Economics drive the extinction of large marine animals

June 10, 2016

Research conducted by Simon Fraser University (SFU) and Colby College in Maine, finds that large marine animals are at a greater risk of extinction as a result of their large body size and their value to luxury markets, including game hunters.

The report’s co-author, Loren McClenachan who completed post-doctoral work with co-authors Andrew Cooper and Nicholas Dulvy, both SFU professors, point out that “body size is a well-understood correlate of extinction risk as larger species tend to have the lowest population growth rates and hence are less able to replace individuals killed by hunting.” A double jeopardy situation occurs when luxury markets also value these same animals. Terrestrial animals in this category include rhinoceros and elephants while marine species at risk are sharks and rays, valued for their fins and gill plates.

The study identified over 100 large marine and terrestrial species targeted by international luxury markets. The authors estimated the value of each species and pinpointed the relationship between extinction risk, value and body size. When the price of the valued body part is spread over the entire carcass, the authors found that marine animals turned out to be as valuable as terrestrial animals. “Hunters don’t kill kilograms, they kill individuals, so we need to pay attention to these high values of individual animals,” explains McClenachan.

Protection of terrestrial animals is largely up to the countries that they inhabit, however, the scale of territory that marine species inhabit is vast, encompassing multiple international boundaries and making adoption of universal protective legislation problematic.

Dulvy is disturbed about the lack of priority around conservation efforts afforded to marine species. After consulting the lists of the species most at risk from extinction, he found that “Marine animals were lumped together at the bottom of the list, below medicinal plants, orchids and parrots. Sure all these plants and animals need protection too, but to lump marine things at the bottom means they inevitably get low priority.”

The authors suggest a strategy to mitigate extinction risks should include international trade regulation, national and regional protections and a reduction of consumer demand for unsustainable products.

“99% of livable space on earth is in the oceans—we need to do a much better job of tracking and managing international trade flows of high value marine products and eliminating illegal wildlife trade,” says Dulvy.