How do biologists tell the age of a whale?

There are a few ways to do this and they vary in accuracy. The most obvious is by direct observation, say, someone noticed a caf appeared from a large female in a certain time, we assume it's just been born, and begin keeping track of its age, give or take a month. read more

For instance, if you have 20 dead whales, all are about 30 feet long, all are within a few months of 40 years old, you can then assume that every whale you see later alive of the same species that is also 30 feet long, should also be around 40 years old. read more

Last month researchers at the Provincetown Center for Coastal Studies, in conjunction with a team of biologists from Australia, announced they had found a new, and, they believe, much more accurate way to determine the ages of humpback whales. read more

I'm going to tell you a great story, because it sounds ludicrous but actually happens to be true. As it turns out, those hormones can be measured in a stool sample. Presumably they're measurable in a urine sample too but collecting marine mammal urine sounds pretty impossible. read more