Thursday, August 7, 2008
The Science of Sharks
I spent the last two days dissecting sharks. Yes, that is right... I said dissecting. I performed eight personally and witnessed many, many more, including a great white dissection. What is a conservationist doing spending time with a bunch of dead sharks? Yes, I asked myself the same question.
But now I realize the important role this type of science plays in the conservation of sharks. How do we know what areas specifically we need to protect? What their role in the ecosystem is? What sustainable catch limits are based upon their growth and reproduction rates?
The point of the research is truly to understand animals that few people know anything about and study these animals that are not currently protected in the hopes of creating appropriate legislation in the future.
Our examinations included things like determining the size of the shark when it reaches sexual maturity (to define size restrictions in catch), identifying mercury levels in skin to identify environmental contaminants and set restraints for sharks caught primarily for fillet consumption, examining stomach contents to determine where the sharks dwell and areas that should be protected, looking at reproduction rates and health of the population to set catch limits, identifying isotropic levels to determine ecosystem dependencies, etc... All in the name of conservation.
None of the sharks were killed for this - all were killed as bycatch or by fisherman (including the white shark.)
I know it may seem hard to believe, but I learned more than I thought was possible. For the first time, I could see the gel in the Ampullae of Lorenzini and examine the shark’s lateral line. I understood reproduction, biological composition and about 100 other things I have read but never truly grasped. And while it broke my heart, at the same time, I realized the importance of science and the discovery of critical scientific data required for good conservation regulations. Things that sometimes require the study of dead animals...
And, as odd as this may sound as another benefit, I stink like a dead shark – a benefit as now I will be able to distinctively identify it in any fisherman wharf, processing plant or market and know if sharks have been caught illegally (a smell that you can NEVER forget).
I never thought I would say this, but I am a more informed, educated and powerful conservationist because I spent two days with dead sharks. Thanks to Charlene Da Silva with Marine Coastal Management here in South Africa and Alison Kock of Save Our Seas (and my fellow Shark Angel.) These two are some seriously amazing women, scientists and shark conservationists.
A bit about the sharks we dissected:
Mustelus mustelus (smoothhound shark) - IUCN status - not evaluated. important fisheries species in European, Mediterreanean, and west African waters. Used fresh, frozen, and smoked for food., liver for oil, and for fishmeal.
Mustelus palumbes (whitespot smoothhound shark) - IUCN status - not evaluated - insufficient data. Taken by sports anglers and as bycatch, but usually discarded.