How old is that whale?

Australian researchers develop new method to determine whales' age: "Australian scientists are developing a new method of determining the age of humpback whales which can avoid killing the mammals in previous methods"

Kudos to the Australians for researching this. I'm not entirely too certain why we need to know how old the whales are. But since research seems to find it an important matter we shouldn't have to kill them to know how old they are!

Gary