The Shortfin Mako shark (Isurus oxyrinchus) is a legendary oceanic predator celebrated for its explosive speed and exceptional athletic ability. This powerful, open-ocean hunter targets fast-moving prey like tuna and swordfish. The common perception is that the Mako shark is the fastest fish in the sea, a reputation earned through documented bursts of acceleration and spectacular leaps. This status as the ocean’s speed champion raises the question of whether this claim holds up to scientific scrutiny compared to other marine speedsters.
Defining the Mako’s Velocity
The Shortfin Mako shark is widely regarded as the fastest shark species, but pinpointing its exact maximum velocity is a significant challenge for researchers. Anecdotal reports often attribute incredible burst speeds, suggesting it can reach 46 to 60 miles per hour (74 to 97 km/h) in short, powerful accelerations. These high figures frequently stem from indirect observations, such as fish peeling line off a reel during sport fishing, which are difficult to verify under controlled conditions.
Recent direct measurements using animal-borne bio-loggers provide a different perspective on routine movement. Data collected from these tracking devices show the mean cruising speed is much lower, typically around 2 miles per hour (3.24 km/h). The maximum burst speed directly recorded by these loggers was approximately 11 miles per hour (18 kph). This discrepancy highlights the difference between sustained swimming and the unverified, brief escape or attack speeds that contribute to the Mako’s fame.
The Shortfin Mako is the species that holds the speed record among all sharks, allowing it to pursue swift prey across vast distances. The difficulty in measuring true peak speed in the wild means the Mako’s ultimate velocity remains a subject of ongoing debate.
Physiological Blueprint for Extreme Speed
The Shortfin Mako’s extraordinary speed is a result of several highly evolved biological and physical adaptations. Chief among these is its ability to regulate internal temperature, a trait known as regional endothermy. Like other sharks in the Lamnidae family, the Mako possesses a specialized network of blood vessels called the rete mirabile, or “wonderful net.” This counter-current heat exchange system warms the blood returning to the core muscles, eyes, and brain.
This internal warming enhances the power output of the swimming muscles, allowing them to contract with greater force and speed regardless of ocean temperature. The Mako’s body is designed for efficiency, featuring a sleek, fusiform shape that minimizes drag. Its skin is covered in tiny, tooth-like scales called dermal denticles, which help control water flow and reduce friction.
Propulsion comes from a lunate, or crescent-shaped, caudal fin, which is highly efficient for generating thrust. The powerful swimming relies on internalized red muscle, kept warm by the rete mirabile, fueling continuous, high-performance movement. This high metabolic rate demands a constant oxygen supply, forcing the shark to employ ram ventilation, meaning it must swim continuously with its mouth slightly open to force water over its gills.
Mako Sharks in the Oceanic Speed Hierarchy
While the Shortfin Mako is the fastest shark in the ocean, its position in the overall oceanic speed hierarchy is less clear. The Mako’s top speeds, commonly cited around 46 mph, make it faster than other large predators like the Great White shark. However, it faces stiff competition from certain bony fish that specialize in extreme bursts of speed.
The title of the fastest fish is typically awarded to billfish, specifically the Sailfish or the Black Marlin. The Sailfish is frequently credited with speeds up to 68 miles per hour (110 km/h), while the Black Marlin has estimates reaching 82 miles per hour (132 km/h). These extraordinary figures, similar to the Mako’s highest unverified claims, are often based on observations of how quickly they strip fishing line, leading to scientific skepticism.
Other pelagic speedsters, such as Wahoo and Yellowfin Tuna, are also consistently ranked among the fastest fish, capable of bursts up to 57 miles per hour (91 km/h). The physical limits of water resistance and cavitation suggest that the highest speeds attributed to both the Mako and the billfish may be physically impossible. The Mako is generally considered the second or third fastest fish overall, but the true maximum speeds of all these oceanic racers remain subject to the limitations of in-water measurement.