Can whales suffocate?

After a week of severe weather in September 2019, a naturalist from the whale-watching outfitter Croisières Escoumins wondered whether whales could suffocate due to rainwater or waves accidentally entering into their blowhole. 

During a dive, a whale’s blowhole (or blowholes) is closed by “fibrous plugs” that prevent water from entering its respiratory tracts. On the surface, the whale contracts its muscles to remove the plugs, allowing it to breathe. Once the blowhole is open, water could theoretically enter the nasal cavities and cause the whale to “swallow a mouthful”. However, the subsequent exhalation should expel the water since a whale’s breath is very powerful. Therefore, it should not suffocate. 

Additionally, one of the hypotheses to explain the breaches or half-breaches performed by some whales is that they might allow the animals to breathe without having to “worry” about the waves.