Female humpback whales swim to shallows to avoid sexual harassment

The researchers said females with a calf were often pursued by males in deeper waters

Female humpback whales with calves head for the shallows to avoid sexual harassment, according to a new study.

The researchers said avoiding males helped the females save energy needed for feeding calves, helping them to survive.

The study of humpback whales around the Hawaiian Islands showed females with a calf were often pursued by males in deeper waters.

This meant the mother and calf had to increase their swimming speed by 75%.

However, as water depth decreased so did the number of males following the mother, making females more likely to be found alone with their calves in the shallows.

Unwanted attention

While previous research has shown groups containing a calf tended to be found in shallower waters, the study is the first to systematically investigate whether this is due to mothers avoiding males rather than avoiding predators or seeking calmer waters.

Continued