Subject: Right whales, no pleats
Thu, 13 Mar 1997 10:11:00 GMT+1200

Many baleen whales have pleats in their skin to help them take in large
amounts of water and fish.  Why don't Right whales have these pleats?

That's a good question.  Right whales, like all other baleen whales use their baleen plates 
as a giant strainer to filter out their food from the water. But unlike many other baleen 
whales, they have developed a different feeding strategy to get their food.

One strategy is for the whales to lunge forward with mouth open, taking in huge amounts of 
water in the ventral pouch and then stopping to expell the water through their baleen, 
straining out their food. That's what the blue, sei, humpback, minke or fin whales do. 

The right whales use a different strategy.  They swim through the water slowly and strain 
the waters as they go along. They don't gulp in huge amounts of water but skim the surface 
instead. These  'skimming whales' as they are called, can swim holding their mouth open 
through the water for as long as they like. 

By the way, there's also a third method of feeding seen in Gray whales. They suck up the 
bottom mud and then strain it out, keeping the little creatures found in the mud for food. 

Nathalie Patenaude