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Introduction
Lars Bejder is the Director of the Marine Mammal Research Program at the Hawaii Institute of Marine Biology at the University of Hawaii. He has studied various aspects of cetacean biology, ecology and conservation in New Zealand, Australia and US. He has published > 150 peer-reviewed journal articles and book chapters on cetaceans (impacts of human activity; fundamental biology and ecology; statistical methods to analyse complex social structures).
Current institution
Additional affiliations
January 2018 - April 2022
June 2014 - December 2017
August 1999 - January 2005
Publications
Publications (247)
Studies evaluating effects of human activity on wildlife typically emphasize short-term behavioral responses from which it is difficult to infer biological significance or formulate plans to mitigate harmful impacts. Based on decades of detailed behavioral records, we evaluated long-term impacts of vessel activity on bottlenose dolphins (Tursiops s...
1. Linking key ecological characteristics with animal behaviour is essential for identifying and protecting important habitats that support life functions. Spinner dolphins display a predictable diurnal behavioural pattern where they forage offshore at night and return to sheltered bays during daytime to rest. These bays, which are also subject to...
Anthropogenic impacts on marine systems are increasing in frequency, geographic range and severity. While changes in climate will likely lead to the greatest impacts at the system-level, for marine megafauna, entanglement in marine debris also constitutes a pernicious threat. For baleen whales, in regions where high productivity and prolific fisher...
Several legal acts mandate that management agencies regularly assess biological populations. For species with distinct markings, these assessments can be conducted noninvasively via capture‐recapture and photographic identification (photo‐ID), which involves processing considerable quantities of photographic data. To ease this burden, agencies incr...
Given recent declines in North Pacific humpback whale (Megaptera novaeangliae) reproductive output and calf survival, there is additional urgency to better understand how mother–calf pairs allocate energy resources across their migratory cycle. Here, unoccupied aerial system (UAS; or drone) photogrammetry was used to quantify the body size and cond...
Improving our understanding of energy allocation in reproduction is key for accurately parameterizing bioenergetic models to assess population responses to environmental perturbations and anthropogenic disturbance. We quantified the energetic cost of gestation in humpback whales (Megaptera novaeangliae) using historical whaling records, non‐invasiv...
Several animal species use tools for foraging; however, very few manufacture and/or modify those tools. Humpback whales, which manufacture bubble-net tools while foraging, are among these rare species. Using animal-borne tag and unoccupied aerial system technologies, we examine bubble-nets manufactured by solitary humpback whales (Megaptera novaean...
Assessing trends in population abundance and demographics is crucial for managing long‐lived and slow‐reproducing species. Obtaining demographic data, and age‐structure information, is challenging, notably for cetaceans. To address this, we combined Unoccupied Aerial System (UAS; drone) photogrammetry data with long‐term (>20 years) photo identific...
ABSTRACT: Studying underwater soundscapes of critical habitats of marine mammals can provide valuable information on the acoustic environment utilized by sound-reliant animals. For the endangered Hawaiian monk seal Neomonachus schauinslandi (HMS), the acoustic scene of their aquatic habitats is poorly understood. We measured ambient noise levels an...
Spinner dolphins (Stenella longirostris subsp.) occupy the nearshore waters of several Hawaiian Islands. Due to their constrained behavioral pattern and genetic isolation, they are vulnerable to anthropogenic threats. Their occurrence and behavior are well-described, yet a lack of data on their abundance and survival rates hinders optimal conservat...
For the 40 years after the end of commercial whaling in 1976, humpback whale populations in the North Pacific Ocean exhibited a prolonged period of recovery. Using mark–recapture methods on the largest individual photo-identification dataset ever assembled for a cetacean, we estimated annual ocean-basin-wide abundance for the species from 2002 thro...
The sensory mechanisms used by baleen whales (Mysticeti) for locating ephemeral, dense prey patches in vast marine habitats are poorly understood. Baleen whales have a functional olfactory system with paired rather than single blowholes (nares), potentially enabling stereo-olfaction. Dimethyl sulfide (DMS) is an odorous gas emitted by phytoplankton...
Passive acoustic monitoring is an effective technique for studying cetacean presence within marine protected areas (MPAs). The Hawaiian archipelago is home to 18 species of resident toothed whales, but little is known regarding the spatio-temporal variability of false killer whales (Pseudorca crassidens—FKW) and short-finned pilot whales (Globiceph...
Researchers can investigate many aspects of animal ecology through noninvasive photo–identification. Photo–identification is becoming more efficient as matching individuals between photos is increasingly automated. However, the convolutional neural network models that have facilitated this change need many training images to generalize well. As a r...
Understanding the population health status of long-lived and slow-reproducing species is critical for their management. However, it can take decades with traditional monitoring techniques to detect population-level changes in demographic parameters. Early detection of the effects of environmental and anthropogenic stressors on vital rates would aid...
We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for most living individual humpback whales (Megaptera novaeangliae) in the North Pacific Ocean. The dataset was built through a broad collaboration combining 39 separate curated photo-ID catalogs, supplemented with community sc...
Quantifying the energy expenditure of animals is critical to understand the cost of anthropogenic disturbance relative to their overall energy requirements. We used novel drone focal follows (776 follows, 185 individuals) and aerial photogrammetry (5,372 measurements, 791 individuals) to measure the respiration rate and body condition loss of south...
We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for the majority of living individual humpback whales ( Megaptera novaeangliae ) in the North Pacific Ocean. The dataset was built through a broad collaboration combining 39 separate curated photo-ID catalogs supplemented with...
We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for most living individual humpback whales ( Megaptera novaeangliae ) in the North Pacific Ocean. The dataset was built through a broad collaboration combining 39 separate curated photo-ID catalogs, supplemented with community...
No PDF available
ABSTRACT
False killer whales (Pseudorca crassidens) and short-finned pilot whales (Globicephala macrorhynchus) are resident, toothed whale species to the Hawaiian archipelago. False killer whales are considered of high concern in Hawai‘i with the insular population listed as endangered. Passive acoustic monitoring (PAM) is an effec...
No PDF available
ABSTRACT
Describing underwater soundscapes of critical habitats of marine mammals can provide valuable information on the acoustic environment utilized by sound-reliant animals. For the endangered Hawaiian monk seal (Neomonachus schauinslandi), whose underwater hearing abilities and vocal communication were recently described, the...
Although gigantic body size and obligate filter feeding mechanisms have evolved in multiple vertebrate lineages (mammals and fishes), intermittent ram (lunge) filter feeding is unique to a specific family of baleen whales: rorquals. Lunge feeding is a high cost, high benefit feeding mechanism that requires the integration of unsteady locomotion (i....
Wildlife management requires reliable demographic information to assess the status of a population and its vulnerability to threats. This study calculated age class‐ and sex‐specific demographic parameters and assessed the viability of a community of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) resident to the Peel‐Harvey Estuary in Western...
Tourism and recreational activities now threaten the conservationConservation status of 21% of the marine mammalMarine mammals species recognized by the IUCN. In the past two decades, concerted efforts have been made to better understand the biological relevance of behavioral responses of marine mammals to whale-watchingWhale watchingdisturbanceDis...
Background
The reef manta ray ( Mobula alfredi ) is a globally threatened species and an iconic tourist attraction for visitors to Indonesia’s Komodo National Park (NP). In 2013, manta ray fishing was banned in Komodo NP and its surroundings, preceding the nationwide manta ray protection in 2014. Over a decade ago, a previous acoustic telemetry stu...
Climate change is a global phenomenon, yet impacts on resource availability to predators may be spatially and temporally diverse and asynchronous. As capital breeders, whales are dependent on dense, predictable prey resources during foraging seasons. An Unusual Mortality Event (UME) of Eastern North Pacific (ENP) gray whales (Eschrichtius robustus)...
Animal body size and growth patterns play important roles in shaping the life history of species. Baleen whales include the largest animals on the planet, with somatic growth costs expected to be substantial. We used unmanned aerial vehicle photogrammetry and long-term
individual sighting histories from photo identification (1991−2019) to estimate...
The cost of reproduction greatly affects a species’ life history strategy. Baleen whales exhibit some of the fastest offspring growth rates in the animal kingdom. We quantified the energetic cost of gestation for southern right whales (Eubalaena australis) by combining whaling catch records of pregnant females with photogrammetry data on southern r...
Food provisioning promotes close interaction with wildlife but can negatively impact the targeted species. Repeated behavioural disruptions have the potential to negatively impact vital rates and have population level consequences. In Bunbury, Western Australia, food-provisioned female bottlenose dolphins, Tursiops aduncus, suffer reduced reproduct...
Despite their enormous size, whales make their living as voracious predators. To catch their much smaller, more maneuverable prey, they have developed several unique locomotor strategies that require high energetic input, high mechanical power output and a surprising degree of agility. To better understand how body size affects maneuverability at t...
Understanding species’ distribution patterns and the environmental and ecological interactions that drive them is fundamental for biodiversity conservation. Data deficiency exists in areas that are difficult to access, or where resources are limited. We use a broad-scale, non-targeted dataset to describe dolphin distribution and habitat suitability...
• Investigations of population structure across multiple niche dimensions can identify discrete management units within populations. This study examined social, spatial and isotopic niche partitioning in Indo-Pacific bottlenose dolphins (Tursiops aduncus) across ca. 600 km² of coastal and estuarine waters in south-western Australia, to evaluate whe...
Conspecifics may vary in their space use and diet leading to niche partitioning within populations. In social species, such partitioning may correspond to social structure as closely associated individuals likely encounter the same resources. This study investigated whether space use and diet varied among social clusters of a resident estuarine pop...
Major progress has been made since the publication of noise exposure criteria by Southall et al. (2007) in addressing the probability and severity of marine mammal behavioral responses to measured noise exposures. New methodological developments for studying behavioral responses have broadened the spatial, temporal, and population scales of potenti...
Documented cases of cetacean births in the wild are rare. While there are currently no direct observations of a complete humpback whale birth, they are one of the few large whale species where observers have been present during a birthing event. We compiled eye-witnessed accounts of all known humpback whale birthing events and found nine well-docum...
Kelp gulls Larus dominicanus (KG) feed on the skin and blubber of living southern right whales Eubalaena australis (SRWs) off Península Valdés (PV), Argentina. The whales respond strongly to KG micropredation by changing their immediate (acute) behavior during attacks and their overall (chronic) surfacing pattern and body posture to minimize gull e...
Understanding the impacts of foraging disruptions to odontocete body condition is fundamental to quantifying biological effects of human disturbance and environmental changes on cetacean populations. Here, reductions in body volume of free-ranging pygmy killer whales (Feresa attenuata) were calculated using repeated measurements of the same individ...
Insights into the food habits of predators are essential for maintaining healthy predator populations and the functioning of ecosystems. Stomach content and stable isotope analyses were used to investigate the foraging habits of an apex predator, the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in south-western Australia. A total of 2,594 pre...
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Marine wildlife tourism attractions often use food rewards to ensure close-up encounters withfree-ranging animals. In Bunbury, Western Australia, the Dolphin Discovery Centre (DDC) conductsa food-provision program where bottlenose dolphins (N= 22; between 2000-2018) are offered foodrewards to encourage their visitation at a beach in front of the DD...
The effect of nature-based tourism on wildlife has been the focus of much attention. Studies have demonstrated how boat-based cetacean-watching tourism can cause both short-term and long-term effects on targeted populations. However, limited attention has been given to the effect of swim-with activities on humpback whales (Megaptera novaeangliae)....
Increasing human activity along the coast has amplified the extinction risk of inshore delphinids. Informed selection and prioritisation of areas for the conservation of inshore delphinids requires a comprehensive understanding of their distribution and habitat use. In this study, we applied an ensemble species distribution modelling approach, comb...
Wild dolphin-swim tourism has grown in specific locations where Hawaiian spinner dolphins (Stenella longirostris) have known resting habitat. The increased growth in dolphin-swim businesses has created an industry in Hawaii that earns an estimated $102 million (USD) annually in 2013. Semi-structured interviews with business owners, market research,...
Unmanned aerial vehicles (UAVs) are increasingly used for wildlife research and monitoring, but little information exists on their potential effect on marine mammals. We assessed the effects of a UAV on the behavior of southern right whales (Eubalaena australis) in Australia. Focal follows of ten right whale mother‐calf pairs were conducted using a...
The North Atlantic right whale Eubalaena glacialis (NARW), currently numbering <410 individuals, is on a trajectory to extinction. Although direct mortality from ship strikes and fishing gear entanglements remain the major threats to the population, reproductive failure, resulting from poor body condition and sublethal chronic entanglement stress,...
Human activities and anthropogenic environmental changes are having a profound effect on biodiversity and the sustainability and health of many populations and species of wild mammals. There has been less attention devoted to the impact of human activities on the welfare of individual wild mammals, although ethical reasoning suggests that the welfa...
Swim-with-whale tourism is a lucrative and rapidly growing industry worldwide. Whale-watching can cause negative effects on the behaviour of targeted animals. Although this is believed to be particularly true for close-up interactions, such as swim-with operations, few empirical studies have investigated this. In 2016, the Western Australian State...
The eastern North Pacific gray whale Eschrichtius robustus experienced an unusual mortality event (UME) in 2019-2020, with 384 whales found dead along the Pacific coasts of Mexico, USA and Canada. A similar UME in 1999-2000 was speculated to have been caused by starvation, but body condition data were not available to test this hypothesis. Between...
Abstract:
The viability of populations depends on metapopulation dynamics: the combination of reproduction and mortality within populations, as well as dispersal between populations. Population viability is also dependent on genetic diversity, which is essential for populations to adapt to environmental change. This study focuses on an Indo-Pacific...
Place‐based management can be an effective conservation tool to protect cetaceans from anthropogenic pressures. The spatial use of the world's second largest population of the threatened Indo‐Pacific humpback dolphins ( Sousa chinensis ) is not well‐documented, which makes it challenging to designate protected areas for this population.
To address...
Integrating Emerging Technologies into Marine Megafauna Conservation Management
Many recent and emerging technological innovations hold great potential to transform the “best-available science” for marine megafauna conservation management, such as remote sensing, telemetry, molecular technologies, unmanned aerial vehicles, bio-acoustics, and anima...
Most baleen whales migrate to low-latitude breeding grounds during winter to give
birth and nurse their calves during the early stages of growth and development. While mothers
invest a large amount of energy into the early development of their calves, the time allocated to
important behaviours associated with maternal care (e.g. nursing) as well as...
Obtaining morphometric data on free-ranging marine megafauna is difficult, as traditional methods rely on post-mortem or live-capture techniques. We linked stereo-laser photogrammetry with long-term demographic data to compare length-at-age (LaA) growth curves of two well-studied populations of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in...
Southern right whales (Eubalaena australis) invest substantial amounts of energy in their calves, while facing the risk of having them predated upon by eavesdropping killer whales (Orcinus orca). We tested the hypothesis that southern right whale mother-calf pairs employ acoustic crypsis to reduce acoustic detectability by such predators. Specifica...
Abstract Food-provisioning of wildlife can facilitate reliable up-close encounters desirable by tourists and, consequently, tour operators. Food-provisioning can alter the natural behavior of an animal, encouraging adverse behavior (e.g. begging for food handouts), and affect the reproductive success and the viability of a population. Studies linki...
Manlik, O., Krützen, M., Kopps, A. M., Mann, J., Bejder, L., Allen, S. J., Frere, C., Connor, R.C., Sherwin, W. B. (2019). Data from: Is MHC diversity a better marker for conservation than neutral genetic diversity? A case study of two contrasting dolphin populations. Dryad Digital Repository. https ://doi.org/10.5061/dryad.73k278d
Genetic diversity is essential for populations to adapt to changing environments. Measures of genetic diversity are often based on selectively neutral markers, such as microsatellites. Genetic diversity to guide conservation management, however, is better reflected by adaptive markers, including genes of the major histocompatibility
complex (MHC)....
This is the supplementary material to the article "Is MHC diversity a better marker for conservation than neutral genetic diversity? A case study of two contrasting dolphin population" (Manlik et al. 2019)
Manta rays (Mobula spp.) are highly valued in nature-based tourism globally. In Indonesia, although manta rays are protected, critical information is lacking on their habitat use, population dynamics and movements. We investigate the population structure and residency patterns of reef manta rays (Mobula alfredi) in the Nusa Penida Marine Protected...
Understanding individual interactions within a community or population provides valuable insight into its social system, ecology, and, ultimately, resilience against external stimuli. Here, we used photo-identification data, generalized affiliation indices, and social network analyses to investigate dyadic relationships, assortative interactions, a...
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 D...
Understanding the factors that contribute to a population’s habitat use is important for conservation planners and managers to identify reasons behind a population’s distribution. Habitat use often differs between sexes, however few studies on sexually monomorphic species document this difference, resulting in misleading ecological interpretations...
Habitat selection is strongly influenced by spatial variations in habitat quality and predation risk. Repeated exposure of wildlife to anthropogenic activities in important habitats may affect habitat selection, leading to negative biological consequences. We quantified the cumulative human exposure of a small, genetically isolated and behaviourall...
The forecast for the viability of populations depends upon metapopulation dynamics: the combination of reproduction and mortality within populations, as well as dispersal between populations. This study focuses on an Indo‐Pacific bottlenose dolphin (Tursiops aduncus) population in coastal waters near Bunbury, Western Australia. Demographic modeling...
Effective management of wildlife populations rely on knowledge of their abundance, survival, and reproductive rates. Maintaining long-term studies capable of estimating demographic parameters for long-lived, slow-reproducing species is challenging. Insights into the effects of research intensity on the statistical power to estimate demographic para...
This book addresses the issue of animal welfare within the tourism experience. Part I of the book provides a conceptual and historical foundation upon which to analyse animal welfare and the position of animals in tourism, and how these two issues intersect. Part II consists of 14 opinion pieces that discuss various issues associated with animal we...
The cost of reproduction is a key parameter determining a species' life history strategy. Despite exhibiting some of the fastest offspring growth rates among mammals, the cost of reproduction in baleen whales is largely unknown since standard field metabolic techniques cannot be applied. We quantified the cost of reproduction for southern right wha...
Microplastic pollution can impact filter-feeding marine megafauna, namely mobulid rays, filter-feeding sharks, and baleen whales. Emerging research on these flagship species highlights potential exposure to microplastic contamination and plastic-associated toxins. Research and its wide communication are needed to understand the magnitude of the iss...
Microsatellite genotype data and mitochondrial DNA haoplotypes.
In threatened wildlife populations, it is important to determine whether observed low genetic diversity may be due to recent anthropogenic pressure or the consequence of historic events. Historical size of the Irrawaddy dolphin (Orcaella brevirostris) population inhabiting the Mekong River is unknown and there is significant concern for long-term s...
Permission to publish Fig 1 under a CC BY license.
(XLSX)
We present results from the first broad scale distribution models for coastal dolphins - Australian humpback (Sousa sahulensis), Australian snubfin (Orcaella heinsohnii) and Indo-Pacific bottlenose (Tursiops aduncus) - in northern Western Australia (WA).
Large-scale climate modes such as El Niño Southern Oscillation (ENSO) influence population dynamics in many species, including marine top predators. However, few quantitative studies have investigated the influence of large-scale variability on resident marine top predator populations. We examined the effect of climate variability on the abundance...
Predation risk has a profound influence on the behavior of marine mammals, affecting grouping patterns and habitat use. Dolphins frequently bear evidence of shark bites, which can provide an indirect measure of predation pressure. Using photo-identification data, we investigated the prevalence of shark bites on three sympatric
species of inshore do...
The soundscapes of four bays along the Kona Coast of Hawaii Island were monitored between January 2011 and March 2013. Equivalent, unweighted sound pressure levels within standard 1/3rd-octave bands (dB re: 1 μPa) were calculated for each recording. Sound levels increased at night and were lowest during the daytime when spinner dolphins use the bay...
This final report for the Western Australian Marine Science Institution (WAMSI) documents the findings of a collaborative project aiming to increase our understanding of the distribution, abundance and population connectivity of Australian snubfin (Orcaella heinsohni) and humpback (Sousa sahulenis) dolphins, including the development of new researc...
Environmental impact assessments must be addressed at a scale that reflects the biological organization for the species affected. It can be challenging to identify the relevant local wildlife population for impact assessment for those species that are continuously distributed and highly mobile. Here, we document the existence of local communities o...
The analysis of apex predator diet has the ability to deliver valuable insights into ecosystem health, and the potential impacts a predator might have on commercially relevant species. The Australian sea lion (Neophoca cinerea) is an endemic apex predator and one of the world’s most endangered pinnipeds. Given that prey availability is vital to the...
Summary
1. The migration of humpback whales to and from their breeding grounds results in a short,
critical time period during which neonatal calves must acquire sufficient energy via suckling
from their fasting mothers to survive the long return journey.
2. Understanding neonate suckling behaviour is critical for understanding the energetics and
e...