Putting sharks on the map: A global standard for improving shark area-based conservation

Abstract

Area-based conservation is essential to safeguard declining biodiversity. Several approaches have been developed for identifying networks of globally important areas based on the delineation of sites or seascapes of importance for various elements of biodiversity (e.g., birds, marine mammals). Sharks, rays, and chimaeras are facing a biodiversity crisis with an estimated 37% of species threatened with extinction driven by overfishing. Yet spatial planning tools often fail to consider the habitat needs critical for their survival. The Important Shark and Ray Area (ISRA) approach is proposed as a response to the dire global status of sharks, rays, and chimaeras. A set of four globally standardized scientific criteria, with seven sub-criteria, was developed based on input collated during four shark, biodiversity, and policy expert workshops conducted in 2022. The ISRA Criteria provide a framework to identify discrete, three-dimensional portions of habitat important for one or more shark, ray, or chimaera species, that have the potential to be delineated and managed for conservation. The ISRA Criteria can be applied to all environments where sharks occur (marine, estuarine, and freshwater) and consider the diversity of species, their complex behaviors and ecology, and biological needs. The identification of ISRAs will guide the development, design, and application of area-based conservation initiatives for sharks, rays, and chimaeras, and contribute to their recovery.

Global hotspots of shark interactions with industrial longline fisheries

“…The patterns of risk we identify are largely driven by the catch of blue sharks, which represent ~78% of all shark catch reported by tRFMOs globally between 2012-2020 (Supplementary Material, Table S9). These catch risk hotspots can be compared to biologically important areas for blue sharks and other shark species (e.g., Hyde et al, 2022). For example, catch risk hotspots identified off the coast of Southwest Africa occur in a known potential blue shark nursery habitat off the coast of Namibia where a high catch density of immature sharks have been recorded by onboard observers (Coelho et al, 2018).…”

“…Although our results primarily represent a few commonly reported species, pelagic longlines have the potential to interact with numerous shark species (n = 15 unique species and 5 higher order classifications are included here) with highly variable life histories and movement capacities, which can present challenges for designing effective spatial management to rebuild overexploited populations. Further work is needed to identify where shark catch risk hotspots align with ecologically important areas, such as aggregation sites and migration corridors, to ensure area-based protection and management are effective for intended species (Boerder et al, 2019;Gilman et al, 2019;Hyde et al, 2022). Behavioral considerations, including philopatry and movement capacity, will further determine which shark populations are most likely to respond to spatial management measures (Boerder et al, 2019), and future efforts will need to examine the seasonality and persistence of catch risk hotspots to determine whether static or dynamic management is preferred.…”

Manta and devil ray aggregations: conservation challenges and developments in the field

“…Fishing bans of mobulids should also be considered throughout their range, while identifying mobulid aggregations at specific times and locations can offer important management and conservation opportunities (Clark et al, 2014) such as the designation of spatial protection areas. Such an approach is being included in the identification of Important Shark and Ray Areas (ISRAs) for mobulids (Hyde et al, 2022). Furthermore, socio-economic surveys among fishermen communities and associated stakeholders should also be implemented to understand the economic and social impacts that can arise from such management designations (e.g., Peru; Guirkinger et al, 2021 and Indonesia;Booth et al, 2020;Booth et al, 2021).…”

“…Spatial protection, particularly if based on ISRAs, can play an important role in protecting populations from anthropogenic impacts at aggregation sites (Germanov et al, 2019;Murray et al, 2020;Setyawan et al, 2022b). ISRAs provide refereed, actionable information on sites that are critical to mobulid survival, such as aggregations (Hyde et al, 2022). While it is likely not feasible to protect the entire home ranges of most mobulid species, aggregation sites for mobulids may encompass important areas for critical life history stages (Marshall and Bennett, 2010a;Stevens, 2016;Germanov et al, 2019;Setyawan et al, 2022b).…”

Chondrichthyan fauna from the Marine Protected Area Namuncurá at Burdwood Bank: exploring egg nursery grounds

“…In Argentinean waters, known egg-laying and nursery areas within MPAs are under legislation that allows for shing activities. In this regard, this study becomes relevant because it shows that the MPAs located at the BB allow protection of egg-laying grounds, critical areas for chondrichthyans´ survival according to The Important Shark and Ray Area (ISRA) approach, that provides a framework to identify areas of interest for the conservation of chondrichthyans based on different criteria, such as the presence of reproductive areas (sub-criteria C1) (Hyde et al 2022). These results show the importance of the MPAs located at BB for the conservation of several species of oviparous chondrichthyans in southern waters of the South West Atlantic.…”