I tried out Oceanminds, a social network that describes itself as "Ocean preservation through social networking" was founded by Nico Danan and Cliff Etzel. Think of Facebook but for ocean enthusiasts. I believe this just launched today, but people are already signing up.
Says Nico and Cliff: "We decided it was time to regroup the water tribe in one place on the web to promote the environmentally conscious lifestyle of the Ocean Minded people. Exchange ideas, content, photo, video and share projects to promote a healthy environment and most of all to continue to enjoy the Blue Planet for generations to come!"
Definitely worth checking out...