Ocean acidification is already making it harder for fish to find friends, for corals to grow, and formussels to remain attached to hard surfaces, just to name a few effects. Now, new research reveals that it may be taking a toll on sharks' ability to track prey.
A team of researchers recently found that acidic waters cut adult smooth dogfish (Mustelus canis) sense of smell. Researchers simulated climate forecasts for 2100 in tanks and filled them with the scent of squid, a favored prey source for smooth dogfish, and found that the sharks didn't effectively respond to the scent in these projected conditions.
"The sharks' tracking behavior and attacking behavior were significantly reduced. Sharks are like swimming noses, so chemical cues are really important for them in terms of finding food," Georgia Institute of Technology assistant professor Danielle Dixson said in a news release.
To carry out the study, researchers tested 24 sharks in a 32-foot long pool with two 'lanes' like in a swimming pool. Researchers pumped squid odor down one lane, and normal seawater down the other. The sharks were then divided into groups and spent time in holding pools with either normal, mid, or high concentrations of carbon dioxide, without food, before being put back in the pools with squid odor.