Every aspect of our data gathering process is designed to minimize harm to animals (our research subjects). We use special fishing and tagging gear intended to reduce stress and promote shark safety. Please explore the Animal Welfare section of the website to learn more about the protocols our team follows to promote shark welfare.
The Shark Research & Conservation Program uses special fishing units called drumlines (composed of a single weight and attached hook & line) that promotes shark vitality when fishing for sharks. The gear permits species which are ram ventilaters (need to keep moving to breathe) to swim in big circles around the weight when caught. The ability to swim relatively freely can also minimize stress-related C02 and lactic acid buildup in shark muscle.
Circle hooks can help reduce negative outcomes for captured sharks over other hook types, most notably J-hooks. Circle hooks are designed to catch in the shark’s jaw, instead of catching on the shark’s stomach or gills, which can otherwise cause injury. The hooks can also more easily be removed from the jaw, leaving a very superficial wound that heals quickly. Circle hooks help us selectively target sharks, reducing unwanted bycatch of other species. We recommend circle hooks not only for research-related capture, but for recreational fishermen practicing catch-and-release fishing who want to improve animal welfare.
Captured sharks are brought onto a specialized platform on the back of our research vessel, where a saltwater pump is immediately placed in the sharks’ mouth. This allows oxygenated water to flow over its gills throughout the shark’s brief work-up. During data collection, sharks have a small muscle biopsy taken (recaptured sharks demonstrate that the biopsy site is completely healed within just a few weeks), are tagged with a spaghetti tag in their dorsal fin (where they have few nerve endings and blood vessels), have blood drawn, are measured, have a small clip of their fin cartilage taken, and are released.
Historically, the traditional method for gathering the types of data we collect was to kill animals. Although capture may still be a stressful process for sharks, our research focuses on minimizing shark stress and promoting survival. Our research methods are overseen and approved by the University of Miami Institutional Animal Care and Use Committee.