Start Your Own Photographic Nature Catalogue

Put together a catalogue of photos you've taken of the different nature you have seen, then add to your collection!
Start with one 'topic', like butterflies, ferns, insects, birds, roses, mammals, food, etc, and branch out as you are able.
Perhaps keep your collection on an online photo sharing site so you can easily show and share your list of images with your friends.

You can include a way to note if an animal or plant was 'wild' or captive/planted. (If you have a scoring system, you'd get triple points for a 'wild' photo.)