Humpbacks call coast home … for now

For an ocean lover or wildlife enthusiast, there are few more thrilling sights than watching a pod of humpback whales frolicking up close.

This summer has been a banner year for humpback watching along the California coast, with many of the huge animals feeding and performing their acrobatic behavior unusually near shore. Marine biologists say these displays may be happening more frequently as a result of climate change.

Since June, the whales have been seen close to shore in multiple locations off San Luis Obispo County, including Avila Beach, Port San Luis, Diablo Canyon nuclear power plant, Cambria and San Simeon Cove.

The most reliable sighting has been a juvenile humpback that fed in San Simeon Cove for more than a month in July and August, mostly by itself but occasionally with other juveniles and adults with calves. The whale was seen feeding at various locations in and around the cove, sometimes swimming right next to the pier, much to the delight of throngs of sightseers.

Carl “Cubby” Cashen, owner of Sea for Yourself Kayak Outfitters in San Simeon said last week that he has seen the whale at multiple locations in and around San Simeon Cove, feeding constantly. The whale obviously found a large school of anchovies because he could see the fish jumping as the whale fed.

Dining on anchovies

Humpback whales are one of several whale species found along the Central Coast. An estimated 2,000 humpbacks feed in California waters during the summer and fall, then migrate in the winter to calving and mating areas off Mexico. They are readily recognizable by their extremely long and slender flippers, which they often raise well out of the water.

Humpbacks are what marine biologists call prey generalists, meaning they eat a variety of food. Their preferred food is krill, small shrimp-like animals that tend to be found offshore deep along underwater canyons and ridges, said Karin Forney, a research biologist with the National Marine Fisheries Service in Santa Cruz.

If krill are not available, the humpbacks will switch to baitfish, which along the Central Coast are mostly anchovies. Under the right wind and current conditions, the anchovies and whales can be just offshore.

“There has been a concentration of anchovies off of the Morro Bay coast, and the whales are foraging on those anchovies,” Forney said. “They come close to the shore when the food is there.”

Such near-shore humpback displays are uncommon. In recent years, there have been only been two such phenomena, said Steve McGrath, Port San Luis harbor manager.

This year, the whales were in the Avila Beach area for two weeks in June. In August 2012, they fed close to shore in Port San Luis for about 10 days.

“It absolutely amazes me how much food must be in the water here to sustain a dozen humpback whales for two weeks – it’s incredible,” McGrath said.

Dazzling displays

A spectacular whale display can cause traffic jams and other problems for the harbor district, particularly if pictures of the whales go viral on the Internet, which was the case in 2012. That year, the port was so thronged with whale watchers it took McGrath 45 minutes to drive from the harbor office to the other side of Avila Beach, a trip that would normally take mere minutes.

“It was gridlock,” he said. “We had to give up on enforcing parking regulations unless they were blocking traffic or otherwise endangering the public.”

In June, so many people packed the Avila Beach pier to watch whales that McGrath closed it indefinitely, concerned that the old structure might not be able to handle all the weight.

One reason why humpbacks are so popular with sightseers is that they display a variety of behaviors that are fun to watch. The most spectacular display is breaching, which occurs when a whale lunges into the air and splashes back down onto the water.

Other displays include surface feeding, spy-hopping, pectoral fin and tail slapping and tail lobbing. Scientists are not certain why humpback display such behavior, but they have several theories.

Tail and fin slapping could be a form of communication. Humpbacks tend to slap their tails when something is bothering them such as fishing nets and other foreign objects in the water, Forney said.

Spy-hopping is when a whale rises vertically out of the water and is thought to be a technique for the whale to view its above-water surroundings. Breaching could be a way to remove barnacles and parasites from the whales’ bodies, or they could do it just because it’s fun.

Keeping a distance

This varied behavior makes pods of humpback whales attractive to swimmers, kayakers and paddle boarders. However, getting too close to whales in the water is both dangerous and against the law, Forney said.

The Marine Mammal Protection Act of 1972 makes it illegal for boaters or anyone else on the water to harass whales or other marine mammals. This means getting close enough to a whale to cause it to alter its behavior, such as stopping feeding and swimming away.

“Stay at least 100 yards away,” Forney said. “That’s the closest you would ever want to get.”

Cashen said he rigorously enforces these rules in San Simeon Cove. Because the juvenile whale has been so active throughout the cove it has significantly reduced the area available for kayakers, and this has hurt his business.

“My policy is ‘Enjoy, don’t destroy, and animals first,’” he said. “If I see people chasing whales, I’ll yell at them, and if they are my customers, I’ll kick them off the water; they’re done.”

Getting too close to whales can also be dangerous for people. This was demonstrated dramatically by a freak accident in 2002 in which a recreational fisherman out of Morro Bay was killed when a large whale unexpectedly breached over his boat, smashing onto the boat and hurling the man into the water.

Several other fishermen were on the boat at the time of the accident but were unhurt. They were unable to identify the species of the whale, but a humpback or gray whale is considered the most likely.

New normal?

While humpbacks feeding close to shore are a relatively rare event, Forney said there is evidence it is getting more common, possibly caused by warming ocean temperatures and climate change. Forney lives in Moss Landing and has seen whales in Monterey Bay every day for a year and a half.

“The ocean out there is always changing, and it seems like we may have entered a new paradigm,” she said. “The last couple of years have had more whales close to shore than anyone can remember.”

This story was originally published September 4, 2015 at 11:00 PM with the headline "Humpbacks call coast home … for now."