SciCombinator

Discover the most talked about and latest scientific content & concepts.

G Roff, CJ Brown, MA Priest and PJ Mumby
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‚ÄČkm 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.
Tweets*
220
Facebook likes*
5
Reddit*
0
News coverage*
52
Blogs*
7
SC clicks
0
Concepts
-
MeSH headings
-
comments powered by Disqus

* Data courtesy of Altmetric.com