In the summer of 2007, rare sightings of blue whales were being reported by local boaters in the Los Angeles area, particularly mariners sailing on the much beaten path to Catalina Island.

Far and away the largest animal in the world, in fact, the largest animal to ever roam the planet, the blue whale was previously rarely seen south of the Central California coast. The Channel Islands have long been fertile grounds for this endangered species due to the abundance of krill, the blue’s main food source, but now the whales are consistently popping up around the Palos Verdes-point down to Long Beach during the summer months.

What was once a perplexing aberration now seems to have become a regular pattern, but the scientific community still has mostly unanswered questions about the whales’ appearances. There has yet to be any exhaustive research published, so for now, experts offer only educated speculation.

“Nothing that I’ve seen yet points to why,” said Rob Mortensen, bird and mammal assistant curator from the Aquarium of the Pacific in Long Beach. “Except the krill. It’s largely supposition on our part, but it’s because the krill has moved to this area…why the krill has moved here is what we’re a little bit confused by.”

With so little research on the behavior of krill in this area Mortensen also admits it’s possible the little crustaceans have always been around, and it’s a growth in whale population that’s pushing the large animals here from more northern areas.

“Since most of the whales are up north, south is the place where they could go to not compete with other whales for food,” says Mortensen.

Whatever the case, Mortensen and others believe that blue whales will probably be seen in this area for the foreseeable future as their presence doesn’t appear to be connected to any radical shift in climate, water temperature, food disappearance or man-made disruption.

For local boaters, this means summer-time whale watching n an opportunity to see a species that was hunted to the brink of extinction and are now slowly coming back. We are fortunate, as this area contains what is believed to be the largest concentrated population of blues in the world n somewhere between 2,000-3,000 individuals from a total world population of 15,000. And now that they seem to have found a new feeding ground, viewing these incredible animals is very possible.

While Mortensen and crew have occasionally been skunked in trying to track and view the whales, mostly they are successful.

From Long Beach they travel about seven or eight miles north and look for topography that suggests upwelling, which stirs up krill, making for simple and abundant feeding for the whales. This upwelling occurs near underwater shelves, so blues will sometimes be in areas that are in deep water not far from a shelf. The time of day doesn’t seem to be a factor.

“When the water’s coming up from a deeper depth, because of the upwelling, it’s bringing all the nutrients, krill and smaller fish with it n that’s what they’re actually looking for,” says Mortensen.

Now is the time to head 10 or 11 miles south of Marina del Rey to spot blues because soon they will be moving on to warmer waters. The migration, like many aspects of blue whale understanding, is not completely understood. It’s believed that the whales in this part of the world move south as the cooler months approach, but as with many pelagic species there are exceptions.

Unlike grey whales that are almost set to a predefined schedule and location, blues act differently. Science aside, for the purpose of an afternoon whale watch, come September, blue whales off the Palos Verdes coast will, in all likelihood become considerably more illusive.