Jumping conchs triumph at overheated athletics

Conchs famed for one-footed jumping can beat many fishes at oxygenating athletic performance at high temperatures.

Hunchbacked conchs (Gibberulus gibberulus gibbosus) can jump away if they sniff a predatory cone snail creeping near. But signs are mixed on how climate change will affect conch athletics. In the lab, conchs collected from the Great Barrier Reef could still increase oxygen delivery in their circulatory systems during epic jumping when researchers heated aquariums to 38° Celsius, Sjannie Lefevre of the University of Oslo in Norway and her colleagues report October 7 in the Journal of Experimental Biology. At those temperatures, many reef fish are dead, Lefevre says.

At the high temperature, the conchs’ oxygenation still had about the same margin of safety as it does at water temperatures today. That margin didn’t decrease much when researchers mimicked seawater pH expected when carbon dioxide hits 450 to 1,000 parts per million, predicted for 2100. What did decline was the share of conchs that started doing any jumping.