A dark oily band off the coast of La Jolla has been causing people to worry over the last few days. But, it turned out there was nothing to worry about. The band consisted of millions of northern anchovy feeding off plankton in the area. It is the largest band of this species seen in the area in over 30 years.
Northern anchovy, one of many species in the Engraulidae family marketed as “anchovies,” are rarely seen in warmer waters. The water temperature off the coast of La Jolla was estimated to be about 74 degrees yesterday. It is unknown exactly why the fish has decided to visit the area at this time, but food availability is likely the reason. Anchovies are a commercially harvested fish off the coast of California and are frequently used as bait or for fish meal for animal feed. In the past, northern anchovies were also heavily used for human consumption as well as its oils.
Anchovies are an integral part of the food chain. Many marine animals and birds rely on them, including sharks and other large fish. The large shoal is good news for the thousands of elegant terns that are nesting in the county. They’re also good news for the California brown pelicans whose young should be getting close to fledging at this time. Those young pelicans will soon be dispersing from the Gulf of California where most of the population breeds. Many young pelicans frequent the coast off of San Diego during their first months learning to find food.
Scientists at the Scripps Institution of Oceanography have collected samples from the shoal for further study. It is unknown how long this shoal will remain in the area. There is no danger to human swimmers from the anchovies, except that they may attract predators, such as sharks, to the area. The anchovies may also attract seals and other animals that sharks prey on. Swimmers and kayakers should take precautions while in the water near the fish.