Tags: Hai-Forschung 

Studying Sharks

In shark conservation, the terms “data deficient” and “lack of data” are prevalent when referring to some of the most basic facts about most species of sharks, like lifespan or litter size. This can cause detrimental delays in ensuring protections for sharks. Historically, sharks were not considered commercially important species so the very few who researched sharks focused on mitigating shark and human interactions or the academic pursuit of general biological knowledge. Shark research has definitely expanded in recent times but there are still glaring gaps of knowledge.

Shark Tagging

A casey tag inserted into a bull shark for tag and recapture study.

Shark research is being conducted all over the world to address these gaps, investigating shark species biology, life history, ecology, population, and movements, monitoring fisheries and landings. The diet of baby lemon sharks is investigated by inverting their stomachs, collecting and identifying what comes out. The stress of a Caribbean reef shark being caught on a hook is studied by drawing the blood and analyzing the hormones. Acoustic tags are surgically implanted into bull sharks to see when they enter fresh water systems. Tiny bits of dorsal fins are clipped and sent to labs for genetic analysis to see what sharks are related to each other. Other bits of fin clips are analyzed for isotopes to determine a species trophic level. Some muscle tissue is studied for levels of contaminants. Observers on commercial boats are recording shark catches and landings while recreational anglers volunteer to attach tags to sharks they release for population studies.

Much of this research is now being undertaken with the knowledge that sharks are a conservation priority. The more we know and understand about these animals, their biological vulnerability to fishing activities, their movements, how long they live, where they migrate, we can help preserve them.