These close-up pics were taken as part of the BBC One series Ocean Giants. Here's a humpback whale making a splash off the coast of Hawaii.
Another impressive mammal is this bowhead whale - they are the fattest animals in the world. They have up to 50 tonnes - the weight of about 10 elephants - of body fat to keep them warm and snug.
And this huge creature is a southern right whale - who seems to have got a new diver friend!
Say hello to this blue whale - they're the largest animals in the world!
Let's step back and have a full view of the underwater giant. These blue whales can weigh up to 200 tonnes - the same as about 40 elephants - and can be a whopping 30m long.
This grey whale looks a bit grumpy. They travel from warm breeding grounds at the equator to their summer feeding grounds in the Arctic and it's thought to be the longest yearly trip that any mammal makes.