News

CSI: Sharks

Published on December 9, 2009

DNA tracing may be a way to fight the sharkfin soup threat to that endangered species.

The practice of “finning” – cutting off the fins of sharks to meet a dramatically growing Asian demand, then often throwing the fish back into the water, where it sinks to the bottom, unable to move and therefore to feed – is constituting a severe threat to shark populations on the brink to extinction.
DNA testing can now make it possible to trace shark fins on sale back to the region where the fish originated.

According to the journal Endangered Species Research, researchers used a method called “genetic stock identification” to test samples of 62 scalloped hammerhead shark fins—an endangered species—from the Hong Kong fin market. They analyzed the mitochondrial DNA, which is passed down from the mother and is traceable to the sharks’ birth waters, and found that 57 of those sharks came from Atlantic and Indo-Pacific waters, while 21 percent live in the western Atlantic, where sharks’ numbers have now collapsed. The results were published online in Endangered Species Research.