Smarter Sharks - Are They Wising Up To Our Tagging Techniques?

March 18, 2008

There is an interesting article on the Cardiff University website describing the offshoots of the research being conducted on lemon shark population trends by Steve Kessel, an Earth and Ocean Sciences PhD student at Cardiff.

Mr. Kessel has spent the past three years working at the world-renowned Bimini Biological Field Station, also known as Shark Lab, in the Bahamas studying population trends among lemon sharks and believes current research techniques may underestimate numbers - because sharks are getting wise to human methods of counting.

Mr. Kessel’s theory is that sharks (at least for the lemon shark population he is working with) appear to be catching on to human techniques for tagging them, and are learning how to avoid them.

Traditional methods of tagging sharks have involved putting bait on a long line, then implanting a transmitter once it bites. Steve Kessel is now using other techniques to tag sharks, including using skiffs to corral them into shallow water where they can be netted, and aerial surveys for abundance counts.

If this research proves to be accurate, it just illustrates how adaptable these creatures are and how they can adjust to subtle changes in their environment.

As I read the article, I was wondering how to quantify this type of research as it seems far more qualitative than quantitative. Mr. Kessel’s perspective on shark tagging and the shark’s recognition of tagging techniques were excellent observations from his ongoing research. His theory raises interesting questions about how sharks recognize what is going on in their surrounding environment.

You can read the complete article, and see an accompanying video, at the Cardiff University website.