A recent study from the University of Toronto Scarborough has revealed that ocean acidification, driven by climate change, significantly impairs the sense of smell in Dungeness crabs, a vital marine species with a fishery valued over $250 million. This research is the first to examine the physiological effects of ocean acidification on the olfactory capabilities of crabs. Key findings indicate that these crabs exhibit diminished sniffing actions, a reduced ability to detect food odors, and less responsiveness in their sensory neurons responsible for smell. The study noted that crabs exposed to acidified waters struggle to recognize odors, needing them at ten times the concentration to elicit a response. This impairment could explain the declining crab populations, which rely heavily on their sense of smell for food, mating, and habitat selection. The sensory neurons in these crabs also showed shrinkage and fewer receptors, indicating potential energy conservation. These findings may have broader implications for other crab species, such as Alaskan king and snow crabs, which may also face challenges in foraging due to similar sensory impairments related to climate-induced changes in ocean chemistry. The study was published in Global Change Biology.
