Q: My dive buddy and I are debating what THE fastest creature in the sea is. He thinks it's a killer whale, I think it's a mako shark. Since you're so all-knowing, maybe you could settle this little bet for us: what is the fastest animal in the sea, and how do they measure the speed? There's a mondo pizza on the line in all this.
Long Beach, NY
A: Just about everyone who spends time on, in, or under the sea has his own candidate for speed champion of the ocean. Big game fishermen vote for the Marlin, Swordfish, Bluefin Tuna, or Wahoo; shark enthusiasts vote for the Shortfin Mako; small whale scientists favor the Spotted Dolphin, Dall's Porpoise, or Killer Whale; proponents of the 'maximum horsepower' school incline toward the great rorquals — the Blue, Fin, or Sei Whales. But speed in the water is extraordinarily difficult to measure, and most debates quickly degrade to heated speculation or run aground for lack of reliable data.
Water is a very dense medium — about 750 times that of air — and requires enormous power to move through quickly. The physics of swimming is rather complicated, heavy and opaque with symbol-dense mathematics. Fortunately, we don't have to mess with that here (>Whew!<). Factors affecting an organism's speed through the water include: overall size and shape; the nature, size and shape of propulsive organs (siphon, fins, flukes); the type of muscle powering these organs and the conditions under which they operate. See the accompanying sidebar, 'Factors Affecting Speed in Water', for more details.
The accompanying table shows the maximum speeds measured or reliably reported for a variety of marine life. Unless indicated otherwise, the figure listed is underwater swimming speed in miles per hour (mph). Wherever possible I have erred on the side of caution, since in most cases a precise, measured course and method of controlling the speed trials or participants was not available at the time the data were recorded.
Maximum Travel Speed of Selected Marine Life
Species (Scientific Name),
Mode of Travel
[if other than swimming]
|Abalone (Haliotis), crawling||0.012|
|Goby (Gobius minutus)||0.6|
|Rock Gunnel (Pholis gunnelus)||0.7|
|Sprat (Clupea sprattus)||1.4|
|Stickleback (Spinachia spinachia)||1.75|
|Flounder (Pleuronectes flesus)||2.4|
|Eel (Anguilla rostrata)||2.4|
|Plaice (Pleuronectes platessa)||2.9|
|Herring (Clupea harengus)||3.6|
|Human (Homo sapiens)||5.04|
|Sea Trout (Salmo trutta)||5.4|
|Pacific Salmon (Oncorhynchus)||8|
|Mackerel (Scomber scombrus)||12|
|Pacific Salmon (Oncorynchus), leaping||14|
|Gentoo Penguin (Pygoscelis papua)||17|
|Bottlenose Dolphin (Tursiops truncatus)||17|
|Pacific Whitesided Dolphin (Lagenorhynchus obliquidens)||17|
|Mahi Mahi (Coryphaena hippurus)||20|
|Market Squid (Loligo opalescens)||20|
|Leatherback Turtle (Dermochelys coriacea)||22|
|Common Dolphin (Delphinus delphis)||23.6|
|Blue Shark (Prionace glauca)||24.5|
|Pacific Spotted Dolphin (Stenella attenuata)||24.7|
|California Sea Lion (Zalophus californianus)||25|
|Fin Whale (Balaenoptera physalus)||25.42|
|Blue Whale (Balaenopterus musculus)||29.76|
|Shortfin Pilot Whale (Globicephala macrorhynchus)||30.4|
|Shortfin Mako (Isurus oxyrinchus)||31|
|Dall's Porpoise (Phocaenoides dalli), leaping||34.5|
|Killer Whale (Orcinus orca)||34.5|
|Flying Fish (Exocoetidae), gliding||35|
|Mahi Mahi (Coryphaena hippurus), leaping||37|
|Bonito (Sarda), leaping||40|
|Albacore (Thunnus alalunga), leaping||40|
|Blue-fin Tuna (Thunnus thynnus), leaping||43.4|
|Yellowfin Tuna (Thunnus albacares), leaping||46.35|
|Wahoo (Acanthocybium solandri), leaping||47.88|
|Marlin (Makaira), leaping||50|
|Swordfish (Xiphias gladius), leaping||60|
|Sailfish (Istiophorus platypterus), leaping||68|
Measuring the speed of a marine animal against the known velocity of a boat or ship has long been a popular method, but one which is fraught with difficulties. For centuries, it was thought that dolphins could swim faster than ships, hence their ability to overtake the fastest vessels and remain in front of them. We now know that a pressure wave is created in front when a ship moves through water, enabling dolphins to be pushed forward and surf-ride the slope of a breaking bow wave.
Because they are easily captured and trained, dolphins have been clocked over measured distances and their actual speeds recorded. The 17 mph record for the Bottlenose Dolphin is based on U.S. navy tests of captive individuals and is probably accurate. The fastest dolphin recorded during U.S. Navy trials was for a more slender species, the Pacific Spotted, whose maximum sprint speed of 24.7 mph. The Dall's Porpoise — a chunky, hyperactive speed demon of the North Pacific — is believed to be even faster (speeds up to 34.5 mph have been reported), but since it does not fare well in captivity, it has not been trained or its speed measured.
Most large sharks are cold-blooded and cruise at a leisurely 1.5 mph. Because most species fare poorly in captivity, the maximum swimming speed of a shark has seldom been measured. The Blue Shark is an open ocean glider, planing on wing-like pectoral fins and flattened belly. There exists a dubious record of a small Blue Shark about two feet in length which was found to swim steadily against a current at 17.7 mph and was reported to achieve 43 mph in short bursts. The most reliable record of a Blue Shark at speed is 24.5 mph for a 6.5-foot-long individual.
The Shortfin Mako is an open ocean sprinter, with a highly streamlined body, a lunate tail supported by keels, a sharply pointed snout, large eyes and some of the wickedest-looking teeth in sharkdom. Like the Great White and a few of its lamnoid relatives, the Shortfin Mako has a jury-rigged circulatory system which enables this species to retain metabolic body heat, making it functionally warm-bodied. The Mako is a spectacular game fish, often leaping repeatedly when hooked. Calculations show that for a Shortfin Mako to leap 15 to 20 feet into the air, a velocity of 22 mph is required — and this for a shark impeded by the drag of a fishing line trailing from its mouth. Underwater, a Shortfin Mako has been reliably clocked at 31 mph, and there is one claim that it has a burst swimming speed of up to 46 mph. Not surprisingly, Shortfin Makos are able to catch even the fastest of fishes — there is a record of a 750-lb Mako with a whole 120-lb Swordfish in its stomach; however, it is uncertain whether the shark out-sprinted or out-maneuvered the Swordfish.
Tunas and mackerels, collectively termed 'scombroids', are fast-swimming open-ocean predators with torpedo-shaped bodies, fins that fold into recesses on the body, narrow tail stalks with horizontal keels, and deeply forked tails. Scombroids typically cruise in packs at about 9 mph in search of shoals of sardines; a 15 year old tuna would have traveled something like 1.2 million miles in its lifetime. Many tunas are warm-bodied endurance swimmers, beating their tails up to 20 times a second for hours or even days on end.
Some big-game anglers believe that the Bluefin Tuna is the fastest fish in the sea. Burst speeds of up to 64.4 mph have been claimed for this species, but the highest speed recorded so far is 43.4 mph in a 20-second dash. The Yellowfin Tuna and the Wahoo (great name for a superfast gamefish, innit?) are also extremely fast, having been timed at 46.35 mph and 47.88 mph, respectively.
Other big-game fishermen favor the billfishes, including Swordfish (family Xiphiidae), marlins and the spectacular sailfishes (family Istiophoridae). There is no doubt that these fishes are capable of tremendous speeds, at least in short bursts, and many of them also leap. But here again, the practical difficulties of measuring speed in the water make reliable data extremely difficult to secure. The 60 mph figure listed for the Swordfish is based on a corrupted version of calculations made by Sir James Gray to estimate the impact speed necessary for a hypothetical 600-lb Swordfish to embed its sword 3 feet in the timbers of ships, as has been known to occur; the figure seems to have entered the literature without question as though someone had actually timed a Swordfish at speed.
The Atlantic Sailfish is considered by many to be the fastest species of fish over short distances. In a series of speed trials carried out at Long Key Fishing Camp, Florida, one Sailfish took out 100 yards of line in 3 seconds, which is equivalent to a speed of 68 mph. It is important to bear in mind, however, that the fish was leaping while its speed was timed, so this speed does not really represent swimming speed.
Whales are also known to be capable of prodigious speeds. Who could doubt a wide-eyed whaler's estimate of the hair-raising speed of his first 'Nantucket sleighride'? American naturalist Roy Chapman Andrews, writing of the Fin Whale, said it was "the greyhound of the sea ... for its slender body is built like a racing yacht and the animal can surpass the speed of the fastest ocean steamship." A recent study lists the maximum speed recorded for the Fin Whale at 25.42 mph, but this is not the fastest great whale. This honor seems to fall to the Blue Whale, a creature that has garnered numerous superlatives in the animal kingdom, including the title of 'largest animal that has ever lived'. The Blue Whale can reach a length of more than 100 feet and weigh upwards of 150 tons; to propel its vast bulk through the seas at 10 knots (11.5 mph) would require something like 520 horsepower. The Blue Whale has been recorded swimming at speeds up to 29.76 mph.
Other animals may be even faster than the Blue Whale, Spotted Dolphin, the Swordfish, or even the Shortfin Mako. The Killer Whale is the largest species of dolphin and one of the sea's paramount predators. Readers of the April 1979 issue of National Geographic will recall the extraordinary photos of a pack of Killer Whales attacking a 60-foot Blue Whale. The Blue may not have tried to outswim the Killers, or perhaps the pack-feeding strategies employed by these whales may have tired the Blue before the attack. Whatever provoked the attack, there can be no doubt that the Killers had caught and attacked the Blue. Killer Whales have also been recorded eating Gray and Minke Whales, seals, porpoises, other dolphins, bony fishes, penguins, sea turtles, and even sharks. In other words, the Killer Whale can — and does — catch anything that swims.
In the same study which recorded the speeds of the Fin and Blue Whales, the Killer Whale was clocked at only 22.94 mph. But the table in the study is captioned "maximum speed when alarmed". Blue and Fin Whales feed on krill and small fishes; they will turn and accelerate away when 'alarmed' by a whaler's catcher boat. But what can alarm a Killer Whale? They virtually ignore boats, communicating an almost pure sense of power and mastery over their element. In October 1958, a bull Killer Whale measuring an estimated 20 to 25 feet in length, was reportedly timed at 34.5 mph in the eastern North Pacific. There may be animals in the sea that can beat it in a one-on-one race, but there is no animal that can escape a hunting pack of Killer Whales.
I don't know which animal is the fastest in the sea. In absolute terms — if we allow leaping — the clear winner is the sailfish. Among underwater swimmers: for short sprints, I would go with the Shortfin Mako; for sheer horsepower, nothing comes close to the Blue Whale. But for the highly effective combination of speed, power, and endurance, I'd have to go with Orcinus orca, the Killer Whale. Pay up Fred!
In general, it is more energy efficient to propel a large body through a fluid than a small one. This is due (in part) to surface drag, in which a boundary layer of fluid 'sticks to' the surface of a creature and must be moved along with it; a large organism has relatively less surface area per unit volume than a small one — so for a small creature in seawater, the boundary layer must make swimming rather like plodding through molasses. Streamlining minimizes the amount of fluid that must be 'pushed out of the way' before a body can move forward and reduces drag due to turbulence as the fluid closes in behind a moving body. A smooth body tapered on both ends is generally best for this, although the rough scales of some sharks have been modified to reduce drag.
Forward propulsion depends on relatively straight-forward Newtonian principles, such as: lift must exceed weight, thrust must exceed drag, and thrust depends on 'action and reaction' (a swimming creature is pushed forward with the same force as water is pushed backward). Hydrofoil-shaped fins (flattened on the lower surface, rounded on the upper) create lift while the creature is moving above a fixed critical velocity (or 'stalling speed'). The fastest swimmers tend to have sickle-shaped fins or flippers, narrow tail stalks, and deeply-forked, lunate (crescent moon-shaped) tail fins or flukes, often intersected at right angles by fleshy keels; these qualities maximize thrust while minimizing drag. In an emergency (such as a Calamari Festival?), squids and other cephalopods rely on a kind of 'jet propulsion' to squirt water backward through a restricted opening (the siphon), thereby increasing thrust. Some fast-moving ocean rovers increase their overall speed by leaping, maximizing thrust against the water and minimizing drag through the air.
Type of swimming muscles and their operating conditions profoundly affect sustainability of swimming speeds. The physiology of muscle contraction is quite complex, but for our purposes we need only consider 'red' versus 'white' and 'warm-blooded' versus 'cold'. Red muscle is relatively slow-contracting and requires an oxygen-rich environment, but has terrific stamina; 'white' muscle is relatively fast-contracting, does not require an oxygen-rich environment, but has very little stamina. The swimming muscles of most fishes are predominantly white muscle — great in an acceleration emergency but tending to get 'pooped' rather quickly due to lactic acid build-up; many of the fastest fishes — mackerels, tunas, billfishes, and mackerel sharks — augment their swimming muscles with a band of red muscle along the flanks. Marine mammals rely primarily on red muscle for propulsion, but as air-breathers must continually surface to renew their supply of oxygen; so long as the oxygen supply is adequate, marine mammals are powerful sustained swimmers. Since muscle contraction is stronger and faster at higher temperatures, cold blooded creatures — such as squids, most sharks and bony fishes — are limited by their fast but low-stamina muscles. Marine mammals, conversely, are warm-blooded — able to maintain body temperature within a narrow range that is optimal for slower but more sustained swimming.
Credit Where Due: this article owes a large debt to a wonderful column by Richard Ellis, entitled "Speed in the Water" that I read many years ago in Sport Diver magazine (I think). Since the magazine is now defunct, I do not have a copy, and I read the article while staying at the house of a friend who has since passed away, I cannot properly cite it here. I should also acknowledge the always fun and encyclopedic Guinness Book of World Records, which was very useful in compiling the table.