In honor of our Atlantic Tunas Art Contest, we wanted to share some fun facts that might inspire the young artists who are entering this year!
Tuna are amazing fish that undertake huge migrations across entire oceans. They are incredibly fast swimmers built for covering vast distances. That being said, tuna are in danger from many dangerous ocean animals that want to eat them. Tuna have developed smart defenses and ways to stay alive to help them avoid being eaten on their dangerous journeys.
Schooling Behavior
One of the main ways tuna protect themselves is by sticking together in large schools Schools can number in the hundreds or even thousands of individual fish. There is safety in numbers A single tuna would be easy pickings for a predator, but a whole tightly coordinated school is a much more difficult target.
Schooling improves tuna survival in several key ways
-
Predators are less likely to target a single tuna when faced with a large school of thousands of fish. The odds are against any one tuna being the unlucky victim.
-
The many eyes of the school provide an early warning system. When one fish spots a threat, the whole school can quickly react.
-
Their tight, synchronized movements confuse predators. It’s hard for predators to isolate and grab a single tuna in the chaos of the swirling school.
-
The school can mob predators with aggressive behavior to drive them away. No predator wants to get caught in a bashing storm of hundreds of tuna!
Speed and Endurance
Tuna are streamlined for speed and built to swim constantly. Their torpedo-shaped bodies and smooth skin glide through the water with little drag. Their specialized tail fins provide powerful propulsion at high speeds.
Some tuna like albacore can surpass 50 miles per hour in bursts. Even the fastest ocean predators like sharks can’t match the tuna’s top speed. Their non-stop endurance also allows tuna to simply outswim predators over long chases.
Keen Vision
Tuna have excellent eyesight. Their eyes are specially adapted to focus quickly when moving at high speeds. Their vision combined with schooling gives tuna quick reaction time to looming threats. Whether it’s a shark attack or marlin ambush, tuna can rapidly take evasive action and speed away from danger.
Strength in Numbers
There is strength in numbers when tuna team up to mob potential predators. When faced with a threat like a shark or marine mammal, the school moves as one to aggressively charge the intruder. A wall of hundreds of tuna ramming the predator is an intimidating sight.
Schooling tuna take turns leading these mobbing efforts. Each gains protection from being in the center of the school. The mobbing behavior often convinces the predator to look for easier prey elsewhere. Even most apex predators choose avoidance over injury.
Keeping Deep
Tuna like bluefin are specially adapted to make deep dives exceeding 1,000 feet. By sticking to deeper water, they reduced their exposure to surface-dwelling oceanic predators like sharks and marine mammals. The colder temperatures of the deep also help regulate their warm-blooded physiology.
Hiding in Plain Sight
Tuna rely on camouflage to avoid predators when not in large schools. Their steel gray to dark blue backs blend in with the dark ocean depths when viewed from above. Their light undersides match the brighter surface waters when viewing them from below. This countershading makes them hard to spot by predators approaching from any angle.
Never Stop Moving
Tuna never stop swimming, even when resting. They are specially adapted to get oxygen while moving with their mouths open. This constant motion makes it hard for predators to approach them while sleeping. At the first sign of danger, tuna can instantly accelerate to escape speed from their persistent forward movement.
Safety in Numbers
Tuna stick close to other schooling prey fish like herrings and anchovies. These huge bait balls create confusion and give tuna time to escape when a predator attacks. Often sharks and other predators content themselves with picking off some of the bait fish while the tuna flee to safety.
Staying Deep
Some tuna such as bigeye tuna are specially adapted to hunt prey at extreme depths. By diving deep, they reduce encounters with predators common in surface layers. The deep diving ability also allows tuna to escape predators at the surface by simply vanishing into the depths where most predators can’t follow.
Aggressive Defense
When no other options are available, tuna will turn and aggressively attack predators. They bash sharks and billfish with their stout bodies and whip them with their tails. Their tough skin and dense muscles allow them to ram predators with little chance of injury. Even a apex predators think twice after being thrashed by a feisty tuna.
Tuna have many adaptations and strategies that improve their odds against a wide array of ocean predators looking for a tasty tuna meal. Schooling, speed, stamina, strength in numbers and simply avoiding predators by staying deep are key survival methods. Tuna will also turn the tables and take the offensive when necessary. These behaviors allow tuna to complete their extraordinary migrations in the face of constant predation dangers.
Tunas are very fast swimmers.
Thanks to their unique torpedo-shaped bodies, smooth skin, and streamlined fins, tunas are fast swimmers. Albacore tuna can swim faster than 50 miles per hour. This helps them catch prey, avoid predators, and cover a lot of ground quickly during annual migrations.
Tunas are known for being top predators—but they are also prey.
All tuna species are predators. Their bodies are shaped like torpedoes, which gives them an edge over species that are slower and less mobile. Their sharp eyesight also helps them catch prey. Tunas eat a varied diet including fish, crustaceans, and squid. Little skipjack tuna eat a lot of different kinds of fish, like herring, crustaceans, cephalopods, mollusks, and sometimes even other little skipjack tuna.
Tunas are also a favorite prey species for top ocean predators. A tuna’s speed and agility comes in handy when avoiding hungry sharks, billfish, and toothed whales. Smaller tuna species (like skipjack) and juveniles also have to avoid other larger tunas looking for a meal.
Yellowfin tuna swimming away from a shark. Credit: iStock
Tuna – The Forgotten Superpredators
FAQ
How do tuna protect themselves from predators?
How do fish protect themselves against predators?
Who is the predator of tuna?
How do tuna survive?
How do fish protect themselves from predators?
Schooling is one of the primary ways many fishes help defend themselves from predators. About 80 percent of all fish species school as juveniles and roughly 20 percent school as adults. Many ichthyologists say that the concept of “safety in numbers” plays a fundamental role in schooling behavior.
Do fish have a defense mechanism?
While most fish have some form of defense mechanism, there are a few species without any known defenses. These species often rely on their swift movements and agility to evade predators. For example, certain types of tuna and marlin do not possess any known defense mechanisms.
Why is it important to protect tuna?
Many of the world’s valuable tuna species face urgent threats to their continued existence, including significant population declines, poor international conservation management, and high levels of illegal, unreported, and unregulated (pirate) fishing. It is important to protect tuna.
Why is tuna consumed?
Tuna are among the most commercially valuable fish on the planet and are consumed for their nutritional and economic value. They are an apex predator and consume a wide variety of other fish, including squid, herring, and sardines. This keeps the populations of other species healthy and balanced. Tuna underpin the ecosystems and economies where they live.