Smell is important for fish to gather information about their environment in order to find food and avoid predators. Unfortunately, rising atmospheric carbon dioxide emissions are interfering with this. Since oceans absorb about a quarter of the carbon dioxide in the atmosphere ocean water is becoming more acidic. This interferes with the sense of smell in ocean fish. Researchers have calculated that higher dissolved carbon dioxide levels force fish to be ~42% closer to the source of a smell in order to detect it.
- Fish can use their sense of smell for survival and for location finding. They have nasal receptors in their nasal cavity that work similarly to the way humans’ work.
- The annual increase in atmospheric carbon dioxide is making the oceans more acidic.
- To study the effects of changing ocean chemistry on the survival of fish and their effects on the food chain, the researchers used the ocean sea bass as their model.
“These changes in ocean chemistry have been shown to affect the behaviour of some fish, even making them prefer the smell of their predators.”