I've been to Lake Martin many times. What you see changes as the seasons do. Some times all you see are nutrias, sometimes tons of different kinds of birds. Others lots of alligators. A drive down Rookery road holds something different around every turn. Its a must see destination.
We found Lake Martin as we arrived for a tour of the swamp with Cajun Country Tours (which we can recommend).
Along with tours there is a boardwalk where you can venture into the lake and see the swamp areas near that boardwalk.
There is a rookery for the birds there, which was closed to visitors since we visited during...
I love photography and I couldn't of found a better place than Lake Martin. There were so many birds, we lost count of the alligators because we saw so many. The guides take you in on motorized boats which procede slowly which is great for taking pictures. I highly recommend a visit here, I loved it.