A new U of T Scarborough study finds that climate change is causing a commercially significant marine crab to lose its sense of smell, which could partially explain why their populations are thinning.
The increase in global temperature is increasing acidity level of the ocean which, in turn, seems to be discouraging the crabs from using their sense of smell to to the same extent in addition to actually degrading their ability to smell things when they do.
In the case of this species, they have poor vision, so this is impacting their ability to hunt and the population of the species. Less crabs means less crabs for fishermen to catch.