The tests involved monitoring changes in gastric pH, with the use of a pH data logger, during and after feeding. As food enters the stomach, acid is secreted to activate enzymes in the stomach and initiate digestion of proteins. By measuring changes in the pH of the stomach, researchers can determine when sharks are feeding. Having this information is useful in developing fishing strategies aimed at avoiding sharks when targeting other species. This was the first time studies of this type had been conducted on fish.