Massive Northern Anchovy School in California is the Largest in 30 Years (VIDEO)

On July 8, a massive school of anchovies formed off of the coast of California. Located off La Jolla, the school is the largest seen in 30 years.

According to scientists at the Scripps Institution of Oceanography at the University of California, Sand Diego, the massive school is unusual. It's currently unclear why the school of Northern Anchovy moved into shallow waters off the coast, but members of the Scripps Marine Vertebrate Collection have now collected samples for study.

Northern Anchovy is a commercial species that's usually harvested off the West Coast. It's usually used as bait in other fisheries and is sometimes processed into fish meal. Yet in days gone by, this species once supported a multimillion-dollar fishery since the catch was sold for human consumption, bait, and reduction into meal, oil and soluble protein.

In fact, this species was fished off the West Coast since at least 1916. Yet this fishery eventually collapsed in the 1940s and 1950s after the fish were overharvested due to the beginning of the canning industry. Eventually, consumer demand for anchovies faded as sardines came back.

The recent school of anchovies so close to shore may not be due to fisheries, though, but rather may be due to the weather.

"It certainly is a mystery, but it may have something to do with the impending El Nino," said David Checkley, Scripps professor, to the Huffington Post. This weather system could have caused the fish to change their usual behaviors as they responded to the varying temperatures.

When the school appeared, researchers, graduate students and the simply curious flocked to see the anchovies. They took pictures of the massive school and some even videoed the event.

Want to see more? Check out the video below of the massive school of anchovies migrating off of La Jolla, courtesy of Scripps University.