What is bycatch?

What is bycatch? I could probably tell you in a straightforward manner, but I think that a convoluted cereal analogy will be the narrative route I’ll be taking today. Imagine you’re eating a bowl of Froot Loops, but for whatever reason you refuse to eat any color aside from the yellow ones. Easy enough, you can just reach into your cereal bowl, pick out the yellow Froot Loops, and eat those. But would it really be a convoluted cereal analogy if you weren’t wearing a blind fold while eating said bowl of Froot Loops? Probably not. So naturally, despite your goal of ONLY retrieving those prized yellow rings from the bowl, you can’t see anything that happens once you dunk your spoon beneath the surface and come up with - OH NO! Red ones? Blue ones? Orange? GREEN?? Why, that’s simply criminal. You take your blindfold off, and discard the non-target colored loops, leaving them to their cereal-analogous form of death. 

This - plus or minus a few breakfast carbohydrates - is essentially what bycatch is. The large scale fishing operations that supply the near entirety of our global seafood markets catch a lot of fish. They don’t have the time or resources to ensure that when they set their longlines or drag their trawls through the water, they’re only catching the specific target species. Underwater, (and just like Froot Loops!), fish don’t sort themselves by color, species, sex, or size. Anything brought up that can’t be sold or is legally prohibited from being removed is thrown back into the ocean, dead or dying with very poor odds of survival. 

Many people are aware of bycatch or find it unfortunately intuitive once they hear about it for the first time. After all, there’s no entirely efficient or waste-free system that has the ability to feed billions of people. But what most aren’t aware of is the immense scale of this problem and its consequences for both the marine ecosystem itself as well as us humans, who just so happen to be fish-eaters, oxygen breathers, and coastal community- economy supporters. So now get ready for some unpleasant statistics.

An average of 40% of all marine catches are estimated to be bycatch. Taking exams at this particular academic institution has definitely restructured my brain to accept certain low percentages as normal, but certainly not enough to think that it makes sense for just 60% of marine animal deaths to go towards feeding people. But unfortunately, it gets even worse than this when you look at shrimp trawling in particular. Trawling is about as unselective as you can get and the bycatch rate in the average shrimp operation is between 80 and 90%. Despite only constituting 2% of global seafood by weight, the methods used to catch shrimp account for 33% of global bycatch. In addition to trawling operations, longline fishing was found to kill 4.5 million sea animals yearly, including 3.3 million sharks, 75 thousand albatrosses, 60 thousand sea turtles, and 20 thousand dolphins and whales.  

The impact on the ecosystem is severe. There are restrictions that set a minimum on the size of fish that can be taken, so anything that doesn’t fit these requirements is usually killed as bycatch. Obviously an unnecessary dead fish is never a good thing, but the reason why it’s especially problematic for younger, smaller fish to be killed disproportionately to mature adults is because they are much less likely to have reproduced. This is bad news for the propagation of the species and also has trickle down effects for the entire ecosystem due to the disruption of the predator prey balance. 

In the same way that there are size restrictions for what can legally be brought back to shore, there are also laws that attempt to prevent the capture of endangered species. These laws however, are not powerful enough to prevent endangered animals like whales and sea turtles from accidentally getting caught, and then getting injured or dying before being returned to the water. One particular species, the vaquita, found only in the northern Gulf of California is down to just 10 individuals for this reason. This is just not something that should happen to something that carries the impressively cute title of ‘World’s smallest porpoise’. (If you want to be extra sad, note that I just had to go back and delete ‘20’ vaquitas left and write ‘10’ because my original source was 4 years old.)

Bycatch is clearly a huge problem, and certainly won't be changed overnight. However, as consumers, we drive the market with the choices we make every day. Being aware of problems like bycatch has more of an impact than we realize and you don’t have to stop consuming these foods entirely to make a difference.