FIGURE 1 - available via license: Creative Commons Attribution-NonCommercial 4.0 International
Content may be subject to copyright.
Map of the study region in the Northern Channel Islands, California (USA) (shading, binned number of Partnership for Interdisciplinary Studies of Coastal Oceans [PISCO] sampling events over the study period)
Source publication
Marine protected areas (MPAs) cover 3-7% of the world's ocean, and international organizations call for 30% coverage by 2030. Although numerous studies show that MPAs produce conservation benefits inside their borders, many MPAs are also justified on the grounds that they confer conservation benefits to the connected populations that span beyond th...
Context in source publication
Context 1
... used kelp forest survey data from the PISCO surveys in the Channel Islands in the DiD analyses. Divers from PISCO conducted visual scuba surveys at a large number of rocky reef and kelp forest sites inside and outside MPAs throughout the Channel Islands to produce estimates of densities of fishes that are both targeted and nontargeted by fishers (Figures 1 and 2). The details of the monitoring program are described in Caselle et al. (2015). ...
Citations
... Fishing closures have gained momentum over the last decades given their potential for promoting sustainable fisheries exploitation while also serving as conservation areas for marine habitats, other species and certain life stages of targeted species (e.g., Halpern, Warner, 2002;Bailey et al., 2010;Gaines et al., 2010;Watson et al., 2014;Cabral et al., 2020;Ovando et al., 2021). The closures can be broadly classified according to their duration (seasonal or permanent), size (large vs small) and the level of fishing restriction (no-take or partial-take). ...
... Despite the appealing concept of fishing closures among management and conservation practitioners, several studies have reported that their actual effectiveness remains difficult to quantify partially because of the challenge to conduct and replicate field experiments, and its timeconsuming nature to evaluate long-term biological responses to the closure (e.g., Moland et al., 2013;Bigné et al., 2019;Eero et al., 2019). The lack of empirical evidence has consequently promoted the development of a wide array of mechanistic models, which aim to evaluate the potential benefits of management actions such fishing closures (Grüss et al., 2014;Ovando et al., 2021). Many of these models focus on the benefits of biological and ecological components, while typically ignore the sociological and economic consequences (e.g., Nielsen et al., 2018). ...
The management of the western Baltic cod relies on a combination of regulation tools, including a seasonal spawning fishing closure. The complex population dynamics of the stock have nevertheless been posing considerable challenges to design closures, and the actual benefits of the seasonal spawning closure are still unclear. Often, only biological indicators have been used to evaluate the effectiveness of the closure, without considering socioeconomic effects on the fishery. In this study, we applied a Species Distribution Model (SDM) integrating commercial fishery and research survey data on a 15-year time series to design multiple alternative spatial closures, all based on identifying persistent essential fish habitats (i.e., nursery, spawning, and feeding grounds). We further used the spatial-explicit Management Strategy Evaluation (MSE) tool DISPLACE to contrast the outcomes of these fishing closures, and identify which provided the optimal balance between socioeconomic and biological demands and sustainability. Our results indicated that all closures benefitted the fisheries and stock. Although fishermen redirected their fishing effort to some extent to other stocks, increased profits were largely driven by increased cod catches as a consequence of reconstructed stock structure and enhanced spawning biomass. We conclude that the benefits of the closures are more linked to their size, than their actual purpose (i.e., protecting nursery, spawning, or feeding grounds).
... This illustrates the need to develop a suite of indices before implementing spatial fisheries-restrictions. Understanding where fishing would increase after such an intervention, and how that affects the total mortality rates from fishing, is one of the main challenges in designing protected areas successfully (Hilborn et al., 2004;Ovando et al., 2021). While our study provides novel insights into the spatial overlap between chondrichthyan distribution and bottom trawl fishing in the western part of the Adriatic Sea, there are certain limitations that should be considered when interpreting the results. ...
Sharks, rays, and chimaeras (chondrichthyans) play a crucial role in marine ecosystem functioning but are highly vulnerable to fishing. Hence, understanding the spatial overlap between chondrichthyans and fishing effort is essential for effective conservation and management. Here, we propose an integrated approach that combines Vessel Monitoring System data with geostatistical species distribution models to assess the potential impact of fishing on chondrichthyan populations in the western Adriatic Sea. By mapping the overlap between model-based chondrichthyan distribution, species richness, and the proportion of threathened species with bottom trawl fishing activities, we identify areas at high risk for chondrichthyan bycatch. Our findings show that many of these species are at risk across a large part of their distribution within the study area. Notably, there is a substantial spatial overlap between regions where threatened chondrichthyans are found and species-rich areas with locations of intensive bottom trawl fishing in the northern and central offshore regions of the western Adriatic, emphasizing the vulnerability of these species to fishing pressure. Furthermore, differences in overlap between distinct fishing gears highlight the importance of considering specific fishing practices when formulating management strategies. While our work provides novel insights to potential bycatch hotspots, limitations related to data sources, spatial resolution, and the inability to directly quantify fishing impacts should be considered. Nonetheless, our findings contribute to the development of targeted conservation and spatial management measures, offering a general approach to study model-based spatial hotspots aimed at protecting and sustaining chondrichthyan populations in the heavily exploited Adriatic Sea.
... When possible, establish permanent marine reserves to allow full population recovery and maximum biomass export to adjacent areas Populations of focal species recover at different rates in marine reserves and adjacent areas in the California Bight. 78 Populations of some focal species, such as sea cucumber, are likely to recover within a decade, while others, such as abalone, will take over 40 years of protection ...
Article Integrating climate adaptation and transboundary management: Guidelines for designing climate-smart marine protected areas Graphical abstract Highlights d We provide 21 guidelines for designing climate-smart transboundary protected areas d Future climates could decrease connectivity by 50% and hinder species recovery d Climate-smart networks require protecting critical sites and climate refugia d Adapting to climate change requires transboundary coordination in shared ecoregions
... Our results implied further conflict potentials because more central anglers had more negative attitudes toward conservation action, specifically extending the scope of protected areas. Fishery conservation conflicts around conservation areas are widespread and common around the world (Hilborn, 2007;Ovando et al., 2021), and are also reported from Rügen involving protected areas, cormorant protection, and to a lower extent, seal protection (Vogt, 2020). Current conservation efforts to protect cormorants and grey seal populations were found to be less accepted, with more central anglers agreeing to reduce the cormorant population and more behaviorally committed anglers to reduce grey seal stocks. ...
Understanding the attitudes of recreational anglers towards regulations and other stakeholders is important to inform fisheries management actions. We investigated the relationship of salient angler characteristics, specifically , specialization, catch orientation, place attachment and demographics, and the attitudes and beliefs regarding conservation and management of the northern pike (Esox lucius) stock inhabiting the lagoon ecosystems around the island of Rügen, Germany, in the southern Baltic Sea. The stock is currently in decline and stakeholder conflicts have escalated. Human dimensions data were gathered in an online survey where 1.965 anglers generated complete answers. Angler specialization (specifically behavioural and psychological commitment), selected catch orientations (release orientation and catch something construct), place attachment, and demographics (particularly age, residency, and education) were consistent correlates of attitudes toward management and conservation of northern pike. Anglers with a strong release orientation were more likely to express positive attitudes to their own harvest constraints, while more committed anglers held more negative beliefs about the behaviour of commercial fisheries, anglers, and conservation activity. Addressing local angler-fisher-conservation conflicts currently present in the Rügen pike fishery can best be achieved by targeting the more specialized, release-oriented, old, highly place-attached angler segments because these angler types have the highest degree of conflict sensitivity with other user groups and with conservation while at the same time accepting regulations more that minimize the impacts of fishing and angling on the fishery resource.
... Benefits for conservation and restoration are therefore well established, especially for relatively localized populations (Knutsen et al., 2022) or demographic structure and life-history traits (Dimarchopoulou et al., 2018;Sørdalen et al., 2022), whereas effects of MPAs diminish with higher mobility of species (Hilborn et al., 2004). Additionally, spillover effects from protected areas are often difficult to quantify (Di Lorenzo et al., 2016;Ovando et al., 2021). Because MPAs have often been designed around protecting specific species or habitats, they may have unforeseen consequences for other ecosystem components by altering species composition and food availability. ...
The spatial complexity of coastal ecosystems represents a challenge for the management of inshore resources. Here we compared two large fjord systems in northern Norway that have been closed for all bottom trawling for 50 years to a fjord with continuous shrimp fishery with bottom trawls. No significant differences were found between fjords with and without commercial trawling in population density and stock composition of northern shrimp (Pandalus borealis) and their main predator, Atlantic cod (Gadus morhua). Shrimp density was instead linked with bottom depth, while shrimp size and stage composition as well as cod density were explained by seasonal effects and shrimp density. For shrimp, a large degree of the observed variation was captured by spatial correlation that could not be explained by other covariates. The results underline the complex ecology in heavily structured coastal habitats and indicate that coastal shrimp dynamics are shaped by an interplay of multiple ecological and environmental drivers, possibly in concert with local genetic adaptations. The substantial fine-scale spatial variation adds to the challenges of assessing and managing fisheries resources in these fjord ecosystems. Because shrimp are an important forage species, notably as prey for cod, there are potential management conflicts between rebuilding cod stocks and reopening closed shrimp trawling areas.
... Other common MPA survey techniques such as hook and line, trapping or other fishery dependent methods tend to capture only or primarily fished species while SCUBA and camera-based methods are less species specific. Non-targeted species act as a control for measuring the potential impacts of MPAs on targeted species where spatial and environmental controls are unavailable (Tetreault and Ambrose 2007, Caselle et al. 2015, Carr et al 2021, Ovando et al. 2021. The ability to observe non-targeted species provides important context for researchers when comparing the results of targeted fish species, since we do not expect the same impact of protection on unfished species. ...
... Such information would improve our understanding of how MPAs affect a relatively abundant non-targeted species, inform the use of non-targeted species as a control, and contribute to a growing body of literature detailing species interactions in MPAs (Micheli et al. 2004, Guidetti 2006, Watson et al. 2007, Caselle et al. 2015, Ovando et al. 2021, Kraufvelin et al. 2023. ...
Marine Protected Areas (MPAs) have been implemented worldwide as a tool for
improving the overall health and function of fisheries and marine ecosystems impacted by fishing activity. Monitoring the performance of MPAs in a comprehensive way is crucial for the effective management and thoughtful implementation of new MPAs. In California, mesophotic (30-100m) rocky reef fish communities are a valuable commercial/recreational resource, though the effects of MPAs on this community remain relatively understudied. This is at least partially a result of depth restricted sampling tools that do not typically overlap; SCUBA surveys are generally limited to shallow depths (<30 m) and Remotely Operated
Vehicle/Autonomous Underwater Vehicle surveys are often used for deep water (>100m). Additionally, traditional extractive techniques like trawl surveys are limited by their inability to effectively sample high relief rocky habitats, and are not commonly used in MPAs due to their destructive nature. With this study we tested the effects of two MPAs on demersal fish communities living on mesophotic rocky reefs utilizing Baited Remove Underwater Video (BRUV) surveys. We deployed BRUV landers annually from 2019 to 2021 at Anacapa State Marine Reserve/State Marine Conservation Area (SMR/SMCA) and Carrington Pt. SMR. We observed significant positive reserve effects on the total biomass of targeted (i.e., fished) species and on the size structure of individual focal species at both study sites. Relative abundance (MaxN) proved to be a less sensitive metric than biomass for detecting MPA effects, underscoring the utility of a stereo-video camera system that is capable of capturing highly accurate fish measurements. Dissimilar rocky habitat abundance for the deepest depth zones at Anacapa Island, where rockfishes (Sebastes spp.) represent the largest proportion of the fish community, is likely one explanation for the negative reserve effect we observed for targeted rockfish abundance at this site. The results of this study provide useful information on how two California MPAs affect valuable fish communities that have historically been understudied and emphasize the importance of accurate fish measurement to detect these effects. This work also highlights the significance of habitat availability on the distribution of species with high habitat affinity. The continued monitoring of demersal fish communities on mesophotic rocky reefs would provide resource managers a more comprehensive understanding of MPA performance in California.
... The evidence for beneficial effects outside MPAs, especially beyond the immediate "halo" where spillover is usually detected, is less certain that the evidence for change within MPAs. Even where good data exist, e.g. in California there is good evidence of local spillover of lobsters [26] but not for changes to wider fish populations [28]. In contrast, studies in New Zealand found that marine reserves made major contributions to wider snapper populations [29]. ...
... Such effects can lead to spillover of adult fish biomass in waters up to 2 km away, sometimes increasing fisheries yield ). While, in some cases, reserves have proven useful for promoting and protecting biomass ), improper implementation has led to little to no impact (Halpern 2003). Indeed, marine reserve performance both inside and outside of protected areas is not always clear (Hilborn et al. 2004;Ovando et al. 2021) and other socioecological variables are needed to maximize the benefits of marine reserves (Edgar et al. 2014;Grorud-Colvert et al. 2021). Moreover, as climate change shifts the distribution of marine species worldwide, questions remain regarding the impacts of such shifts to the effectiveness of marine reserves (Bruno et al. 2018;IPBES 2019;Jacquemont et al. 2022). ...
... It is important to mention that the objective (and design) of this study was not to test the plausibility of protected waters supplying biomass to surrounding waters (i.e., spillover effect). We acknowledge that in the real world, spillover effect is case specific (Hilborn and Sinclair 2021;Ovando et al. 2021) and, when reported, often smaller (in terms of spatial scale) than our grid ). While our hypothetical world assumes spillover effect happens in all reserves (as a mechanistic part of the DBEM), we limit this effect to only the surrounding grid cells of a protected cell. ...
... Our model supports this theory resulting in less losses in biomass in waters directly surrounding marine reserves in comparison to when no marine reserve is implemented, under future climate change scenarios. However, the spillover effect continues to be a source of contention as recent studies have noted that protected areas provide benefits to biomass within their borders, but that their contributions to local and regional population-wide effects are less evident (Ovando et al. 2021). ...
The world has set ambitious goals to protect marine biodiversity and improve ocean health in the face of anthropogenic threats. Yet, the efficiency of spatial tools such as marine reserves to protect biodiversity is threatened as climate change shifts species distributions globally. Here, we investigate the ability of global marine reserves to protect fish biomass under future climate change scenarios. Moreover, we explore regional patterns and compare worlds with and without marine reserves. We rely on computer modeling to simulate an utopian world where all marine reserves thrive and ocean governance is effective. Results suggest that climate change will affect fish biomass in most marine reserves and their surrounding waters throughout the 21st century. The biomass change varies among regions, with tropical reserves losing biomass, temperate ones gaining, and polar reserves having mixed effects. Overall, a world with marine reserves will still be better off in terms of fish biomass than a world without marine reserves. Our study highlights the need to promote climate resilient conservation methods if we are to maintain and recover biodiversity in the ocean under a changing world.
... This is because a net benefit to fisheries stemming from no-take protected areas can only be expected if the catch of fish is increased outside the boundaries of protected areas relative to the situation before the implementation of the measure (Hilborn et al., 2004;Moland et al., 2013). There is abundant evidence that lasting spill-over effects of protected areas are either not present or difficult to detect because the fishing effort saved from protected areas is typically displayed beyond the protected area boundaries or because of ecological constraints preventing significant spill-over by species of relevance to fisheries (Fletcher et al., 2015;Hilborn and Sinclair, 2021;Ovando et al., 2021). The implementation of protected areas, especially marine protected areas, and their effectiveness continues to be controversial, specifically in commercial marine fisheries where often a central authority is the decision-maker (Edgar et al., 2007;Jameson et al., 2002;Sale et al., 2005). ...
Protected areas are a common management tool to conserve habitats and species by controlling access and disturbances by humans. Whenever protected areas result in restricting access to riparian zones in lakes, they may have positive effects on habitats and taxa beyond fish by lowering influences of trampling or boating on plants, by reducing the degree of human-induced disturbances to sensitive taxa such as birds, and by reducing fishing effort. However, especially in small freshwater systems knowledge about the functioning of protected areas that cover only parts of the lake shorelines is limited. We studied small gravel pit lakes in Germany where recreational fishing clubs have voluntarily assigned no-access riparian protected areas on parts of the lake shorelines and examined outcomes for habitat quality, plants, fish and bird populations. A total of 15 lakes were sampled, and we assessed habitat structure and abundance of plants, and fish within and outside protected areas and bird abundance at the lake scale, relying on standardized sampling methods. After controlling for confounding environmental factors related to lake morphology, age, nutrients, and land use, we detected positive contributions of small-scale riparian protected areas on habitat structure, riparian vegetation, local fish abundance and abundance of sensitive songbirds at the lake-scale, but we found no effects on aquatic vegetation and on disturbance-sensitive waterfowl species. Scale-restricted riparian protected areas voluntarily assigned by recreational fishing clubs can have positive outcomes for habitat quality and biodiversity, particularly by reducing trampling and access to anglers and other recreationists. Moreover, through provision of key habitat for young fish, small-scale riparian protected areas can also benefit fish abundance and in turn recreational fisheries.
... Conservation method 1: MPAs, fisheries closures, and habitat restoration Marine protected areas (MPAs) typically provide ecosystemlevel protection across various species, which may include cephalopods, while fisheries closures tend to be more targeted approaches to reduce population declines or protect species (Ovando et al., 2021), life stages or habitats from fishing activities (e.g. nursery areas or spawning aggregations) (Roberts et al., 2005). ...
Cuttlefish are an important global fisheries resource, and their demand is placing increasing pressure on populations in many areas, necessitating conservation measures. We reviewed evidence from case studies spanning Europe, Africa, Asia, and Australia encompassing diverse intervention methods (fisheries closures, protected areas, habitat restoration, fishing-gear modifications, promoting egg survival, and restocking), and we also discuss the effects of pollution on cuttlefish. We conclude: (1) spatio-temporal closures need to encompass substantial portions of a species’ range and protect at least one major part of their life cycle; (2) fishing-gear modifications have the potential to reduce unwanted cuttlefish capture, but more comprehensive trials are needed; (3) egg survival can be improved by diverting and salvaging from traps; (4) existing lab rearing and restocking may not produce financially viable results; and (5) fisheries management policies should be regularly reviewed in light of rapid changes in cuttlefish stock status. Further, citizen science can provide data to reduce uncertainty in empirical assessments. The information synthesized in this review will guide managers and stakeholders to implement regulations and conservation initiatives that increase the productivity and sustainability of fisheries interacting with cuttlefish, and highlights gaps in knowledge that need to be addressed.
