Shortfin mako sharks are pursuit predators that feed primarily on bony fish and, to a lesser extent, squid. The exact species they target shifts depending on what ocean basin they inhabit, but the pattern is consistent: fast, open-water fish dominate the menu. In the northwest Atlantic, bluefish alone can account for more than three-quarters of stomach contents by volume, while in the northeast Atlantic, a slender surface fish called the Atlantic saury takes that role. What makes the mako’s diet interesting, though, goes beyond a simple prey list. Their warm-blooded physiology, extreme speed, and willingness to occasionally tackle prey as large as dolphins all point to a feeding strategy unlike that of most other sharks.
The Core Diet Across Oceans
Mako sharks are pelagic, meaning they live and hunt in open water rather than along the seabed. Their diet reflects that habitat. Studies that examine stomach contents consistently find teleosts (bony fish) as the dominant prey, with cephalopods like squid filling in as a secondary food source. But the specific fish species change depending on geography.
In the northwest Atlantic, one classic study found teleost remains in about two-thirds of mako stomachs, with bluefish making up roughly 78% of the diet by volume. Bluefish are themselves aggressive, fast-swimming predators, and the fact that makos rely so heavily on them says something about the shark’s hunting ability. Bluefish were the major inshore food item, suggesting that makos move toward the coast to exploit seasonal bluefish concentrations.1Canadian Journal of Fisheries and Aquatic Sciences. Food, Feeding Habits, and Estimates of Daily Ration of the Shortfin Mako (Isurus oxyrinchus) in the Northwest Atlantic
In the northeast Atlantic off the Iberian Peninsula, the picture looks quite different. There, the Atlantic saury makes up about 87% of the teleost prey and roughly 72% of all prey found in mako stomachs. Researchers examining those stomachs also found something unusual: some prey fish were missing their heads, their tails, or both, suggesting the sharks had bitten off and discarded those parts or that the prey was consumed in pieces during high-speed pursuit.2PubMed Central. Unexpected Headless and Tailless Fish in the Stomach Content of Shortfin Mako Isurus oxyrinchus
This geographic variability is not surprising for a wide-ranging predator. Makos follow the food that is locally abundant, and their diet essentially functions as a snapshot of whatever fast-swimming bony fish dominate their current patch of ocean.
When Makos Hunt Dolphins
One of the more striking findings in recent mako research is that these sharks do, on occasion, eat marine mammals. For a long time, researchers assumed that any dolphin tissue found in a mako stomach was scavenged from a carcass. That assumption is increasingly being challenged.
A study examining 96 non-empty mako stomachs from the northeast Atlantic found that six juveniles had consumed marine mammals. DNA analysis identified the remains as short-beaked common dolphins and possibly striped dolphins. The dolphins consumed were juveniles, but some were nearly as large as the sharks that ate them.3Marine Ecology Progress Series. DNA evidence of the consumption of short-beaked common dolphin Delphinus delphis by the shortfin mako shark Isurus oxyrinchus
More recent work has pushed the evidence further toward active predation rather than scavenging. Researchers documented dolphin remains (from Indo-Pacific bottlenose dolphins and clymene dolphins) in the stomachs of three large makos, and in at least one case, premortem bite marks supported the conclusion that the shark had attacked a living dolphin. That study noted the find was the first record of clymene dolphins in any mako diet, highlighting how opportunistic these sharks can be.4PubMed Central. Do shortfin mako Isurus oxyrinchus hunt dolphins actively?
A separate observation recorded a shortfin mako circling a finless porpoise that had a damaged tail fin. Bite marks on the porpoise’s head strongly suggested the shark had attacked it, and the timing of the injuries hinted at a multi-stage hunting approach: wound the prey first, then circle back. While makos primarily feed on small fish and cephalopods, findings like these suggest they prey on live cetaceans more often than previously assumed.5PubMed Central. A shortfin mako shark circling a finless porpoise with damaged caudal fin
This does not mean dolphins are a staple. They remain a rare and opportunistic part of the diet, likely taken when a vulnerable individual presents itself. But the evidence has shifted enough that researchers now treat active dolphin predation as a real, if uncommon, behavior rather than dismissing all such stomach contents as scavenging.
How Diet Shifts as Makos Grow
Like many predators, makos do not eat the same things at every life stage. Small juveniles target smaller prey, and adults expand into larger or different food sources. The details, however, are more nuanced than a simple small-prey-to-big-prey progression.
Stable isotope analysis from temperate eastern Australia found that nitrogen isotope values actually decreased with increasing body size, while carbon isotope values increased. In plain terms, larger makos appeared to feed more frequently on prey from lower positions in the food web, not higher ones as you might expect.6PubMed. Ontogenetic and spatial variation in the trophic ecology of the shortfin mako shark (Isurus oxyrinchus) in temperate eastern Australia This could mean bigger makos shift toward eating more abundant, smaller schooling fish rather than chasing the largest prey available.
Interestingly, research from the northern Mexican Pacific found somewhat different results: there, mako muscle tissue was enriched in the nitrogen isotope as body size increased, which would be consistent with larger sharks eating at a higher trophic level. The authors cautioned that habitat differences between inshore and offshore waters could confound the pattern.7Fisheries Oceanography. Tissue‐specific stable isotope ratios of shortfin mako (Isurus oxyrinchus) and white (Carcharodon carcharias) sharks as indicators of size‐based differences in foraging habitat and trophic level
The apparent contradiction likely reflects different regional ecosystems. In waters where big schooling fish like sardines or saury are abundant, a large mako may fill up efficiently on huge quantities of lower-trophic-level prey. In other regions, the most abundant food for a big shark might be medium-sized predatory fish, which sit higher on the food web. The takeaway is that mako diet is flexible and opportunistic: body size opens up new possibilities, but local prey availability drives what actually ends up in the stomach.
Built to Eat Fast
The mako’s diet makes more sense when you understand its physiology. Shortfin makos are among the very few sharks that maintain elevated body temperatures, a trait called regional endothermy. They can keep their muscles, eyes, brain, and even their viscera warmer than the surrounding water. This has direct implications for how they hunt and how quickly they process food.
Makos are considered capable of the highest swimming speeds of any shark and potentially carry one of the highest energetic demands of any marine fish. Researchers who directly measured swimming speeds recorded burst events reaching about 3.7 meters per second, with those bursts almost always directed downward and occurring during daylight hours.8PubMed Central. First insights into the shortfin mako shark (Isurus oxyrinchus) fine-scale swimming behaviour The downward orientation of attack bursts aligns with a pursuit strategy: dive fast toward prey below, using gravity and speed together.
That speed carries a metabolic cost. Estimates of routine field metabolic rate put the mako at about 185 mg of oxygen consumed per kilogram per hour at 18°C. That is a substantial energetic demand, and it means makos need to eat frequently to keep fueled.9PubMed Central. Direct measurement of cruising and burst swimming speeds of the shortfin mako shark (Isurus oxyrinchus) with estimates of field metabolic rate
To meet that demand, makos have a digestive edge. Because they keep their guts warm, their digestive enzymes work faster than those of cold-bodied sharks. When researchers compared digestive enzyme activity in makos against blue sharks and thresher sharks, makos showed significantly higher activity for gastric pepsin, pancreatic trypsin, and lipase at their normal body temperatures. Even when tested at the same temperature, mako trypsin still outperformed the blue shark’s, and mako enzyme activity across the board beat the thresher shark’s. The practical result is faster food processing: a mako can break down a meal and be ready to hunt again sooner than a cold-bodied shark of similar size.10PubMed. Digestive enzyme activities are higher in the shortfin mako shark, Isurus oxyrinchus, than in ectothermic sharks as a result of visceral endothermy
Competing With Blue Sharks and Swordfish
Makos do not hunt in a vacuum. The open ocean is shared with other large predators that target similar prey, and how these species divide resources matters for understanding mako feeding ecology.
In the Mediterranean and northeast Atlantic, shortfin makos showed more than 80% isotopic niche overlap with blue sharks, meaning the two species feed on broadly similar prey. Blue sharks tend to rely more heavily on squid, while swordfish lean more toward fish, but the overlap between all three predators is considerable. The research found that the potential for competition within a species was lowest for makos, suggesting they are more flexible in spreading out their individual diets and avoiding head-to-head competition with each other.11PubMed Central. Pelagic productivity and abundance of competitors modulate trophic niche segregation between large predators
When resources are plentiful, the overlap between these predators actually increases: there is enough food for everyone, so the incentive to specialize shrinks. When productivity drops, the species partition resources more strictly. This finding suggests mako diet flexibility is partly an ecological response to who else is at the table.
In the northeast central Pacific, however, the picture was different. There, makos and blue sharks did not overlap isotopically with tuna and billfish, unlike other pelagic shark species that did. This hints that makos and blue sharks occupy a somewhat distinct feeding niche in that region, possibly using different depth zones or prey patches than large bony predators.12Journal of Experimental Marine Biology and Ecology. Trophic interactions among pelagic sharks and large predatory teleosts in the northeast central Pacific
The Longfin Mako Difference
When people say “mako shark,” they almost always mean the shortfin mako. But there is a second species, the longfin mako, that lives a very different life and eats different things. Longfin makos are deeper-water animals, slower swimmers, and considerably rarer. They are listed as endangered, while the shortfin mako is listed as endangered as well but is far more commonly encountered.
Stomach content data from longfin makos is scarce simply because so few specimens are examined. One study from the tropical western Pacific found longnose lancetfish and squid in a longfin mako’s stomach, alongside, unfortunately, plastic debris including a polypropylene bottle cap and lollipop packaging.13Environmental Science and Pollution Research. Plastic ingestion and trophic transfer in an endangered top predator, the longfin mako shark (Isurus paucus), from the tropical western Pacific Ocean Lancetfish are deep-water predators themselves, which is consistent with the longfin mako’s deeper habitat. The plastic ingestion highlights a growing concern: as top predators, makos accumulate whatever contaminants their prey has already absorbed, and now they are ingesting synthetic debris directly as well.
Mercury and What a Mako’s Diet Means for the Food Web
Because makos sit near the top of the marine food web and eat other predatory fish, they accumulate contaminants at disproportionately high levels. Mercury is the best-studied example. A study of recreationally caught pelagic predators off southern New England found that mako sharks had the highest mercury concentrations of any species tested, averaging about 2.65 parts per million. That was roughly six times higher than yellowfin tuna and more than 13 times higher than dolphinfish from the same waters. Mercury concentration in sharks increased exponentially with both body size and trophic position.14PubMed. Trophic influences on mercury accumulation in top pelagic predators from offshore New England waters of the northwest Atlantic Ocean
The majority of fish in that study exceeded the U.S. EPA’s recommended mercury limit, and makos exceeded it by the widest margin. A separate study examining mercury in four shark species off Baja California confirmed the same bioaccumulation pattern in mako muscle tissue.15PubMed. Bioaccumulation and biomagnification of total mercury in four exploited shark species in the Baja California Peninsula, Mexico
For anyone who catches and eats mako, this is the most practical dietary fact about the species. The same feeding strategy that makes them fascinating predators — eating large, predatory fish at high trophic levels, processing food quickly, growing to large sizes — concentrates mercury and other pollutants in their flesh at levels well above what health agencies consider safe for regular consumption.
How Researchers Piece Together a Shark’s Diet
Understanding what a mako eats is harder than it sounds. Stomach content analysis is the most direct method: catch a shark, examine what is inside. But this only tells you about the last meal or two, and many sharks are caught with empty stomachs. Prey items are often partially digested and unrecognizable, which is exactly why the northeast Atlantic dolphin study relied on DNA sequencing to identify those mammal remains that could not be identified visually.3Marine Ecology Progress Series. DNA evidence of the consumption of short-beaked common dolphin Delphinus delphis by the shortfin mako shark Isurus oxyrinchus
Stable isotope analysis provides a longer-term view. The ratios of carbon and nitrogen isotopes in a shark’s tissues reflect what it has been eating over weeks to months, depending on the tissue sampled. Muscle integrates diet over a longer window than blood, which is why some studies sample both. This approach reveals dietary patterns that stomach contents alone would miss, like the size-based trophic shifts described earlier. The tradeoff is that isotope data tells you where in the food web a shark feeds but cannot name specific prey species.
Newer techniques like DNA metabarcoding, which sequences trace genetic material from gut or cloacal samples, promise to bridge that gap by identifying prey species even from digested remains. As these tools become more accessible, the picture of mako feeding will likely get richer. Even now, though, the broad strokes are clear: makos are fast, flexible predators whose diet is built around bony fish, supplemented by squid, and occasionally expanded to include surprisingly large prey when the opportunity arises.