Both are chock full of amazing photos of their designated animals and their habitats.
Ocean Animals gives you bite-sized information about many animals. I love the wonderful photos, but it also has tid-bits of info around a picture that points out particular features on an animal. There is a section called "Info Bites" that give the name, type of animal, home, and size along with size comparison so we can see how large or small each animal is. For example the whale shark is as big as a school bus, that is background knowledge kids have and can use to compare. Also within the Info Bites is a global map that shows the range where the animal lives.
These non-fiction books will be used so much at my library because of those gorgeous photos and the small bites of information. This way children can learn a little about a lot of different animals. If they want to learn more there are other books on just one animal that they can go to next. Because of the their ease of use I'd use these with Preschool and older, up to middle school age. They have something for everyone.