Fish. They say to eat fish. Fish was always a low fat, healthy food. Brain food.
But now that omega-3 fatty acids are all the rage, health experts are telling us to eat fish as often as three times a week. That’s a lot of fish! In these days of declining fish stocks and overfishing, how responsible is it for us to eat that much fish?
The fisheries industry today faces various environmental problems. The most obvious is overfishing. Some popular fish are being taken out of the ocean to fill our bellies faster than they are able to reproduce. Such fishy favourites as Chilean seabass, orange roughy, pacific red snapper and swordfish fall into this category. So, filling up on these delicacies three times a week, or even once in a while, is supporting an unsustainable industry.
Another environmental problem facing the fishing industry is “bycatch.” This is a lot like “collateral damage” in that innocent bystanders get hurt. Bycatch is a term describing marine life that is not being fished for, but gets entangled, impaled or otherwise caught by the net, hooks or trap used to catch the target fish. The most famous example of this is, of course, dolphins, which are caught in tuna nets. Other examples include sea turtles, which can be caught in shrimp trawl nets.
Dolphins and sea turtles do better these days because of increased awareness of their plight and because they are fairly large animals. Smaller animals such as immature fish are not so lucky, and are often inadvertently killed.
Most fisheries throw back bycatch, but these animals are often so damaged after being caught that they die. Research is currently underway to find fishing techniques that minimize or eliminate bycatch, but, currently, the Monterey Bay Aquarium estimates one in four animals caught in fishing gear dies as bycatch.
A third issue facing the fishing industry today is damage to habitat. Habitat can be damaged by fishing techniques such as trawling, which is when a net is dragged through the water, often along the sea floor. Trawling damages the sea floor, which is where many fish breed and feed, and, once damaged, the sea floor can take centuries to regenerate. Fish that are caught by trawling or dredging include clams, scallops, shrimp, prawns, snappers and sole.
Does this list of woe mean we can’t eat fish? Do we have to forgo our omega-3? No. Happily, there are some fish we can eat without feeling too guilty. Although some fish farms do cause pollution, some species can be farmed sustainably. These fish include tilapia, sturgeon, trout, striped bass, scallops, catfish, oysters and mussels. Other wild fish are well-managed and their populations are healthy. These fish include anchovies, bluefill, dungeness crab, halibut, mahi mahi and pacific albacore tuna.
We have mentioned some freshwater fish in this article but have focused on ocean fish.
However, let us not forget that we have a local, freshwater fish industry. That, however, will have to be a subject for another column.
Andrew Laursen is an assistant professor at Ryerson University, studying ecosystem ecology. Sophia Dore is an environmental scientist with Conestoga-Rovers & Associates, an environmental consulting company.
| dolphin fun fact |
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Dolphins sleep with one half of their brain plus one eye closed, then switching to the other side of the brain and the other eye closed during other parts of the day — slowing down everything inside their bodies and moving very little. |
