Dolphin gangs looking for trouble

Young moms get no rest  lazy mikura fisherman

The wind died down, and the water was very calm this morning. Still crazy cold though. We spent an hour with a large group of dolphins milling about in the shallow waters off of Kawaguchitaki. We witnessed a group of mothers with their calves and juveniles being pursued by a group of subadult males. It wasn`t obviously hostile, but the males were most certainly pestering the young mothers. Male dolphins have been known to kill young calves as a means of inducing a reproductive state in the females, so perhaps this was their intention. I talked today with other researchers about why the males pick on mothers instead of single females without calves. We thought perhaps that the males chase around the young mothers because they are easier to catch – a mother has to slow her pace down a bit in order to keep track of her young calf, so perhaps having a calf in tow makes them an easy target for the ‘attention’ of young males. In any event, we saw a lot of pestering going on today. There is always some kind of drama taking place in dolphin society!

-Justin