A mating pair of wolf-eels laid a mass of eggs at Birch Aquarium at Scripps in December. It was the first spawning by that particular pair of wolf eels,which came to the aquarium in 2009 from the Oregon Coast Aquarium, and the third batch of wolf-eel eggs laid at the aquarium since it opened in 1992.
Over the next several weeks, aquarists cared for the eggs behind the
scenes, replicating ideal conditions in the wild as closely as possible. They began to hatch in late March.
Wolf-eels (Anarrhichthys ocellatus) look rather like true eels in shape,
with long grey bodies and big blackspots. These eel-like fish have big heads with large jaws and teeth. Wolf-eels can grow several feet long, and they have powerful jaws that give them an amazing ability to crush their prey. Their strong teeth and mouths can withstand the spines of large sea urchins and the shells of crabs and snails.
These animals are found in the Pacific Ocean from Japan to Alaska and all the way down to Southern California. They are found in sub-tidal areas of the cold Pacific Northwest, but can live up to 700 feet deep in warmer waters. The juveniles live close to the surface in the pelagic zone, forming part of the zooplankton for approximately their first two years of life. As wolf-eels grow bigger, they look for nooks and crevices to inhabit on the bottom of the ocean.
By four years of age, wolf-eels find a partner and are thought to mate for life. They are mature enough to breed at about seven years. The female lays several thousand eggs and wraps her body around them to form an almost translucent mass that is bigger than a baseball. The wolf-eel couple guards the eggs fiercely.
After about three months, the eggs hatch and start their life independent of their parents in the open ocean.
Photos courtesy Birch Aquarium at Scripps