The shortfin mako shark is a highly migratory pelagic species found in temperate and tropical oceans around the world[1]. Like all members of the Lamnidae family, which also includes the white shark and porbeagle shark, it is regionally endothermic (warm-blooded), enabling it to maintain elevated body temperatures and sustain remarkable speed and activity levels even in cold northern waters.

Capable of reaching speeds of up to 75 km/h (46 mph), the shortfin mako is widely regarded as the fastest shark and among the fastest fish in the world. Its streamlined, torpedo-shaped body, powerful crescent-shaped tail, and highly efficient musculature make it an exceptionally agile predator adapted for pursuing fast-swimming prey such as tuna, mackerel, and squid in the open ocean.

In Atlantic Canada and Québec, the shortfin mako is an occasional visitor and is sometimes confused with the white shark (Carcharodon carcharias) or the porbeagle shark (Lamna nasus), particularly due to its similar body shape and large triangular dorsal fin. However, the mako can generally be distinguished by its more slender body, longer pointed snout, larger eyes, and distinctly crescent-shaped tail.

(1) Jensen, C., L. Natanson, H.L. Pratt Jr, N.E. Kohler, and S.E. Campana. 2002. The reproductive biology of the porbeagle shark (Lamna nasus) in the western North Atlantic Ocean. Fishery Bulletin 100(4):727-738.

The shortfin mako shark is a seasonal visitor to much of the Gulf of St. Lawrence, particularly its eastern and deeper offshore regions, but it is not known to enter the St. Lawrence Estuary. Most observations occur during the warmer months, when the species follows concentrations of pelagic prey such as mackerel, tuna, and squid into Atlantic Canadian waters.

The timing and duration of the mako’s seasonal presence in the Gulf may be influenced by changing ocean temperatures and shifting prey distributions associated with climate change.

According to the Canadian Shark Attack Registry, there are no confirmed incidents involving shortfin mako sharks (Isurus oxyrinchus) and humans in Canadian waters. Although the species is an exceptionally fast and powerful pelagic predator, it primarily feeds on schooling fish, squid, and other fast-moving prey and rarely comes into contact with people in Atlantic Canada.

Elsewhere in the world, shortfin makos have occasionally been implicated in incidents involving fishers, spear fishers, and baited situations at sea. The species is known for its speed, strength, and highly energetic behaviour, particularly when hooked or stimulated by struggling prey. Recreational shark fishers frequently describe makos leaping violently from the water during capture attempts.

Despite this reputation, interactions with humans remain extremely uncommon in Canadian waters and are not considered a significant public-safety concern under normal circumstances.

(1) Gallant, J. (2022. July 26). Canadian Shark Attack Registry (1st ed.). St. Lawrence Shark Observatory.

The shortfin mako shark is occasionally caught as by-catch in offshore pelagic fisheries targeting tuna and swordfish in Atlantic Canada. Historically, the species was also sought by some recreational shark fishers and occasionally landed during Atlantic shark derbies and tournaments, particularly in Nova Scotia. In recent years, however, increased conservation concerns and tighter regulations have greatly reduced the retention of shortfin makos in Canadian waters.

Despite its speed and wide-ranging distribution, the shortfin mako shark is highly vulnerable to overexploitation because of its relatively slow growth, late maturity, and low reproductive rate. The species has experienced major population declines in several parts of the Atlantic as a result of commercial longline fisheries and international demand for shark meat and fins.

The shortfin mako shark (Isurus oxyrinchus) is currently listed as Endangered by COSEWIC (Committee on the Status of Endangered Wildlife in Canada) because of substantial population declines associated with international fishing pressure and by-catch in pelagic longline fisheries. The species is also listed under Canada’s Species at Risk Act (SARA), making it illegal to intentionally capture, harm, or retain shortfin makos in Canadian waters except under specific exemptions.

Globally, the shortfin mako shark is classified as Endangered by the International Union for Conservation of Nature (IUCN). The species has experienced major declines throughout much of its range because of intensive fishing pressure for meat, fins, and sport fishing. Its slow growth, late maturity, and low reproductive output make recovery particularly difficult once populations decline.

In Atlantic Canada, shortfin makos are encountered primarily as by-catch in offshore fisheries targeting tuna and swordfish. Because the species is highly migratory and crosses international boundaries, its long-term conservation depends heavily on coordinated international fisheries management and enforcement.