Sizing up the ecological role of sharks as predators

Heupel, Michelle R.; Knip, Danielle M.; Simpfendorfer, Colin A.; Dulvy, Nicholas K.

doi:10.3354/meps10597

Cited by 222 publications

(151 citation statements)

References 65 publications

Supporting

Mentioning

147

Contrasting

Unclassified

Order By: Relevance

“…There are a number or marine parks with no-fishing zones within the range of movements observed here, including the GBR Marine Park, the Great Sandy Marine Park, and the Moreton Bay Marine Park. While these parks offer some protection, the scale of C. leucas movements relative to the size of no-fishing areas suggest limited conservation benefits and hence additional management measures that are already in place, including catch limits and a maximum size limit of 1.5 m, are likely justified (Heupel et al, 2014). Regular movement across state boundaries highlights the need for cooperation between jurisdictions to ensure sharks receive sufficient protection throughout their migrations.…”

Section: Discussionmentioning

confidence: 99%

“…Management and conservation issues are critically important for species that move long distances, play a key ecological role in habitats, and are unlikely to benefit from spatial or regional management measures due to their movement patterns (Heupel et al, 2014). Species that move over long distances are also more likely to move between different jurisdictions, further complicating management and/or conservation efforts.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Conservation challenges of sharks with continental scale migrations

et al. 2015

View full text Add to dashboard Cite

Understanding movement and connectivity of populations is increasingly important as human and climate change pressures become more pervasive, but can be problematic in difficult to observe species such as large marine predators. We examined the movements of bull sharks, Carcharhinus leucas, using acoustic telemetry arrays along the east coast of Australia. Approximately half of 75 individuals released in temperate waters moved into tropical reef regions, with both sexes undertaking long-range movements and multiple individuals making return trips. Only 3% of 39 individuals released in tropical reef habitats moved south to temperate waters, but approximately 25% moved to southern reef or subtropical coastal areas. These results reveal complex linkages along the east coast of Australia which suggest a tropical reef based population comprised of individuals that migrate to multiple regions. Connectivity between locations along the east coast of Australia creates important conservation challenges for resource managers in multiple jurisdictions.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Conservation challenges of sharks with continental scale migrations

et al. 2015

View full text Add to dashboard Cite

show abstract

“…(8) Predators that are known to exhibit diffuse predation, although their effect on lower trophic levels is still poorly understood (Heupel et al, 2014). (9) Cryptic, invertebrate, and nocturnal organisms which are often ignored in food webs (Marnane and Bellwood, 2002;Kolasinski et al, 2016).…”

Section: The Contributions Of Trophodynamics To Coral Reef Ecologymentioning

confidence: 99%

“…Documented declines in top predators and keystone species from anthropogenic disturbance (Dulvy et al, 2004;Sandin et al, 2008;Estes et al, 2011) have resulted in exploration of trophic cascades and assessment of ecological roles of predators in coral reef reefs (Heupel et al, 2014;Boaden and Kingsford, 2015;Rizzari et al, 2015;Weijerman et al, 2015;Thillainath et al, 2016). However, identifying trophic cascades is difficult in reef ecosystems.…”

Section: Introductionmentioning

confidence: 99%

Trophodynamics as a Tool for Understanding Coral Reef Ecosystems

et al. 2018

View full text Add to dashboard Cite

The increased frequency of publications concerning trophic ecology of coral reefs suggests a degree of interest in the role species and functional groups play in energy flow within these systems. Coral reef ecosystems are particularly complex, however, and assignment of trophic positions requires precise knowledge of mechanisms driving food webs and population dynamics. Competent analytical tools and empirical analysis are integral to defining ecosystem processes and avoiding misinterpretation of results. Here we examine the contribution of trophodynamics to informing ecological roles and understanding of coral reef ecology. Applied trophic studies of coral reefs were used to identify recent trends in methodology and analysis. Although research is increasing, clear definitions and scaling of studies is lacking. Trophodynamic studies will require more precise spatial and temporal data collection and analysis using multiple methods to fully explore the complex interactions within coral reef ecosystems.

show abstract

“…Elasmobranchs (sharks and rays) are a key group of marine predators, suspected to mediate trophic cascades as top or meso-predatory species (Myers et al, 2007;Baum and Worm, 2009;Heithaus et al, 2012). In recent years, these species have attracted increasing scientific concern due to the large declines in their population abundances (FAO, 1999;Baum and Myers, 2004;Ferretti et al, 2008Ferretti et al, , 2010) and a greater understanding of their ecological importance (Heupel et al, 2014) and high vulnerability to extinction risk (Camhi et al, 2008;García et al, 2008;Dulvy et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

Review of the Diversity, Ecology, and Conservation of Elasmobranchs in the Azores Region, Mid-North Atlantic

Das

Afonso

2017

Front. Mar. Sci.

View full text Add to dashboard Cite

A vulnerable species group, such as, the elasmobranchs, in a data-deficient context presents a complicated management problem. Evidence suggests that the Azores islands, a remote archipelago on the Mid-Atlantic Ridge, serve essential functions in the life-history of species across taxa. The diversity of marine resources within its EEZ are exploited by local to international fleets, and the full extent of fishing pressure can often be underestimated. Although sharks and rays appear to be of minor importance in the fishery, the possibilities of illegal, unreported, and unregulated fishing raises concerns about these threatened species. However, this group has failed to attract management attention, visible in the lack of regional studies focused on biodiversity, ecology, or threats of elasmobranchs. Our work attempts to review and update the information on elasmobranchs of the Azores and identify potential threats, mainly by the local fisheries. We aim to highlight knowledge gaps that require further research and conservation actions. We (1) update the annotated checklist of elasmobranch species, (2) compare species distribution across a biogeographically similar section of the North Atlantic, and (3) analyze the interaction of elasmobranch species with local fisheries. We confirm 61 chondrichthyan species for the Azores (39 sharks, 17 rays, and 5 chimaeras), adding 19 species to the previous annotated checklist of 1997. The Azores elasmobranch species assemblage most resembles Madeira, the neighboring Macaronesian archipelago. Biogeographic affinities between the chosen regions of the North Atlantic are reflected in the taxonomic structure of families. Although underestimated in the local fisheries, elasmobranchs constitute a regular but highly variable portion of total landings. Misreporting and misidentification is perhaps the greatest concern in the local fisheries records, further aggravated by few existing catch regulations for elasmobranchs. Local knowledge indicates that the Azores serves as essential habitat for at least a few species in coastal areas and shallow seamounts, and potentially so for a number of deep-sea elasmobranchs. The intersection of fishery threats and local essential habitat functions around the archipelago warrants greater research effort and studies.

show abstract

Sizing up the ecological role of sharks as predators

Cited by 222 publications

References 65 publications

Conservation challenges of sharks with continental scale migrations

Conservation challenges of sharks with continental scale migrations

Trophodynamics as a Tool for Understanding Coral Reef Ecosystems

Review of the Diversity, Ecology, and Conservation of Elasmobranchs in the Azores Region, Mid-North Atlantic

Contact Info

Product

Resources

About