UPY 2025

UPY 2016 Behaviour - Highly Commended
'Crunch'
Theresa A. Guise

Isla Guadalupe is well-known for aggregation of great white sharks from August through January each year. From a surface cage on the Solmar V, I was observing five great whites feeding on tuna served up in the water when, out of the blue, a turtle entered the mix. The sharks paid little attention to the turtle until it tried to eat the tuna, at which time the sharks nudged it away from the food. The turtle kept returning to eat the tuna, only to be bumped away several times. Finally, the turtle saw a piece of tuna floating near my surface cage, and started to eat it. A great white followed, and bumped the turtle away one final time. When the turtle returned, an exasperated shark grabbed the turtle with its massive jaws and a loud "crunch" was heard as far down as the 30 foot submersible cage below. The shark then spit the turtle out, and the turtle swam away. Pre-crunch images of the turtle showed that the turtle already had a cracked shell and suggest that this turtle was no stranger to the bite of the great white shark.