For those that love seafood, it can be easy to fall into the mindset that the oceans are so vast that there will always be plenty of our favorite fish or seafood out there. In truth, each ocean creature has a tendency to have a set habitat just as land creatures do. You don't see all types of fish in every part of every ocean any more than you'd see a kangaroo naturally in the United States. In fact, some sea creatures have very small habitats. However, even those that can be found just about everywhere can become endangered due to excessive fishing.
Chilean Seabass: This is an absolutely delicious fish that many believe tastes almost like sweet lobster meat. Chefs love to work with it because it is very firm and restaurants love to serve it because it is very white and attractive, along with being tasty. Unfortunately, most Chilean seabass is a terribly endangered fish - so much so that Chilean seabass is being trafficked much like drugs. There is one way to still enjoy this delicious fish, however. If you can find those certified to have come from the South Georgia Islands which is off the New Zealand coast, then you can enjoy it guilt-free as it is not yet endangered there. Although not quite the same, you could also consider Pacific white seabass as an option or even striped bass.
Red Snapper: Although Red Snapper swims in a number of areas around the world, only the varieties around the Hawaiian Islands are not endangered. It is particularly endangered in the Caribbean. Thankfully, there are plenty of other species of snapper that are equally as tasty to choose from - consider yellowtail, black or gray snapper, for example.
Bluefin Tuna - The problem with bluefin tuna is that they take a very long time to mature to get to the huge size that fish markets make so much money on because of the popularity of sushi. There are actually restaurant chains that have paid over $1 million for just one bluefin! Quite a change for a fish that once was used only for making cat food! Chances are, most of sushi you'll find will be made from yellowfin or bigeye tuna, which you may see labeled at ahi which is its Hawaiian name.
Orange Roughy - This fish was as popular 20 to 30 years ago as tilapia is today, which resulted in their numbers being driven nearly to extinction. Because this fish can live 100 years and grows very slowly, it is going to take a while to return to a safe population. To safeguard this fish population, it is best to go with tilapia or even flounder.
There are a number of others to avoid if at all possible, including Atlantic halibut, Atlantic cod and spiny lobsters that are also dwindling in numbers. There are still plenty of fish species that are not endangered, as well as those that are farm raised. Talk with your favorite fishmonger for their recommendations for the perfect fish for your recipe or the chef at the restaurant before ordering.