most passengers were willing to pay more for compliant tours, and 84% reported that guideline violations would negatively affect their trip. Our findings can inform management and outreach initiatives in the region to increase compliance.
... S7), in line with trends observed elsewhere, e.g., Northern Adriatic Sea, Italy . Some experiences have proved the manageable nature of this pressure by means, for instance, of traffic control schemes (e.g., Agardy et al., 2019) or controlled speed reduction (e.g., Constantine et al., 2015). ...
Despite the recognized important ecological role that cetaceans play in the marine environment, their protection is still scarcely enforced in the Mediterranean Sea even though this area is strongly threatened by local human pressures and climate change. The piecemeal of knowledge related to cetaceans' ecology and distribution in the basin undermines the capacity of addressing cetaceans' protection and identifying effective conservation strategies. In this study, an Ecosystem-Based Marine Spatial Planning (EB-MSP) approach is applied to assess human pressures on cetaceans and guide the designation of a conservation area in the Gulf of Taranto, Northern Ionian Sea (Central-eastern Mediterranean Sea). The Gulf of Taranto hosts different cetacean species that accomplish important phases of their life in the area. Despite this fact, the gulf does not fall within any area-based management tools (ABMTs) for cetacean conservation. We pin down the Gulf of Taranto being eligible for the designation of diverse ABMTs for conservation, both legally and non-legally binding. Through a risk-based approach, this study explores the cause-effect relationships that link any human activities and pressures exerted in the study area to potential effects on cetaceans, by identifying major drivers of potential impacts. These were found to be underwater noise, marine litter, ship collision, and competition and disturbance on preys. We draw some recommendations based on different sources of available knowledge produced so far in the area (i.e., empirical evidence, scientific and grey literature, and expert judgement) to boost cetaceans' conservation. Finally, we stress the need of sectoral coordination for the management of human activities by applying an EB-MSP approach and valuing the establishment of an ABMT in the Gulf of Taranto.
... [39]); therefore, the potential for ship strike in the narrow channel is possible. Ship strike is a global threat to large whales [86][87][88], and sound resonation in the Strait could make it difficult for whales to localize and consequently avoid ship traffic. In the Northern Hemisphere, North Atlantic right whales (Eubalaena glacialis) are particularly vulnerable to ship strike as they do not exhibit behavioural responses to ship sound [89]. ...
Baleen whales reliably produce stereotyped vocalizations, enabling their spatio-temporal distributions to be inferred from acoustic detections. Soundscape analysis provides an integrated approach whereby vocal species, such as baleen whales, are sampled holistically with other acoustic contributors to their environment. Acoustic elements that occur concurrently in space, time and/or frequency can indicate overlaps between free-ranging species and potential stressors. Such information can inform risk assessment framework models. Here, we demonstrate the utility of soundscape monitoring in central New Zealand, an area of high cetacean diversity where potential threats are poorly understood. Pygmy blue whale calls were abundant in the South Taranaki Bight (STB) throughout recording periods and were also detected near Kaikoūra during autumn. Humpback, Antarctic blue and Antarctic minke whales were detected in winter and spring, during migration. Wind, rain, tidal and wave activity increased ambient sound levels in both deep-and shallow-water environments across a broad range of frequencies, including those used by baleen whales, and sound from shipping, seismic surveys and earthquakes overlapped in time, space and frequency with whale calls. The results highlight the feasibility of soundscape analysis to quantify and understand potential stressors to free-ranging species, which is essential for conservation and management decisions.
... Les grands cétacés tels que la baleine à bosse (Megaptera novaeangliae) sont plus sensibles aux collisions dans les zones où les grands axes maritimes chevauchent leur habitat (Currie et al., 2017). Ce risque est accru lorsque les baleines se reposent ou se déplacent lentement à la surface (Constantine et al., 2015;Laist et al., 2001;Vanderlaan et Taggart, 2007). Les études récentes confirment que 11 espèces sont concernées à travers le monde (Jensen & Silber, 2003 ;Van Waerebee et al., 2007). ...
Report on collision risk between Humpback whale (Megaptera novaeangliae) and ferries between Tahiti and Mooera Islands, NGO Oceania, French Polynesia.
... Bryde's whales hold the highest conservation threat status in New Zealand (threatenednationally critical). Between 1996 and 2014, 44 Bryde's whales have been reported dead in New Zealand, with at least 17 of these likely being the result of ship strike(Constantine et al. 2015), a known occurrence particularly in areas with high levels of boat traffic such as the Hauraki Gulf. Most incidents and strandings have occurred in the Hauraki Gulf and occasionally in other locations along the North Island coastline. ...
The distribution of marine mammal species in many areas remains poorly understood, especially as observations for some taxa are rare and large-scale surveys are time consuming and extremely costly. Here, we present 36 records of 7 cetacean species (Balaenoptera brydei, B. musculus subspp., Delphinus delphis, Globicephala sp., Grampus griseus, Physeter macrocephalus, Pseudorca crassidens) in the New Caledonia Basin, Tasman Sea, along with their associated biological and environmental data. Data were derived from a platform of opportunity during a seismic survey that ran between December 2015 and March 2016, inclusively. The two most frequently encountered species were sperm whales (Physeter macrocephalus, 13 sightings, 5 acoustic detections) and blue whales (Balaenoptera musculus subspp., 8 visual detections). All encountered species are known to occur in New Zealand waters at least occasionally, based on historical sightings and stranding records. However, data presented here are the first cetacean records for this specific area and demonstrate that seismic vessels can act as a platform of opportunity for studying cetacean distribution in poorly accessible areas. Such data will aid future research efforts including species distribution models on cetaceans in the South Pacific.
... Between 1995 and 2000, six whales had, or were likely to have been killed by ship strike in the Marine Park. 138 Small fish such as pilchards and saury were the primary food for Bryde's whales. 139 ...
State of the Environment Report for the Hauraki Gulf
... The B. e. edeni is the small, coastal form of the B. edeni while B. e. brydei refers to the large, offshore form [6]- [9]. Several studies have been recently carried out on the existence of Bryde's whales from different geographic location, such as the Gulf of Mexico [9]- [11], Gulf of California [12], [13], Hauraki Gulf, New Zealand [3], [14], [15], Eastern Tropical Pacific [6], [16], and Southern Brazil [17]- [20]. While some of these literatures have described the population, spatial distribution, genetic and phylogenetic features, attributed nomenclature, a few have described the potential vocal repertoire of this marine species. ...
Marine mammals use sound for communication and echolocation within their ecosystems. The detection of these sounds is an important aspect of signal processing, such that we can estimate the spatial position and direction of arrival of these mammals, and have an understanding of their ecology. Passive acoustic monitoring (PAM) is widely used to understand marine mammal movement and vocal repertoire. In PAM, datasets are accumulated over days, months or years. Thus, it is impracticable to manually analyse the datasets because it is very large. This motivated the development of automated sound detection techniques for marine mammals, which most often varies depending on the vocal duration, frequency range and call type. In this paper, continuous recordings of Bryde’s whale (Balaenoptera edeni edeni) short pulse calls (< 3.1s long) were collected on a weekly basis from December 2018 to April 2019 on sighting of the individual in a single site in the endmost South-West of South Africa. The sound, previously not documented off South Africa, was observed on visual confirmation of the presence of inshore Brydes’s whale. In addition, the paper develops and analyses two automated template-based detection algorithms for this short pulse call, employing dynamic time warping (DTW) and linear predictive coding (LPC) techniques. These proposed template-based detectors are novel, as they have not being previously used in Bryde’s whale sound detection in the literature. When applied to the continuous recordings of the short pulse calls, the DTW-based and LPC-based detection algorithms obtained a sensitivity of 96.04% and 97.14% respectively for high signal-to-noise ratio (about 10dB above the ambient sound). Otherwise, for low SNR, the DTW-based and LPC-based detection algorithms obtained a sensitivity of 94.98% and 96.00% respectively. These detection algorithms exhibit low computational time complexity and can be modified to analyse the movement of obscure but vocal marine species instead of manual identification.
... This layer defines human density centers as provincial capital cities, major population centers, landmark cities, national capitals, and shipping ports. These two distance metrics are derived to indirectly capture the many cumulative effects which humans have on ecosystem predators [32,72] including noise pollution [73], nonreported fishing [1], vessel strikes [74], infrastructure development [72], and direct exploitation [75]. Moreover, these metrics encompass some aspects of the historical impacts that have occurred before the onset of modern record keeping [1,76]. ...
Since the 1950s, industrial fisheries have expanded globally, as fishing vessels are required to travel further afield for fishing opportunities. Technological advancements and fishery subsidies have granted ever-increasing access to populations of sharks, tunas, billfishes, and other predators. Wilderness refuges, defined here as areas beyond the detectable range of human influence, are therefore increasingly rare. In order to achieve marine resources sustainability, large no-take marine protected areas (MPAs) with pelagic components are being implemented. However, such conservation efforts require knowledge of the critical habitats for predators, both across shallow reefs and the deeper ocean. Here, we fill this gap in knowledge across the Indo-Pacific by using 1,041 midwater baited videos to survey sharks and other pelagic predators such as rainbow runner (Elagatis bipinnulata), mahi-mahi (Coryphaena hippurus), and black marlin (Istiompax indica). We modeled three key predator community attributes: vertebrate species richness, mean maximum body size, and shark abundance as a function of geomorphology, environmental conditions, and human pressures. All attributes were primarily driven by geomorphology (35%-62% variance explained) and environmental conditions (14%-49%). While human pressures had no influence on species richness, both body size and shark abundance responded strongly to distance to human markets (12%-20%). Refuges were identified at more than 1,250 km from human markets for body size and for shark abundance. These refuges were identified as remote and shallow seabed features, such as seamounts, submerged banks, and reefs. Worryingly, hotpots of large individuals and of shark abundance are presently under-represented within no-take MPAs that aim to effectively protect marine predators, such as the British Indian Ocean Territory. Population recovery of predators is unlikely to occur without strategic placement and effective enforcement of large no-take MPAs in both coastal and remote locations.
... A year-round population of Bryde's whales inhabits the entrance of the Hauraki Gulf to the Port of Auckland, New Zealand. Since 1996, 85% of all 44 documented Bryde's whale deaths (2.3/per year) have been attributed to ship strikes (Constantine et al. 2015). The local population of Bryde's whales in the Hauraki Gulf is estimated at 159 whales. ...
The International Whaling Commission (IWC) has identified the need to produce a Strategic Plan describing its activities intended to reduce the threat of ship strikes with cetaceans in the near and distant future. This document provides the necessary background, information and recommendations to help the IWC develop approaches and solutions by 2020 to achieve a permanent reduction in ship strikes of cetaceans.
... 12,24 ) resulting in a temporal and spatial overlap between whales and vessels. In turn, this has resulted in an apparent increase in vessel strikes of whales [25][26][27][28][29] . Accordingly, vessel strikes are one of the major conservation concerns to whale populations globally. ...
Understanding the behaviour of humpback whale mother-calf pairs and the acoustic environment on their breeding grounds is fundamental to assessing the biological and ecological requirements needed to ensure a successful migration and survival of calves. Therefore, on a breeding/resting ground, Exmouth Gulf, Western Australia, we used animal-borne DTAGs to quantify the fine-scale behaviour and energetic expenditure of humpback whale mothers and calves, while sound recorders measured the acoustic environment. We show that: (i) lactating humpback whales keep their energy expenditure low by devoting a significant amount of time to rest, and their use of energy, inferred from respiration rates, is ~half than that of adults on their foraging grounds; (ii) lactating females mainly rest while stationary at shallow depths within reach of the hull of commercial ships, thus increasing the potential for ship strike collisions; (iii) the soundscape is dominated by biological sources; and (iv) even moderate increases of noise from vessels will decrease the communication range of humpback whales. Planned commercial infrastructure in Exmouth Gulf will cause a substantial increase in shipping traffic with the risk of ship strikes and acoustic disturbance potentially compromising energy reserves for the southern migration of humpback whales.
... In particular, shipping risks including collisions with whales [1] and impacts of underwater noise [2] are social-ecological issues that have triggered mitigation endeavors all around the world [3][4][5]. Focusing on the acknowledged issue of collisions between merchant ships and large whales [6], the perspective of an increase in commercial shipping [7,8] is calling for effective mitigation measures to reduce collision risks, especially for endangered cetacean species [9,10]. ...
Lethal collisions with ships are limiting the recovery of several at-risk whale species worldwide. In the St. Lawrence Estuary (Quebec, Canada), the endangered blue whale and of special concern fin whale are among the migratory species subject to collisions with large ships. In 2011, a working group composed of representatives from the maritime industry, the government, non-governmental organizations, and academia was created to explore solutions to mitigate ship-whale collisions in the St. Lawrence Estuary. Adopting an adaptive risk management framework, the working group took advantage of the best available scientific data and tools to co-construct realistic collision mitigation options and evaluate their likely benefits for whale conservation and costs for the industry. In 2013, the working group recommended the implementation of voluntary measures to mitigate collision risks, consisting of a slow-down area, a no-go area, and a caution area; a recommended route was added in 2014. Along with the voluntary framework, the working group agreed to continuously monitor compliance with and assess effectiveness of these mitigation measures. After the fourth year of implementation, voluntary measures showed encouraging results, with a reduction of up to 40% of lethal collision risks with fin whales in the highest density area. This reduction in risk is mainly related to ship speed reduction in the slow-down area from 14.1 ± 2.6 knots in 2012 to 11.3 ± 1.7 knots since 2014. The presence of a mandatory pilotage area overlapping with the slow-down area was instrumental to facilitate communication about the mitigation measures, with the pilotage corporation sitting as a regular member of the working group. This resulted in significantly slower speeds in the slow-down area for ships with a pilot from the pilotage corporation onboard compared to those without (-0.8 knots, p-value < 0.001). It is also likely to explain the weaker compliance of the maritime industry with the no-go area located outside of the mandatory pilotage area. Other factors of success include: the continuous dedication of the government to a voluntary and transparent participatory process; the use of available data, tools and institutions; the presence of an environmental certification program representative in the working group; and the adoption by consensus of an adaptive risk management approach. The traditional regulatory approach to conservation is often blamed for its focus on deterring negative behaviors, doing nothing to encourage and reward positive ones. In agreement with other case studies, the benefits of the voluntary measures implemented in the St. Lawrence Estuary include the pro-active commitment from the industry (which is likely to reduce conflicts with regulators), the greater flexibility and freedom that allowed to come up with cost-effective and tailored-made mitigation measures, and the fast achievement of conservation gains. More importantly perhaps, the human and working capital built throughout the concertation process have the potential to be a fundamental cornerstone in dealing with more complex issues such as the chronically increasing level of underwater noise in whale habitats.
... Naval midfrequency sonar is criticized for its potentially negative effect on marine mammals and has been implicated in several whale stranding events. To minimize possible adverse impacts on individuals and their populations (e.g., D'Amico et al. 2009;Miller et al. 2012), competent authorities commonly require the implementation of mitigation measures, including vessel speed reductions and shutdown of acoustic sources, if marine mammals are sighted in high-risk areas or in a predefined exclusion zone around the vessel (Weir and Dolman 2007;Laist et al. 2014;Constantine et al. 2015). ...
Vessel collisions are an important threat to several cetacean species, both large and small. In addition to negatively affecting the animals themselves, collisions can also damage or sink vessels, threatening both human safety and marine industry economics. Larger cetaceans seem to be the most affected by vessel collisions, and vessel strikes with Bryde's whales (Balaenoptera brydei/Balaenoptera edeni) have been reported worldwide. Long‐term photo‐identification research on Bryde's whales off the northern coast of the state of São Paulo, Brazil, has been continuing since 2016. Of the 67 individuals that were photo‐identified between 2004 and January 2022, three (4%) presented scars compatible with injuries from vessel propellers. These data contribute towards an understanding of the long‐term effects of collision injuries on the behaviour and survival of Bryde's whales. This report is intended to help inform the future evaluation of the conservation status of B. brydei off Brazil.
The rapid recovery of the Australian humpback whale (Megaptera novaeangliae) population and parallel increase in maritime traffic, has increased the spatial overlap between whales and vessels in Australian waters. Ship strike is a recognized global anthropogenic source of mortality or injury to large whales, and a potentially increasing risk in Australia. However, our understanding and evaluation of this threat to humpback whales around Australia, is hindered by the lack of seasonal whale distribution data in high marine traffic areas. Here, we present five consecutive years (2017–2021) of both north and south migrating humpback whale distribution data to quantify the relative risk of ship strike based on the co-occurrence with commercial ships in Moreton Bay. This marine embayment is home to Australia’s fastest growing container port (The Port of Brisbane) and has recently been identified for its ecological importance to this migrating species. We quantified co-occurrence by multiplying predicted whale and ship densities together to estimate both intra- and inter-annual ship strike risk. Ship strike risk increased during the humpback whale’s southern migration (September-October), coinciding with a substantial habitat shift into the Bay during this time. Groups containing calves were a predominant pod type in Moreton Bay. Given their increased vulnerability to ship strike, this study underscores the need for immediate and effective mitigation actions, such as seasonal vessel speed reductions as well as mariner education and outreach programs.
Small recreational boats are an omnipresent source of sound pollution in shallow coastal habitats, which can impact the behavior and physiology of a wide array of taxa. However, effective monitoring of this stressor is currently limited by a lack of tools. The present study coupled passive acoustic monitoring (PAM) with timelapse imagery to provide a comprehensive analysis of sound pollution at two coastal sites varying in habitat structure: Goat (rocky reef) and Kawau (sandy bay) Islands. A convolutional neural network (CNN) was used to automatically count boats in each image, and the relationship between the soundscape and number of boats present was analysed using power spectral density and adaptive threshold analyses. Small boat activity was positively correlated with third octave level (TOL) root mean squared sound pressure levels (SPLRMS 63 – 5011 Hz), and this effect was frequency dependent, at both Goat (F7,9704 = 5.665, p < 0.001) and Kawau (F7,42488 = 325.33, p < 0.001) Islands. However, at Goat Island this interaction effect was driven by a significant difference between 63 Hz and all other TOLs (p < 0.05), whereas at Kawau Island the interaction effect of TOL and boat number was more variable. Furthermore, low frequency (∼50 – 300 Hz) biophony was found to influence the likelihood of boat sound being detected at Goat Island. Small boat impacts are contextual, likely due to habitat specific propagation conditions and the presence/absence of vocalising animals. As such, monitoring of sound pollution in coastal habitats requires a tailored approach which accounts for the localised nature of shallow coastal soundscapes. These findings demonstrate the potential for timelapse imagery to elucidate variability in boat sound, which may be particularly useful for remote sites which are ecologically rich, yet have no acoustic protections, such as many marine protected areas.
Marine mammal strandings provide vital information on species’ life histories, population health and status of marine ecosystems. Opportunistic reporting of strandings also serve as a powerful low-cost tool for monitoring these elusive mammals. We collated data over ~ 270 years available through various open access databases, reports and publications. Annual strandings along the Indian coast (mean = 11.25 ± SE 9.1) increased in the last two years of the study (2015–2017, mean = 27.66 ± SE 8.5 strandings /year). We found that stranding events spike during June—September along the west coast and during December–January along the east coast. We identified several sections of the coastline, such as Mumbai (0.38 strandings/km), Kozhikode (0.28 strandings/km), Tuticorin (0.4 strandings/km), Rameswaram (1.82 strandings/km), Chennai (0.32 strandings/km) and Bhubaneshwar (0.26 strandings/km) with a higher number of stranded animals reported. Emerging Hotspot Analysis located new and consecutive hotspots along the north-west coast, and sporadic hotspots along the south-east coast. We recommend establishing regional stranding response centres at the identified hotspots coordinated by a National Stranding Centre with adequately trained personnel and central funding support. Regular stranding response training programs for field veterinarians, and frontline personnel of State Forest Departments near stranding hotspots would provide an improved understanding of marine mammal health and threats in Indian waters. Further, the suggested National Stranding Centre needs to maintain a ‘National Stranding Database’ for long-term marine mammal conservation planning in India.
This report reviews our current understanding of the habitat used by the Gulf of Mexico whale, at present and in the past, and considers the habitat that will be necessary for future recovery. It describes the importance of critical habitat for the species, relying on the best available science. The designation of critical habitat assists federal agencies in planning future actions by establishing areas that will be given special consideration in section 7 consultations under the ESA. The designation allows potential conflicts between development and listed species to be identified and avoided early in the planning process. (58 Fed. Reg. 29186, 29187 (May 19, 1983).) Prompt designation of critical habitat for the Gulf of Mexico whale is an essential step in protecting this high-risk population.
Marine mammals are under growing pressure as anthropogenic use of the ocean increases. Ship-strikes of large whales and loud underwater sound sources including airguns for marine geophysical prospecting and naval mid-frequency sonar are criticized for their possible negative effects on marine mammals. Competent authorities regularly require the implementation of mitigation measures, including vessel speed reductions or shut-down of acoustic sources if marine mammals are sighted in sensitive areas or in predefined exclusion zones around a vessel. To ensure successful mitigation, reliable at-sea detection of animals is crucial. To date, ship-based marine mammal observers are the most commonly implemented detection method, however thermal (IR) imaging based automatic detection systems have been used in recent years. This study evaluates thermal imaging-based automatic whale detection technology for its use across different oceans. The performance of this technology is characterized with respect to environmental conditions, and an automatic detection algorithm for whale blows is presented. The technology can detect whales in polar, temperate and subtropical ocean regimes over distances of up to several kilometers and outperforms marine mammal observers in the number of whales detected. These results show that thermal imaging technology can be used to assist in providing protection for marine mammals against ship-strike and acoustic impact across the world’s oceans.
This study focuses on the dolphins populating the water between Gibraltar and Algeciras in the south Iberian Peninsula, an area subjected to pressure due to high human activity. The area is considered an important feeding and breeding ground for common dolphins ( Delphinus delphis ). Due to the degree of residence of some specimens, and the large gap in knowledge about the evolution of wounds in D. delphis specimens with lacerations, this work sought to perform the following analyses: identify lacerated individuals; characterize sequences of ‘before – during – after’ with respect to the occurrence of lacerations; and associate the type of injury with its severity. This work will inform future studies by expanding a database on injured individuals and contribute to periodical monitoring of specimens that frequent these geographic areas. Between 2013 and 2017, we were able to track the healing process of five injured individuals of common dolphins from a whale-watching platform thanks to photo identification. The animals exhibited fresh external wounds from different sources. In the majority of individuals, the wound-healing processes lasted 3–21 weeks. The frequency with which sightings are made and knowledge about the local population will help track injured animals, follow their wound evolution, and document their survival rates. The documented injuries inflicted by human interactions described in this paper may include fishing interactions and propeller strikes, probably as a consequence of the high intensity of recreational fishing and whale-watching activities in the area.
Animal-borne electronic instruments (tags) are valuable tools for collecting information on cetacean physiology, behaviour and ecology, and for enhancing conservation and management policies for cetacean populations. Tags allow researchers to track the movement patterns, habitat use and other aspects of the behaviour of animals that are otherwise difficult to observe. They can even be used to monitor the physiology of a tagged animal within its changing environment. Such tags are ideal for identifying and predicting responses to anthropogenic threats, thus facilitating the development of robust mitigation measures. With the increasing need for data best provided by tagging and the increasing availability of tags, such research is becoming more common. Tagging can, however, pose risks to the health and welfare of cetaceans and to personnel involved in tagging operations. Here we provide 'best practice' recommendations for cetacean tag design, deployment and follow-up assessment of tagged individuals, compiled by biologists and veterinarians with significant experience in cetacean tagging. This paper is intended to serve as a resource to assist tag users, veterinarians, ethics committees and regulatory agency staff in the implementation of high standards of practice, and to promote the training of specialists in this area. Standardised terminology for describing tag design and illustrations of tag types and attachment sites are provided, along with protocols for tag testing and deployment (both remote and through capture-release), including training of operators. The recommendations emphasise the importance of ensuring that tagging is ethically and scientifically justified for a particular project and that tagging only be used to address bona fide research or conservation questions that are best addressed with tagging, as supported by an exploration of alternative methods. Recommendations are provided for minimising effects on individual animals (e.g. through careful selection of the individual, tag design and implant sterilisation) and for improving knowledge of tagging effects on cetaceans through increased post-tagging monitoring.
Geography has turned to towards the seas and oceans with much attention being paid to ‘water worlds’ through socio-cultural, political and environmental lenses. Geo-economic analysis, in particular, has considered the role of containerisation, the port, and logistics global flows central to the contemporary shipping industry. However, where routeing enters discussion these debates remain ‘surficial’ with a focus on the rationale of lines of connection which are mapped onto the sea (rather than into the sea, as a liquid, three-dimensional, motionful space). This paper challenges considerations of ship routeing that only skim the surface. This paper adds depth to the discussion. It is argued that ship routeing is not a purely surficial exercise of charting a voyage across seas and oceans. Routes have a geo-politics predicted at times on the water’s depth, the topography of the ocean floor and seabed and marine resources. Drawing on a variety of examples, notably the traffic routeing scheme – or ‘maritime motorway’ – governing the flows of shipping in the Dover Strait, UK, this paper brings a ‘wet ontology’ and three-dimensional analysis to ship routeing. It is contended that such a recognition and discussion of deep routeing is necessary to shed light upon the often invisible processes sea that underscore the global logistics flows vital to society and the economy.
More than 400 long-finned pilot whales, Globocephalus melas, stranded in Golden Bay, near Puponga (at the base of Farewell Spit) on 9 February 2017, followed by another pod of 200 on 11 February at Puponga. Although many of these whales were refloated by Department of Conservation staff and volunteers, restrandings occurred over the next 2 days, resulting in the death of a total of 252 whales. The northwestern corner of Golden Bay has long been the site of summer strandings of long-finned pilot whales. Public attitudes to stranded whales changed appreciably in the second half of the twentieth century, and instead of primarily welcoming dead whales as a source of food, oil and whalebone, attempts were made to keep stranded individuals alive and refloat them on the next high tide. The stranding event in February, 2017, although one of the largest on record, was otherwise typical of many in recent years. The reasons for strandings remain largely unknown, but public responses confirm sustained support for marine mammal conservation.
Since 2012, we have investigated a newly documented group of blue whales (Balaenoptera musculus sp.) in the
New Zealand region. Field research has focused on multi-disciplinary data collection regarding the ecology of blue
whales occurring in the South Taranaki Bight (STB) region of New Zealand (40.15 S, 173.30 W). The STB region
incurs significant anthropogenic activities from oil and gas exploration and extraction, fishing activities, vessel
traffic, and would also be affected by proposed seabed mining. Therefore, an improved understanding of the
population and ecological parameters of blue whales occurring in the STB and throughout New Zealand waters is
essential to develop appropriate and effective conservation management plans that mitigate impacts at individual
and population levels. Vessel-based field research in the STB was conducted during January and February of 2014,
2016, and 2017. Data collection focused on visual surveys to assess blue whale distribution patterns with concurrent
oceanographic and prey (krill) sampling, blue whale behavioral observations, photo-identification, tissue biopsy and
fecal sample collection, and health assessment through photogrammetric Unmanned Aerial System (UAS; drone)
operations. Additionally, a five-unit hydrophone array was deployed in the STB region in January 2016, which will
remain in place for two years to record blue whale vocalizations and ambient noise levels. Data analyses to date has
revealed the following significant findings: blue whales occur regularly in the STB to forage on krill; the population
consists of a minimum of 140 photo-identified individuals; blue whales occur in the STB region almost year-round
as described by vocalization detections at the five hydrophones of the New Zealand blue whale call; these whales
are most genetically similar to Australian ‘pygmy’ blue whales (B. m. brevicauda), with one unique mtDNA
haplotype identified and very low haplotype diversity; blue whales shift habitat use patterns across the STB region
relative to oceanographic patterns, as demonstrated by a markedly different distribution pattern in 2016 during an El
Niño event; individual blue whales re-occur within the STB and New Zealand waters inter-annually, including one
individual seen three times over a six-year period; blue whales likely also use the STB region as a nursing and
breeding area as indicated by behavioral observations and regular acoustic detection of the New Zealand blue whale
call. Many lines of evidence now lead us to hypothesize that these whales form a New Zealand population of blue
whales that are either resident or semi-resident in New Zealand waters. Continued data collection and analysis is
necessary to fill pressing knowledge gaps regarding the ecology of this blue whale population in order to inform
environmental management decisions.
Blue whales (Balaenoptera musculus) are distributed worldwide, and although severely depleted by commercial whaling, their abundance off the California coast now appears to be increasing. Little is known about natural causes of mortality of blue whales, but human-related mortality continues despite legal protection. Ship strikes are a significant mortality factor for other species of baleen whale, and changes in shipping traffic have been advocated to minimize further deaths. Between 1988 and 2007, 21 blue whale deaths were reported along the California coast, typically one or two cases annually. Three pulses in strand-ings were observed, with three carcasses observed in fall 1988, three in 2002, and four in fall 2007. Two of the four animals in 2007 were first observed dead in the Santa Barbara Channel and had wounds typical of a ship strike. Blue whale strandings were spatially associated with locations of shipping lanes, especially those associated with the Ports of Los Angeles and Long Beach, and were most common in the fall months.
Vessel strikes are the leading cause of mortality for the endangered North Atlantic right whale Eubalaena glacialis. Prior to a December 2008 implementation of a mandatory, seasonally based vessel-speed rule (10 knots, 18.5 km h -1) along the eastern US seaboard, voluntary recommended speeds and routes were established. We used Automatic Identification System (AIS) data to evaluate and compare the compliance rates between the mandatory and voluntary measures to protect right whales in the southeast US critical habitat area off Florida and Georgia during the winters from 2005-06 to 2008-09. Vessel compliance was significantly higher under mandatory versus voluntary recommended speed restrictions, with compliance rates of 75 and 16%, respectively. Average vessel speeds were slower under mandatory speed restrictions (10.5 knots, 19.6 km h -1) compared to voluntary recommended speed restrictions (14.5 knots, 26.9 km h -1). Although vessels only slow down when mandated, they change their routing voluntarily. Compliance rates with voluntary recommended routes steadily increased during this period, from 43% prior to rulemaking, to 52% during the first year, 84% in the second year, and 96% in the final year of the study. Combining reduced speeds with recommended routes reduces the probability of right whale mortality from ships by 71.9% from the pre-implementation period. These results support long-term implementation of both vessel-speed reduction and restricted vessel routes for the survival and recovery of the North Atlantic right whale.
Aerial surveys for Bryde's whales Balaenoptera cf. brydei were undertaken over the Hauraki Gulf and northeastern coast of New Zealand between 1999 and 2003. Whales were sighted in all months, with usually more whales seen in summer. The density of whales within the Hauraki Gulf was examined in relation to geographical location and sea surface temperatures. Whale densities were significantly higher in the inner parts of the Gulf, and in waters warmer than 14°C. Bryde's whales occurred along the entire northeastern coast from the Hauraki Gulf to North Cape, and tended to concentrate around headlands intersecting the East Australian Current. Whales were observed feeding, primarily on small fish, but crustaceans are probably also part of their local diet. The presence of calves in the survey area indicated a late winter to early spring calving season in New Zealand waters or the nearby oceanic Pacific. Short-beaked common dolphins Delphinus delphis and common bottlenose dolphins Tursiops truncatus associated with Bryde's whales in feeding workups, that were also attended by gannets Morus serrator, shearwaters and petrels (Procellariidae), and terns (Laridae). Bryde's whale habitat in the Hauraki Gulf coincides with shipping lanes, and a number of these whales have been struck and killed by large vessels in recent years.
Collisions between ships and whales are an increasing concern for endangered large whale species. After an unusually high number of blue whales (Balaenoptera musculus) were fatally struck in 2007 off the coast of southern California, federal agencies implemented a voluntary conservation program to reduce the likelihood of ship-strikes in the region. This initiative involved seasonal advisory broadcasts requesting vessel operators to voluntarily slow to 10 knots or less when transiting a 75 nm stretch of designated shipping lanes. We monitored ship adherence with those speed advisories using Automatic Identification System data. Daily average speed of cargo and tanker ships and the average speed of individual ship transits before, during, and after the notices were statistically analyzed for changes related to the notices. Whereas a small number of individual ships (1%) traveled significantly slower during the requested periods, speeds were not at or below the recommended 10 knots, nor were daily average speeds reduced during the notices. Voluntary conservation measures are established in a variety of contexts, and may be preferable to regulatory action; in this case, a request to make voluntary changes appeared largely ineffective. Reducing collision risks for whales in this area will require consideration of the various factors that likely explain the lack of adherence when developing an alternative strategy.
A key component in understanding the ecological role of marine mammal predators is to identify how, where and how much prey they capture in time and space. Satellite and archival tags on pinnipeds generally only provide diving and positioning information, and foraging is often inferred to take place in particular shaped dives or when the animal remains in an area for an extended interval. However, fast movements of the head and jaws may provide reliable feeding cues that can be detected by small low-power accelerometers mounted on the head. To test this notion, a harbour seal (Phoca vitulina) was trained to wear an OpenTag (sampling at 200 or 333 Hz with ±2 or ±16 g clipping) on its head while catching fish prey in front of four underwater digital high-speed video cameras. We show that both raptorial and suction feeding generate jerk (i.e., differential of acceleration) signatures with maximum peak values exceeding 1000 m/s3. We conclude that reliable prey capture cues can be derived from fast-sampling, head mounted accelerometer tags thus holding a promising potential for long-term studies of foraging ecology and field energetics of aquatic predators in their natural environments.
U.S. national marine sanctuaries are federally designated marine protected areas that are often located in highly productive waters. This makes these sanctuaries important to a diverse, economically vital human user community and for biodiversity conservation. As a result, appropriate sanctuary management must balance conflicting goals. Fortunately, sanctuaries have been early adapters in marine planning. Marine planning is a transparent, ecosystem-based, science-driven decision making process developed with a high level of stakeholder and public involve-ment. As established marine planning practitioners, national marine sanctuaries can provide valuable case studies and insights. Marine Planning in Action for example, the National Oceanic and Atmospheric Administration's (NOAA) Stellwagen Bank National Marine Sanctuary, an 852-square-mile marine pro-tected area located off the coast of Massachusetts and New Hampshire, hosts some of the largest aggrega-tions of endangered large whales (such as the hump-back, fin, and North Atlantic right whales). However, the Boston Traffic Separation Scheme (BTSS), a major shipping route, transits it. Because of its close proximity to transiting ships, the area has become a "hot spot" for collisions between vessels and whales. To reduce incidents in the sanctuary and surrounding waters we used a marine planning process.
Acoustic recordings of baleen whale calls were analysed for the calendar year 1997 from a pair of fixed hydrophones located 5 km east of Great Barrier Island, New Zealand. The primary goal of the study was to examine blue whale seasonally and song type as part of a larger worldwide study. Calls were recorded from blue whales of two song types, fin whales, humpback whales, Bryde's whales, and of two unknown call types, each probably produced by Bryde's whales. The peak of calling density was May through September for the blue, fin, and humpback whales. The known Bryde's whale calls occurred year‐round and the probable Bryde's whale calls occurred from May through December. Blue whale songs of a type so far known only from New Zealand waters were detected within 2 km of shore and occurred four times from June to December, whereas the Southern Ocean blue whale songs were detected only further offshore in mid‐winter. Bryde's whale calls were the most abundant type and often occurred near the hydrophones. These data provide a baseline from which future recordings from the same hydrophones could be compared.
Fifty-four right whale mortalities have been reported from between Florida, USA and the Canadian Maritimes from 1970 to 2002. Th irty of those animals were examined: 18 adults and juveniles, and 12 calves. Morphometric data are presented such that prediction of body weight is possible if the age, or one or more measurements are known. Calves grew approximately linearly in their first year. T otal length and fluke width increased asymptotically to a plateau with age, weight increased linearly with age, weight and snout to blowhol e distance increased exponentially with total length, whereas total length was linearly related to fluke width and flipper length. Among t he adults and juveniles examined in this study, human interaction appeared to be a major cause of mortality, where in 14/18 necropsies, traum a was a significant finding. In 10/14 of these, the cause of the trauma was presumed to be vessel collision. Entanglement in fishing ge ar accounted for the remaining four cases. Trauma was also present in 4/12 calves. In the majority of calf mortalities (8/12) the cause of d eath was not determined. Sharp ship trauma included propeller lacerations inducing multiple, deep lacerations that often incised vital organ s including the brain, spinal cord, major airways, vessels and musculature. Blunt ship trauma resulted in major internal bruising and fract ures often without any obvious external damage. In at least two cases fatal gear entanglements were extremely protracted: where the entang lements took at least 100 and 163 days respectively to be finally lethal. The sum of these findings show two major needs: (1) that exti nction avoidance management strategies focused on reducing trauma to right whales from ship collisions and fishing gear entanglement a re highly appropriate and need to be continued and; (2) that as mitigation measures continue to be introduced into shipping and fishing i ndustry practices, there is a strong effort to maximise the diagnostic quality of post-mortem examination of right whale mortalities, t o ensure an optimal understanding of resultant trends.
Defining the appropriate scale over which to conduct a study in the marine environment is critical to achieving appropriate scientific, management, mitigation and conservation objectives. This paper focuses on applications of passive acoustic technologies over a range of spatial and temporal scales. It is divided into sections dealing with archival and real-time passive acoustic sensor applications. Each section assesses the principles behind using the respective technology and pro- vides recent examples of research and management applications for marine mammals and fish. The section on archival sensors highlights the need for continued development of automated acoustic detectors to assess large data sets. Case studies are presented of detectors developed for determining seasonal occurrence and distribution of haddock sounds and humpback whale vocalizations. Also presented are studies of other applications using archival sensors: tracking singing humpback whales in Brazil, using vocalizations to assess the reproductive strategies of Arctic bearded seals and assessing regional variability in call patterns for North Atlantic right whales. The section on real-time passive acoustic sensors focuses on real-time buoys and towed arrays. Case studies presented include a real-time buoy system used for monitoring endangered North Atlantic right whales and a station- ary autonomous array providing real-time access to Antarctic acoustic data. The value of using towed arrays for real-time applications is also assessed, and a case study is provided on the use of towed arrays to improve abundance estimates of North Pacific cetaceans and to better understand vocaliza- tion behaviors.
Although collisions with motorized ships are a recognized source of whale mortality, little has been done to compile information on the frequency of their occurrence or contributing factors. We searched historical records and computerized stranding databases for evidence of ship strikes involving great whales (i.e., baleen whales and the sperm whale). Historical records suggest that ship strikes fatal to whales first occurred late in the 1800s as ships began to reach speeds of 13-15 kn, remained infrequent until about 1950, and then increased during the 1950s-1970s as the number and speed of ships in-creased. Of 11 species known to be hit by ships, fin whales (Balaenoptera physalus) are struck most frequently; right whales (Eubalae1la glacialis and E. allStralis), humpback whales (Megaptera novaeangliae), sperm whales (Physeter catodon), and gray whales (Eschrichtius robustllS) are hit commonly. In some areas, one-third of all fin whale and right whale strandings appear to involve ship strikes. To assess contributing factors, we compiled descriptions of 58 collisions. They indicate that all sizes and types of vessels can hit whales;
Vessel strikes are the primary source of known mortality for the endangered North Atlantic right whale (Eubalaena glacialis). Multi-institutional efforts to reduce mortality associated with vessel strikes include vessel-routing amendments such as the International Maritime Organization voluntary "area to be avoided" (ATBA) in the Roseway Basin right whale feeding habitat on the southwestern Scotian Shelf. Though relative probabilities of lethal vessel strikes have been estimated and published, absolute probabilities remain unknown. We used a modeling approach to determine the regional effect of the ATBA, by estimating reductions in the expected number of lethal vessel strikes. This analysis differs from others in that it explicitly includes a spatiotemporal analysis of real-time transits of vessels through a population of simulated, swimming right whales. Combining automatic identification system (AIS) vessel navigation data and an observationally based whale movement model allowed us to determine the spatial and temporal intersection of vessels and whales, from which various probability estimates of lethal vessel strikes are derived. We estimate one lethal vessel strike every 0.775-2.07 years prior to ATBA implementation, consistent with and more constrained than previous estimates of every 2-16 years. Following implementation, a lethal vessel strike is expected every 41 years. When whale abundance is held constant across years, we estimate that voluntary vessel compliance with the ATBA results in an 82% reduction in the per capita rate of lethal strikes; very similar to a previously published estimate of 82% reduction in the relative risk of a lethal vessel strike. The models we developed can inform decision-making and policy design, based on their ability to provide absolute, population-corrected, time-varying estimates of lethal vessel strikes, and they are easily transported to other regions and situations.
For protected reserves set aside for conservation, the impact of roads and traffic on wildlife can be severe, particularly for those in the peri-urban environment. Often reserves possess many sealed roads that have regular traffic from tourists and local residents. As managerial bodies struggle to control the wide variety of threats to the fauna within these reserves, the loss of life on roads only compounds the precarious nature of wildlife survival in these dis-turbed environments. As a first step to addressing this concern in Australia, this study quantifies the fatalities of wildlife killed on roads within the Royal National Park in New South Wales, and estimates those wildlife species using roadside habitat in order to iden-tify species susceptible to collisions. Modelling of fatality data indicated that mammals were most likely to be killed where forage was abundant on the roadside verge and where there was plenty of protective cover, while birds were most likely to be killed when the height of roadside vegetation was low. A number of collision hotspots were identified along the surveyed road that should be the target of mitigation efforts. The average speed of vehi-cles travelling within the park peaked at night. This is of particular concern as activity by Australian mammals tends to be greatest at night. The findings indicate that roads in peri-urban reserves have the potential to alter the movement of animals and impact on their populations through loss of life.
The conservation status of New Zealand (NZ) marine mammals (suborders Cetacea and
Pinnipedia) is reappraised using the 2008 version of the NZ Threat Classification System. The
list comprises 56 taxa (named species or subspecies, and as yet unnamed forms or types) in the
following categories: Threatened*eight taxa (five Nationally Critical and three Nationally
Endangered); Vagrant*six taxa; Migrant*20 taxa; and Data Deficient*13 taxa. A further nine
taxa are listed as Not Threatened. Relative to the previous listing, the threat status of two species
worsened: the NZ sea lion (Phocarctos hookeri) was uplisted to Nationally Critical and the
bottlenose dolphin (Tursiops truncatus) was uplisted to Nationally Endangered. No species was
considered to have an improved status. With the uplisting of the NZ sea lion and the continued
listing of the Hector’s dolphin (Cephalorhynchus hectori hectori) as Endangered and Maui’s
dolphin (C. hectori maui) as Nationally Critical, all three endemic NZ marine mammals are now
considered threatened with extinction. We considered future research or management actions
that would allow the downlisting of the eight taxa currently listed as Threatened.
Rorqual baleen whales lunge feed by engulfment of tons of prey-laden water in a large and expandable buccal pouch. According to prior interpretations, feeding rorquals are brought to a near-halt at the end of each lunge by drag forces primarily generated by the open mouth. Accelerating the body from a standstill is energetically costly and is purported to be the key factor determining oxygen consumption in lunge-feeding rorquals, explaining the shorter dive times than expected given their sizes. Here, we use multi-sensor archival tags (DTAGs) sampling at high rates in a fine-scale kinematic study of lunge feeding to examine the sequence of events within lunges and how energy may be expended and conserved in the process of prey capture. Analysis of 479 lunges from five humpback whales reveals that the whales accelerate as they acquire prey, opening their gape in synchrony with strong fluke strokes. The high forward speed (mean depth rate: 2.0±0.32 m s(-1)) during engulfment serves both to corral active prey and to expand the ventral margin of the buccal pouch and so maximize the engulfed water volume. Deceleration begins after mouth opening when the pouch nears full expansion and momentum starts to be transferred to the engulfed water. Lunge-feeding humpback whales time fluke strokes throughout the lunge to impart momentum to the engulfed water mass and so avoid a near or complete stop, but instead continue to glide at ~1-1.5 m s(-1) after the lunge has ended. Subsequent filtration and prey handling appear to take an average of 46 s and are performed in parallel with re-positioning for the next lunge.
Ship strikes of large whales cause mortalities worldwide, but there is uncertainty regarding the frequency and species involved. We examined 130 records (from 1980–2006) of large whale strandings in Washington State. Nineteen strandings (seven species) had evidence of ship-strikes. Fin whales (Balaenoptera physalus) had the highest incidence of ante-mortem ship strike (five of seven, with the remaining two possibly post-mortem) and all but one occurring since 2002. Six grey whales (Eschrichtius robustus) suffered ‘possible ship strike’ injuries, likely the result of their large numbers in the area, rather than high levels of ship strikes. Only one possible ship-struck humpback whale was recorded, despite concentrations of humpbacks feeding within shipping lanes in this region. This study shows dramatic differences in occurrences of ship-struck large whales by species, which we believe results from a combination of species' vulnerability to ship strikes, and how likely a struck whale is to be caught up on the bow of a ship and brought to waters where it can be examined.
United States and Canadian governments have responded to legal requirements to reduce human-induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause-specific mortalities with time. We compared the number of human-caused mortalities with U.S. federally established levels of potential biological removal (i.e., species-specific sustainable human-caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel-strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel-strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population-range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife-management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality-driven conservation issues.
Evaluación del Manejo para Mitigar Efectos Antropogénicos sobre Ballenas Mayores
Resumen
Los gobiernos de Estados Unidos y Canadá han respondido a requerimientos legales para reducir la mortalidad de ballenas inducida por humanos por medio de impacto con embarcaciones y enmarañamiento en artes de pesca mediante la implementación de un conjunto de acciones reguladoras. Analizamos los patrones espaciales y temporales de la mortalidad de ballenas mayores en el Atlántico Noroccidental (23.5°N a 48.0°N), de 1970 a 2009, en el contexto de cambios de manejo. Utilizamos un modelo logístico multinomial ajustado por la máxima probabilidad de detección de tendencias en mortalidades por causa específica en el tiempo. Comparamos el número de muertes provocadas por humanos con los niveles de remoción biológica potencial (i.e., mortalidad específica provocada por humanos sustentable). De 1970 a 2009, hubo 1762 muertes (conocidas) y lesiones serias (casi fatales) involucrando 8 especies de ballenas mayores. Determinamos la causa de 43% de todas las muertes; de ellas, 67% (502) resultaron de interacciones humanas. El enmarañamiento en artes de pesca fue la causa principal de muerte en todas las especies (n = 323), seguida de causas naturales (n = 248) e impacto de embarcaciones (n = 171). Los niveles sustentables de mortalidad establecidos fueron excedidos consistentemente hasta en 650% en 2 especies. Las probabilidades de muerte por enmarañamiento y por impacto de embarcaciones incrementaron significativamente de 1990 a 2009. No hubo cambio significativo en la intensidad local de mortalidad por todas las causas o por impacto de embarcaciones antes y después de 2003, año en el que se implementaron numerosos esfuerzos de mitigación. Hasta ahora, los esfuerzos regulatorios no han reducido los efectos letales de las actividades humanas sobre las ballenas a nivel de población, aunque no excluimos la posibilidad de éxito de medidas enfocadas a hábitats locales específicos que no estuvieron dentro de la resolución de nuestro análisis. No es claro como se relacionan con nuestros resultados las deficiencias en el diseño o implementación del manejo. Análisis como el que realizamos son cruciales para la evaluación crítica de decisiones para el manejo de vida silvestre, y los resultados de estos análisis pueden proporcionar directrices a los manejadores para que modifiquen medidas regulatorias y puedan ser aplicadas globalmente en temas de conservación relacionadas con mortalidad.
Northern right whales in the western North Atlantic number about 300 animals and have shown little sign of recovery in recent decades. Mortality and serious injury due to human activities, particularly commercial fishing and shipping, are thought to be significant factors limiting their recovery. From 1970-1999, 45 right whale deaths were reliably documented. Sixteen of these fatalities (35.5%) were due to ship collisions, and three (6.7%) were due to entanglement in fishing gear. The remainder were neonates (13; 28.9%) and 'unknown cause' mortalities (13; 28.9%). Criteria for defining serious injuries and mortalities from entanglement or ship strikes were developed and include any animal carrying fishing gear, cuts from entanglement or ship strike deeper than 8cm, swelling or necrosis, evidence of poor health from such interactions, and, in carcasses, evidence of haematoma, haemorrhaging or broken bones. A total of 56 animals fitting the defined criteria were documented from 1970-1999: 31 (55.4%) from entanglement and 25 (44.6%) from ship strikes. Nineteen were fatal (16 ship strikes, 3 entanglements), 10 were possibly fatal (2 ship strikes, 8 entanglements) and 27 were non-fatal (7 ship strikes, 20 entanglements). The breakdown of potentially serious injuries by age and sex reveals no difference in levels between sexes but shows a 3.3:1 higher level of interaction in juveniles and calves versus adults. The data show that ship strikes are more immediately lethal, but entanglements can result in long term deterioration of an animal and may be responsible for higher levels of mortality than previously thought. Considering that some animals become entangled, drown and never return to the surface, even these levels may be underestimated. Between 1986 and 1999, 84 animals were presumed dead based on a lack of resightings for six years. There were 32 confirmed deaths during this time period suggesting that at least as many unreported deaths occurred as carcasses were reported. Definitive actions need to be taken to reduce the level and severity of anthropogenic injuries and deaths. Actions could include continued disentanglement efforts, gear modifications, seasonal closures for fisheries, mandatory ship reporting, ships' routing measures and speed restrictions for commercial shipping.
All endangered large whale species are vulnerable to collisions with large ships; and "ship strikes" are the greatest known threat to one of the world's rarest whales, the North Atlantic right whale (Eubalaena glacialis). The magnitude of this threat is likely to increase as maritime commerce expands. Factors influencing the incidence and severity of ship strikes are not well understood, although vessel speed appears to be a strong contributor. The purpose of this study was to characterize the hydrodynamic effects near a moving hull that may cause a whale to be drawn to or repelled from the hull, and to assess the accelerations exerted on a whale at the time of impact. Using scale models of a container ship and a right whale in experimental flow tanks, we assessed hydrodynamic effects and measured accelerations experienced by the whale model in the presence of a moving vessel. Accelerations at impact were measured while the whale was at the surface, for various vessel speeds, orientations of the whale relative to the vessel path, and distances off the direct path of the vessel. Accelerations experienced by the whale model in a collision: increased in magnitude with increasing ship speed; were not dependent on whale orientation to the vessel path; and decreased exponentially with increasing separation distances from the ship track. Subsequent experiments with the whale model submerged at one to two times the ship's draft indicated a pronounced propeller suction effect, a drawing of the whale toward the hull, and increased probability of propeller strikes resulting from this class of encounter. Measured accelerations are a proxy for impact severity, but do not constitute a detailed study of injury mechanism in a living animal, though they may help inform future work. We present a heuristic map of the hydrodynamic field around a transiting hull likely involved in close whale/ vessel encounters. These results may have bearing on policy decisions, particularly those involving vessel speed, aimed at protecting large whales from ship strikes worldwide. Published by Elsevier B.V.
