Back in June 2013, fisherman caught an enormous female shortfin mako shark off Huntington Beach, California. The small group of fisherman were filming for Outdoor Channel reality television show, ‘Jim Shockey’s The Professionals’. Many had wondered why the shark wasn’t simply released. After the film and photos were over, the animal was donated to a scientific research group, and their findings were just published in the July issue of the Journal of Fish Biology.
The study determined that there were very high levels of a number of contaminants in the shark. After analyzing the liver, DDT levels were found to be 100 times the legal limit of consumption allowed by the EPA. PCBs were over 250 times the legal limit. Mercury, 45 times the legal limit for women and children to eat it. Both PCBs (a substance used in the manufacturing of electronics) and DDT (a pesticide) were outlawed back in the 1970s because of their known toxicity. Unfortunately, so much of those chemicals made it into the water that they have accumulated in the seabed.
Larger predators, such as sharks, end up having higher levels of these toxins due to bioaccumulation. While the smaller fish end up having some of the chemicals present, the larger animals that continually eat these smaller fish end up having much higher levels as a result. In addition, some of the toxins are passed to their offspring, perpetuating the problem.
We often hear these trophy hunts disguised as providing large quantities of food for families, communities, even indigent populations. Hopefully, studies like this will help to educate the public and lead to more animals being released alive back into the wild. There’s simply no good reason to kill and land an impressive shark like this.