Have you ever wondered if a tuna fish could attack and kill a human?
While they are some of the top predators in the ocean, there are no records of tuna attacking people. In fact, their diet consists of smaller prey than sharks or killer whales, so there is no danger of mistaken identity leading to an attack.
However, the tuna industry is not only terrible for the environment and human health, but it’s also hell for the animals who are trapped and killed.
In this article, we’ll explore the truth about tuna fish and their potential danger to humans, as well as the devastating impact of the tuna industry on both animals and our planet.
Can A Tuna Fish Kill A Human?
Tuna fish are not known for attacking humans. Unlike sharks who have been known to attack people having confused them for other prey, there are no records of tuna attacking people. This is because even the largest tuna’s diet consists of smaller prey than sharks or killer whales, so there is no danger of mistaken identity leading to an attack.
On a broader scale, tuna hunt and eat small fish and squid by chasing them down and swallowing them whole. They are evolved for high-speed cruising to cover huge stretches of low-productivity oceans and congregate around features that might attract smaller fish. They feed by gulping small fish that are balled into schools, not tearing or attacking with teeth. Tuna don’t have the big, gaping mouths for taking down large prey.
While it’s highly unlikely that a tuna would attack a human, it’s important to note that consuming tuna can be harmful to human health. Tuna flesh is loaded with heavy metals that attack the heart muscle, so the toxicity outweighs any possible health benefits of omega-3 fatty acids. According to a recent study published in the American Heart Association’s journal, men with the highest levels of mercury increased their risk for heart disease by 60 percent and their risk of dying of a heart attack by 70 percent.
Tuna Fish Behavior And Diet
Tuna fish are known for their active and social behavior, often swimming in schools with other predatory fish species, including other tuna. They spend most of their time swimming around the oceans, which requires them to eat up to 25% of their body weight every day just to maintain their powerful muscles.
The diet of tuna fish varies depending on their location and species. Tuna that hang out by the ocean’s surface primarily eat squid, while those that spend most of their time in deep waters tend to eat cephalopods and fish. Juvenile tuna eat zooplankton during the early stages of life. Bluefin Tuna, with their large size and quick aggressiveness, consume a variety of prey including herring, sanddabs, anchovies, mackerel, flying fish, squid, shrimp, eels, and surfperches, as well as smaller tuna.
Adult Bluefin Tuna have been known to reach top speeds of more than 40 mph, so they don’t have any issue hunting in the open water. Their diet is not limited to just fish; they also eat a variety of crustaceans, including crabs, lobsters, crayfish, shrimp, krill, and barnacles. They have also been known to eat octopuses, squid, cuttlefish, and even kelp.
Tuna fish are apex predators and consume a wide variety of other fish and squid. This helps keep the populations of other species healthy and balanced. They are also among the most commercially valuable fish on the planet and support artisanal and industrial fishing alike. However, some species are disappearing due to overfishing driven by high demand and prices in sushi markets.
Are Tuna Fish Dangerous To Humans?
While tuna fish may not pose a direct danger to humans, consuming them can be harmful to human health due to their high levels of mercury. Mercury is a toxic heavy metal that can cause severe health effects, particularly in vulnerable populations such as young children and pregnant women. Natural processes and industrial activities such as volcanic eruptions and coal burning emit mercury into the atmosphere or directly into the ocean, where it builds up in marine life. Tuna, being a large ocean fish, can contain higher-than-average amounts of mercury.
Certain types of tuna are particularly high in mercury, such as bigeye tuna, and should be avoided by small children and pregnant or breastfeeding women. For most healthy adults, it is recommended to consume at least 2 servings of fish per week, which can include tuna. However, it is important to select varieties of fish that are low in mercury, such as canned light tuna, and limit their intake based on the recommendations set by the FDA.
Mercury pollution has increased since industrialization, but accumulation of methylmercury in animals is a completely natural phenomenon. Even fish caught from the middle of the ocean, far from any polluting sources, will contain methylmercury. Consuming too much mercury is linked to serious health issues such as finger curling, cognitive impairment, and coordination problems. In extreme cases, mercury poisoning can cause weird symptoms like tingling sensations and loss of balance.
The Environmental Impact Of The Tuna Industry
The tuna industry has a significant impact on the environment, particularly in terms of overfishing and climate change. Tuna are a top predator in the marine food chain and help to maintain a balance in the ocean environment. Overfishing of tuna poses serious threats as loss of predators allows populations of prey species to expand, leading to a destabilized food web and marine environment. In 2011, the International Union for Conservation of Nature classified seven of the 61 known tuna species in a threatened category, being at serious risk of extinction.
Furthermore, the tuna industry contributes significantly to climate change. Tuna fishing requires large amounts of fuel, and purse seining, a common method used to catch tuna, is less sustainable than selective methods because other species get swept into the net. The drop in purse seining in the US tuna fishery since about 1990 has led to catching a tonne of tuna taking about three times as much fuel today as it did 25 years ago. Sustainably caught tuna still has a larger climate effect than any other protein considered, except beef, for which climate warming emissions are five times that of tuna per unit of weight.
In addition to overfishing and climate change, the tuna industry is associated with major supply chain risks such as illegal, unreported and unregulated (IUU) fishing and the bycatch (part of the catch which is not targeted and is discarded dead) of threatened and endangered species. These activities threaten the sustainability of fisheries, marine ecosystems and livelihoods.
However, there are signs of progress in protecting international waters’ biodiversity by ensuring tuna stocks are healthy, that the impact on the ecosystem is minimized and that global fisheries are well-managed. For instance, between 2014 to 2019, the number of major tuna stocks experiencing overfishing went down from 13 to five. Rebuilding eight fish stocks to reach a healthy level is no mean feat. Additionally, bycatch and marine pollution have been reduced. Consumers can also do their part in protecting tuna by ensuring the tuna they buy is sustainable.
The Health Risks Of Eating Tuna
While tuna is a nutritious food, it’s also high in mercury compared to most other fish. Mercury is a highly toxic metal that can cause severe health effects, including poor brain function, anxiety, depression, heart disease, and impaired infant development. Mercury is odorless and invisible to humans, but once in the body, it can act as a neurotoxin and interfere with the brain and nervous system. Exposure to mercury can be especially harmful to small children and people who are pregnant.
When the brain of a child develops, it rapidly absorbs nutrients. Mercury can affect that absorption, causing learning disabilities and developmental delays. In infants and fetuses, high doses can lead to cognitive difficulties, cerebral palsy, deafness, and blindness. In adults, mercury poisoning can affect fertility and blood pressure regulation. The side effects of mercury poisoning include finger curling, cognitive impairment, and coordination problems.
Tuna fish accumulate toxic mercury in their flesh as a result of industrial pollution. A California boy who ate canned tuna went from being a star athlete and honor student to being unable to concentrate or catch a football because of the side effects of mercury poisoning. Even if he had eaten only half a can of albacore tuna a week, he still would have consumed 60 percent more mercury than is considered “safe” by the U.S. government.
While it’s important to be aware and informed about potential health hazards of eating canned fish, keep in mind that by eating a balanced diet and consuming a moderate intake of tuna per week, which the FDA recommends as 2-3 servings, you can reap the benefits of tuna without most of the side effects. However, excessive consumption of tuna, even canned tuna, is bad for your long-term health. Therefore, it’s essential to eat tuna in moderation—not every day—to avoid the potential health risks associated with mercury exposure.
Alternatives To Tuna: Sustainable Seafood Options
If you’re looking for a sustainable seafood option that’s not tuna, there are plenty of alternatives to choose from. Here are some of the best sustainable seafood options that you can try:
1. Sardines: Sardines are a great alternative to tuna because they’re low in mercury and high in omega-3 fatty acids. They’re also a good source of protein, vitamin B12, and vitamin D. Sardines are usually caught using sustainable fishing methods, such as purse seine nets or handlines.
2. Mackerel: Mackerel is another fish that’s high in omega-3 fatty acids and low in mercury. It’s also a good source of protein, vitamin D, and vitamin B12. Mackerel is usually caught using sustainable fishing methods, such as hook and line or gillnets.
3. Clams: Clams are a type of bivalve mollusk that’s sustainable to farm or harvest. They’re also a good source of protein, iron, and vitamin B12. Clams can be cooked in a variety of ways, such as steamed, baked, or fried.
4. Scallops: Scallops are another type of bivalve mollusk that’s sustainable to farm or harvest. They’re also a good source of protein, magnesium, and potassium. Scallops can be cooked in a variety of ways, such as seared, grilled, or baked.
5. Arctic char: Arctic char is a type of fish that’s similar to salmon but has a milder flavor. It’s high in omega-3 fatty acids and low in mercury. Arctic char is usually farmed using sustainable methods, such as recirculating aquaculture systems.
6. Tilapia: Tilapia is a type of fish that’s commonly farmed and is considered to be sustainable. It’s also a good source of protein and low in mercury. Tilapia can be cooked in a variety of ways, such as grilled, baked, or fried.
By choosing these sustainable seafood options instead of tuna, you can help support healthy fish stocks and reduce the pressure on certain fish populations. Plus, you’ll be able to enjoy delicious seafood without worrying about the harmful effects of mercury on your health.
