Kaneohe Bay, Oahu Hawaii is well known nursery ground for the scalloped hammerhead shark. Adults come into the bay to give to their young in the spring and early summer. Pups use the bay as a protective nursery until they are large enough to enter the pelagic environment. It has been estimated that up to 10,000 pups can be born in this bay over the summer.

Little is known about the impact that this shark population has on Kaneohe Bay. One way to measure this impact is by quantifying the energetic demands of this predator.

Respirometry techniques were used to quantify the metabolic rate of the shark pups over a range swimming speeds.

 

Information on energy consumption on sharks in the laboratory was used to determine the energetic requirements of free swimming sharks in the bay. Hammerhead sharks are known as obligate ram ventilators and must continuously swim in order to breathe. We developed a custom acoustic transmitter that functions like a "pedometer".

This device produces an acoustic pulse every time the shark tail wags.

Similar techniques will be used for other species such as whitetip reef shark.