I will never forget my last day of Marine Ecology. My professor, Dr. Craig Johnson, decided to focus the lecture on marine conservation. For over two hours, he told us about how climate change was affecting coral reefs, how top predators were going extinct, and how invasive species were ruining ports all over the world. Dr. Johnson is one of the leading marine biologists in the world. His outlook on the future of the oceans was grim.
Not all of Dr. Johnson’s information was negative. He told us what we could do to improve our oceans and lessen our impact. Now, I’m going to pass that information on to you. Over 70% of commercially-sold marine fish species are overexploited. So listen up.
For starters, we need to know a little bit more about fish. The ocean is a very dynamic environment and, for that reason, certain fish species specialize in certain areas. Fish that live in the deep-sea have slower metabolisms that allow them to survive in the harsh conditions. The Orange Roughy is a great example. They do not reach sexual maturity until they are 30, and can live to be over 120 years old. They only breed in specific locations, making them even more vulnerable to overfishing. Fisherman wait for these breeding events, then go through and try to catch as many fish as possible. This is just one example of deep-sea fishing. You can probably figure out why most marine conservationists say that a total ban on deep-sea fishing is necessary.
Another big concern is the harvesting of predatory fish. As with ecosystems on land, top predators in the ocean are critically-important for balancing the food chain. They also happen to be some of the tastiest and most popular fish to eat. Fish like Bluefin tuna, swordfish, and sharks are eliciting higher and higher prices due to their increasing rarity. This simply leads to a greater fishing effort, which then decreases their numbers, which then adds to their rarity. See the cycle? These large predatory species travel widely and special methods have to be employed to catch them. Herein lies another problem: bycatch.
Bycatch consists of all the other creatures caught in the pursuit of the target fish. Huge trawl nets capture large quantities of fish, but also dolphins, sea turtles, and various shark and ray species. Traditional fishing lines, known in the fishing community as “longlines” capture birds such as albatross when they go after the baited hooks and get pulled underwater. Both fishing methods are harmful, yet are used frequently to provide enough fish to meet global demand.
Seafood is, in my opinion, the best food out there and I am not suggesting that anyone stops eating it completely. The oceans are in trouble, however, and we can help alleviate that trouble by shopping smarter.
- Avoid purchasing fish that come from the deep sea, like Orange Roughy, and never buy large predatory fish like Bluefin tuna or shark.
- Finally, and most importantly, spread the word that our oceans need help. You have more power than you think.
Peter Kleinhenz hails from Ohio, where he majored in zoology and media production at Miami University. Currently, he is pursuing his masters of science in environmental education at Southern Oregon University in Ashland, Oregon. In his free time, Peter enjoys nature photography, caving, and live music.