Fisheries authorities frequently ask the Australian Museum DNA Laboratory to provide forensic identification of illegally taken shark fins, says Museum geneticist Dr Rebecca Johnson.
It is estimated that upwards of 70 million sharks are killed worldwide annually – mainly to meet the burgeoning demand for their fins. The demand for shark fins means that up to 95% of the total weight of a shark can be discarded. With the fins removed, the torso is often discarded to the sea (also known as ‘finning’), often while the shark is still alive.
In this the International Year of Biodiversity it is worth spending at least a few minutes considering the important and diverse role sharks play in the biodiversity of our marine environment.Sharks are a highly diverse group of animals with important roles in marine ecosystems, from scavengers to top predators, and according to the International Union for Conservation of Nature, many species are considered vulnerable or threatened , mainly from overfishing.
Typically sharks have a relatively low rate of reproduction and small populations. Certain species are targeted in numerous fisheries, and they also are snagged as by-catch.
A number of countries have introduced legislation to prevent shark-finning. Some stipulate that fins must constitute 5 per cent of the total weight of shark carcasses onboard. Australia is one of the few countries that require captured sharks must arrive in port intact, with fins still attached.
Without the carcass, it can be difficult to distinguish legal fishery species from protected species. Fins held without the rest of the carcass are illegal in Australia and can be seized by fisheries officers if detected.
Fisheries authorities may also want to know which species have been taken, as additional penalties apply for taking protected species. They frequently ask the Australian Museum DNA Laboratory to identify illegally taken shark fins.
Using DNA techniques we have identified fins from a vast number of Australian shark species, including those listed as vulnerable or near threatened. DNA identification was used in a recently prosecuted case involving seizure of illegally held fins on a Commonwealth vessel. This single seizure in 2006 represented no fewer than 22 individual sharks.
In this case the defendants were convicted and collectively fined more than $23,000 – one of the larger penalties for illegal trafficking of wildlife that will hopefully act as a deterrent to others.
Johnson, RN (in press). The use of DNA identification in prosecuting wildlife-traffickers in Australia. Do the penalties fit the crimes? Forensic Science, Medicine & Pathology.