A mako pup begins its life inside its mother. Mako pups are born alive, and they have no placental connection to their mother, so they are nourished by egg yolk before birth. Mako embryos hatch inside the mother and feed on unfertilised or less developed eggs, a habit called oophagy. A pup grows inside its mother for 15 to 18 months before it is born.
When the pups arrive, they arrive in numbers. A litter can hold from 4 to 25 pups, and a newborn pup is about 60 to 70 centimetres long. Makos are born looking like very small adults, and the mother gives them no care after birth.
Growing up takes many years. Female makos are not adults until about 18 years old, but males mature younger, at around 7 to 9 years. A female mako has a litter about every three years. How can scientists know how old a mako is? Age can be estimated from growth bands in a mako's backbone. It was once thought two bands formed each year, but recent work shows only one, so makos live about twice as long as once thought: shortfin makos are estimated to live about 29 to 32 years.
How fast can a mako swim? As of November 2026, the shortfin mako is considered the fastest shark in the world, and scientists think it can swim faster than any other shark or ray. Yet few direct speed measurements have been reported. In a 2023 study, tags worn by two free-swimming makos measured their swimming speed directly. The two makos cruised at an average speed of 0.90 metres per second, and the fastest burst the tags recorded was 5.02 metres per second, from a female mako 2 metres long. The tags also recorded a burst that lasted 14 seconds, at an average speed of 2.38 metres per second. The study found that makos generally cruise at speeds similar to other warm-bodied fish, and faster than sharks that do not warm their bodies, and the highest burst speed was among the highest ever directly measured in sharks, tunas and billfishes.
Following a mako through its life takes tags. Plastic dart tags show where a mako was tagged and where it was caught again, but they do not show when it moved, how long it took or the route it followed. Other tags send their data by satellite. Tags on a roughly seven-foot female mako showed she followed similar courses into the Pacific and back to the California coast over three years in a row. Waters off Southern California are a nursery area, and tagged makos returned there each year, most often in summer.
Words to know
- oophagy: eating eggs
- embryos: unborn animals
- nursery: place for young
- satellite: orbiting machine
