Reduced odor tracking in sharks as ocean acidification increases

September 10, 2014

Projected future CO2 levels impair odor tracking behavior of the smooth dogfish (Mustelis canis)

This study reveals that sharks treated with high levels of CO2 significantly avoid odor cues indicative of food, while both individuals treated at mid CO2- levels and at a current-day control maintain normal odor tracking. Additionally, sharks treated under both mid and high CO2 conditions reduce attack behavior compared to the control individuals.  

These findings show that shark feeding could be affected by changes in seawater chemistry projected for the end of this century. Understanding the effects of ocean acidification on critical behaviors, such as prey tracking in large predators, can help determine the potential impacts of future ocean acidification on ecosystem function.

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Marine protected areas might not be enough to help overfished reefs recover

August 21, 2014

Young corals and fish turned off by smell of damaged habitats

Damaged coral reefs emit chemical cues that repulse young coral and fish, discouraging them from settling in the degraded habitat, according to new research. The study shows for the first time that coral larvae can smell the difference between healthy and damaged reefs when they decide where to settle.

“If you’re setting up a marine protected area to seed recruitment into a degraded habitat, that recruitment may not happen if young fish and coral are not recognizing the degraded area as habitat,” said Danielle Dixson, an assistant professor in the School of Biology at the Georgia Institute of Technology in Atlanta, and the study's first author.

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