Global warming could make sharks 'smaller and less aggressive'

Research shows warmer waters and increased CO2 levels can make it more difficult for sharks to catch prey

Tom Bawden Environment Editor 

Thursday 12 November 2015

Rising ocean temperatures caused by global warming could make sharks significantly smaller and less aggressive, according to new research  carried out by Australian marine biologists.

Researchers from the University of Adelaide have discovered that warmer waters and the increasing concentration of carbon dioxide that result from climate change can stunt the growth of Port Jackson sharks by making it harder for them to catch prey and also more difficult to break it down into energy. Rising levels of C02 – known as ocean acidification – reduced the sharks’ ability to smell its prey, a key weapon in its ability to hunt. 

This increased the time they took to find food and in some cases the researchers  found the sharks didn’t even bother to try, leading them to become “considerably smaller”, according to the study published in the journal Scientific Reports.

At the same time, the warmer water and longer hunting times used up more of the sharks’ energy, leaving them less with which to metabolise the food they did catch.

Read on …