The Huffington Post has a feature on the 9 problems destroying our oceans; overfishing is #1.

Here’s one thing you can do to help: Download this free iPhone app, the Monterey Bay Aquarium Seafood Guide.

It’ll tell you what fish you should avoid buying/eating, either because it’s overfished, farmed in an environmentally damaging way, or could be mercury-infused: Don’t eat chilean seabass, Atlantic cod, mahi mahi, Atlantic halibut, and so on; do have Pacific halibut, Alaskan wild salmon, and shrimp from the Gulf of Mexico.

I used this app at a restaurant on Saturday night and got the answers I wanted. Who knows—the chef may have been lying—but at least he or she knew that people care where their food comes from, and that it be harvested in a sustainable fashion.