Ocean acidification could desensitize shark noses

Dogfish shark (Credit: jseattle, via Flickr)

Researchers at the Georgia Institute of Technology studying ocean acidification say that recent increases to ocean acidity may be robbing sharks of the sense of smell, according to TreeHugger. Sharks rely heavily on their noses to find food, so any sensory loss could have implications for their long-term survival rates.

Scientists used dogfish sharks for the investigation, placing them into tanks filled with water that was carbon-treated to mimic ocean conditions expected by 2050 and 2100. In both tanks, researchers found that sharks’ smelling senses were impaired.

Sharks in acidic waters ignored or completely avoided an introduced squid smell, scientists found. The exact opposite, meanwhile, was seen for a control group of sharks who underwent the same test in more basic waters. In that group, 60 percent of the sharks swam toward the smell or basked in it for a period of time.

No other stimuli besides odors were introduced during the tests because researchers wanted to make sure that the sharks weren’t relying on any other senses.

Image: Dogfish shark (Credit: jseattle, via Flickr)