May 14, 2023 — Pacific populations of sweet-tasting Dungeness crabs are on the decline, and researchers from the University of Toronto say they’ve found a potential culprit: acidic ocean water related to climate change. The acidic water affects how molecules bind to the crabs’ smell-detecting antennae, which they use to scavenge for food on the sea floor.
For the Dungeness, as with most crabs, its sense of smell is critical to its survival, as it has poor vision and relies on short antennae for finding food, mating and avoiding predators. The antennae “flick” through the water, allowing scent molecules to collide with nerve cells on the appendages, which transmit to the crab’s brain.
“Losing their sense of smell seems to be climate related, so this might partially explain some of the decline in their numbers,” says Cosima Porteus, an assistant professor at the University of Toronto-Scarborough, in a press release.