Is the statement "barnacles are found on the bottom of boats because they don't like the cold air on top of the boat" an observation or inference?

The statement "barnacles are found on the bottom of boats because they don't like the cold air on top of the boat" is an inference. This is because it takes a specific observation (barnacles being found on the bottom of boats) and attempts to explain it with a reasoning about their preference for temperature, which is not directly observable.