Dataset Information

Decline of coastal apex shark populations over the past half century.

ABSTRACT: Overexploitation of large apex marine predators is widespread in the world's oceans, yet the timing and extent of declines are poorly understood. Here we reconstruct a unique fisheries-independent dataset from a shark control programme spanning 1760?km of the Australian coastline over the past 55 years. We report substantial declines (74-92%) of catch per unit effort of hammerhead (Sphyrnidae), whaler (Carcharhinidae), tiger shark (Galeocerdo cuvier) and white sharks (Carcharodon carcharias). Following onset of the program in the 1960s, catch rates in new installations in subsequent decades occurred at a substantially lower rate, indicating regional depletion of shark populations over the past half a century. Concurrent declines in body size and the probability of encountering mature individuals suggests that apex shark populations are more vulnerable to exploitation than previously thought. Ongoing declines and lack of recovery of vulnerable and protected shark species are a cause for concern.

SUBMITTER: Roff G

PROVIDER: S-EPMC6292889 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Decline of coastal apex shark populations over the past half century.

Roff George G Brown Christopher J CJ Priest Mark A MA Mumby Peter J PJ

Communications biology 20181213

Overexploitation of large apex marine predators is widespread in the world's oceans, yet the timing and extent of declines are poorly understood. Here we reconstruct a unique fisheries-independent dataset from a shark control programme spanning 1760 km of the Australian coastline over the past 55 years. We report substantial declines (74-92%) of catch per unit effort of hammerhead (Sphyrnidae), whaler (Carcharhinidae), tiger shark (<i>Galeocerdo cuvier</i>) and white sharks (<i>Carcharodon carch ...[more]

PMID: 30564744

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Dataset Information

Decline of coastal apex shark populations over the past half century.

Publications

Decline of coastal apex shark populations over the past half century.

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