Swordfish are some of the fastest, most powerful hunters in the ocean. It is hard to square that with this photo, where a baby swordfish sits comfortably on the tip of one finger. It truly is one of the strangest looking animals, and undeniably adorable.
What does a baby swordfish look like?
Tiny, spiky and already armed. Swordfish hatch at about 4 millimeters long, with a short snout, prickly scales and a mouth full of small teeth. The famous sword is well developed by the time they reach about a centimeter.
The photo comes from fisheries biologist Juan C. Levesque, who shared it in a 2014 feature on the swordfish life cycle, crediting marine biologist Jay Rooker. Rooker’s lab at Texas A&M University at Galveston studies young swordfish in the Gulf of Mexico.
Baby swordfish look very little like their parents. Adults (Xiphias gladius) are sleek, smooth and dark blue-black. The larvae are freckled with orange, bristling with rough scales, and armed with teeth that the adults lose entirely. It is one of those animals that seems to redesign itself completely on the way to growing up.
How fast do baby swordfish grow?
Remarkably fast. The larvae can add an eighth to a quarter of an inch a day, and by their first birthday young swordfish average about a meter (39 inches) from eye to tail fork. Adults can pass 4.5 meters, and the heaviest on record top 650 kilograms. Females grow faster and larger than males, and almost every giant is a female.
To keep up their numbers, females release enormous amounts of eggs, each only about 1.6 to 1.8 millimeters across. Estimates run from about 1 million to as many as 29 million in a season for a large female. In the Atlantic, much of the spawning happens in spring in the warm southern Sargasso Sea, and off Florida it runs through the year, peaking from April to July.
To bring this amazing animal home, you can customize swordfish-shaped personalized keychains, encapsulating the swordfish’s agility and majesty in the palm of your hand.
For more of the ocean’s odd designs, see our guide to animal defense mechanisms, meet the Wookiee of the deep sea, or read why hammerhead sharks matter.
