Hook, Line, and Sinker: How Overfishing Threatens the Health of Our Oceans and Our Food Supply

Human beings have been consuming fish for around 40,000 years. And our earlier ancestors were likely consuming fish for many years before that. But as is common with humans, we’ve commercialized the industry to an unsustainable tipping point. What used to be a tool for survival has now led to the total destruction of our oceans, and there seems to be no end in sight.

The world’s population keeps growing exponentially, but our natural resources are diminishing even faster. 60% of the fishing waters in the world have become entirely fished out, meaning that they are no longer able to sustain a fish population. This is not a new problem. Scientists have been sounding alarm bells for decades, but it hasn’t been prioritized by our world leaders. This has now become a global emergency. And the sad truth is it’s bordering on too late.

When does fishing become overfishing?

At one point in our evolution, fishing was sustainable. Before it was commercialized, people would only catch as many fish as they needed to survive, leaving enough fish to breed and continue the life cycle. Unfortunately, that is no longer the case.

But even as long ago as 1000 years ago, overfishing started to become an issue. One of the earliest examples was back in the 1800s when whales were overfished in Stellwagen Bank. Their blubber was used to fuel oil lamps, and the method of killing them was pretty awful. They were fished to the point of wiping out the entire population of local whales at the time.  

Overfishing essentially means that the rate of fishing surpasses the rate of breeding. When too many fish are removed from the water, the population is unable to replenish itself and therefore decreases in numbers. And sometimes, this can lead to complete extinction.

There are countless numbers of fish and marine life pulled out of our oceans every day. We can’t even fathom the quantity since the majority of fisheries have no quotas, nor is there any real way to track the amount because of poor fishing management and lack of regulation. But what we do know is that the number is substantially more than what can be naturally replenished.

What causes overfishing?

Overfishing isn’t caused by one specific thing. There are multiple factors at play that lead to overfishing which includes:


The number one reason for overfishing is the demand. People want to eat fish, so we need to provide them with fish. People are eating more now than ever, plus there are more people. We consume double what we did 50 years ago, and the human population has quadrupled. The food industry is forced to keep up with the increased demand and simply saying “don’t eat fish” is not enough to convince people not to eat fish.

Even if one fishery were to stop its practices, there would be another one right behind them. If there is demand, companies will find a way to profit from that. There are many people going vegan and vegetarian, but not enough to combat this issue. But overpopulation and love for sushi is just the start of the problem.2. Poor fishing management and lack of regulation

Poor Fishing management and Lack of Regulation

Poor fishing management and lack of regulation in the fishing industry are huge contributors to overfishing. Globally, many fisheries have no rules at all when it comes to overfishing. And if they do, they are vague or perpetuate the problem. With the size of the ocean, it’s quite the undertaking to track and police them effectively. Especially because each area has a different governing body, and none of them “own” stocks of fish in the open ocean. After all, fish can move as freely as they like! And once fishing boats enter the lawless international waters, there are basically no regulations at all.

Even as one fishing boat is stopped, dozens more make port. It seems like an unattainable goal to think that each fishing boat can be held accountable to abide by regulations, even if we had them in place. But that’s only because we have yet to try. 


Even worse, some countries provide subsidies for fisheries. An estimated $35 billion in fishing subsidies are given out worldwide, with $20 billion of those subsidies contributing directly to overfishing. Additionally, many countries provide subsidies such as covering the housing costs for fishers or the fuel costs of industrial trawlers. According to a study by Marine Policy, China has increased its fishing subsidies by up to 105%, which incentivizes fisheries and fishers to continue harmful practices.

Lack of Information

According to National Geographic, 80% of the ocean still remains undiscovered. It’s hard to set appropriate fishing quotas if we don’t even know what’s out there. Contrary to land animals, where we can approximate how many of a species live in different areas, there is no way to know this information about salmon, octopus, or lobster. Without this information, the quotas that countries are setting are likely way off and have been for years.

Lack of Understanding

Although we lack information about the fish and marine life population, we also lack understanding as a society. They say ignorance is bliss, and because we can’t see what’s going on in the fishing industry and under the water, it’s easy for us to disregard it. As long as there is still fish available in restaurants and supermarkets, people will continue to purchase it without giving it much thought, which is why documentaries like Seaspiracy and The End of the Line are so important.  

The effect of overfishing on our oceans

So, we know what is causing overfishing, but how is that actually affecting our oceans?

Loss of Biodiversity

Removing fish and marine life from their habitat not only affects the creatures themselves but also throws off the entire ecosystem. If a larger, predatorial fish species is being overfished, the entire food chain will be impacted. For example, a larger fish, like a Yellow-tail Snapper, will consume a smaller fish, like an Atlantic Blue Tang. Blue Tangs live off seagrass and algae. By overfishing Yellow-tail Snapper, the population of Atlantic Blue Tang would skyrocket, causing them to consume a high volume of seagrass. Many species of marine life rely on the seagrass for protection, and without it, they are easy targets. You can see how this can become an issue.

Additionally, overfishing puts our fragile coral reefs in serious danger. About 25% of marine species are dependant on coral reefs for survival. Fish and coral reefs have a symbiotic relationship. The natural enemy of coral is algae and seaweed, which can eat away at it. Fish eat the algae and seaweed, keeping the reef healthy and promoting growth. With no fish, there is no coral reef.

Huge volumes of bycatch

Arguably the most devastating impact of overfishing is the incomprehensible amount of bycatch pulled out of the water by fishing operations. Bycatch is any “unwanted” fish or marine species caught while commercially fishing for something else. And nearly 40% of fish caught globally are captured unintentionally. And what happens to bycatch? The sad truth is that it’s almost all discarded, with most bycatch already deceased or dying.

Consider this: what are the chances that shrimping boats go out to catch shrimp, and catch nothing but shrimp? Very slim. In fact, for every pound of shrimp caught by shrimping boats, there are approximately 20 pounds of bycatch. That would be like throwing away 20 pizzas for every one pizza you eat!

One of the most significant contributors to bycatch is ocean trawling, where fishing boats drag huge nets behind them, capturing anything and everything in their path. So, you could have a commercial tuna boat trawling for tuna, but it will also catch sharks, dolphins, turtles, sea birds, and many different species of fish. The tuna boat doesn’t need these other animals, so they pick out the tuna and chuck everything else back into the water. Often by the time this happens, the bycatch is already dead.

Additionally, there is the practice of dredging, which is typically used to collect oysters, crabs, scallops, clams, and other bottom-dwellers. Rather than being dragged through the open water like a trawling net, a dredge is dragged along the bottom, trapping bycatch and damaging coral and other underwater habitats.

Ghost fishing gear polluting our oceans

Fishing gear makes up 10% of all plastic debris in our oceans. While fishers likely don’t want to lose their equipment (after all, it’s their livelihood), nets, lines, and ropes can become torn or trapped when trawling or dredging. It’s also the most deadly form of plastic in the ocean because it’s easy for marine life to become trapped, usually leading to a traumatic death by either suffocation or exhaustion trying to break free.

While sometimes this fishing gear ends up in the ocean accidentally, it’s often abandoned or just thrown overboard if it’s no longer useable. The reason it’s called “ghost fishing gear” is because it’s gear that essentially keeps fishing, even without a fisherman.

Algae overgrowth

Many different forms of marine life consume algae. Shrimp, crabs, snails, zooplankton, and small fish are just some of the marine creatures that love to munch on this aquatic plant. Higher on the food chain, larger fish and sharks eat them. When a species is overfished, they are no longer around to feed on the algae, causing it to overgrow. Algae is incredibly acidic, and too much of it directly impacts the coral reefs and the fish that live there.

As we mentioned before, algae can completely take over and damage fragile coral reefs. On top of that, too much algae blocks out the rays from the sun, which are essential to feed other aquatic plants. Not to mention it consumes tons of oxygen.

Marine Species on the Verge of Extinction

There are tons of marine species that are now on the verge of extinction due to overfishing, and some might surprise you. Fish including multiple types of tuna (Bluefin, Bigeye, Albacore, Yellow-fin, and Skipjack), Atlantic Halibut, Hawksbill Turtle, Sawfish, and Nassau grouper are all on the verge of extinction due to overfishing. It’s estimated that since industrialized fishing began, the population of large predatory fish has been reduced by 90%!

What can we do to stop overfishing?

Putting a stop to overfishing can seem like a daunting task, and significant change needs to come at a government level. Increasing funding for fishing management and regulation needs to happen if we are going to reverse the damage that’s been done. That includes more protected marine areas and places where fishing is prohibited to allow fish populations to repopulate. We need stricter quotas and more enforcement to ensure that fisheries adhere to guidelines. 

Banning trawling and dredging is also an essential step to reducing the amounts of bycatch caught and killed in nets.

That said, there are many things we can all do as individuals to help end overfishing and its negative impacts. Taking fish and seafood off your plate is a great place to start. Less demand reduces the amount of fish that needs to be caught. Additionally, educating yourself and others on the effects of overfishing can spread awareness and ensure we are all making conscious choices.

There are also many amazing organizations working on a bigger scale to combat overfishing and protect our oceans that can use our support. You can donate, share their resources, or even volunteer! Some great ones include:

-     Sea Shepherd Conservation Society

-     Coral Reef Alliance

-     Marine Conservation Institute

-     The Ocean Project

-     World Wildlife Fund International

-     Seaspiracy  

Let’s end overfishing

Change is necessary if we want to save our oceans. While one person can’t alter the entire fishing industry themselves, if we all work together, we can make waves and inspire change. Lead by example and make eco-friendly choices in all aspects of your life to encourage others to do the same.