(AP) -- The U.S. Coast Guard on Wednesday monitored the waters off Santa Cruz, where a pod of whales has settled unusually close to shore drawing crowds and threatening the safety of kayakers and other boaters trying to get a look at the creatures.
The humpback whales, each measuring about the length of a school bus, have come about a mile from land in search of food.
The Monterey Bay National Marine Sanctuary said no one has been hurt so far but at least one sailboat was damaged this week when it struck a whale.
"The sheer number of folks crowding around the whales is not only an issue for the whales themselves, but also public safety," Paul Michel, the sanctuary's superintendent, told The San Francisco Chronicle. He estimated that 100 people took to the ocean on paddleboards and in kayaks last weekend to get a look.
He worried that the gawkers might disrupt the whales as they eat and leave them without enough energy to make their migratory journey to Mexico.
On Tuesday, the sanctuary and Coast Guard issued warnings for people to stay at least 100 yards away from the whales or face fines of at least $2,500 for whale harassment.
Don Croll, a professor in ecology and evolutionary biology at UC Santa Cruz, said whales are good at avoiding people while feeding but getting too close could pose safety risks. He said the whales are "lunge feeding," which involves dropping their jaw and swimming just below the surface capturing everything in their path.
Croll said watching such a spectacle - from a safe distance - is a thrill.
"Lunge feeding is probably one of the largest biomechanical events on the planet. It's a really, really great thing for people to see," he said.
Feeding grounds for the humpbacks are usually farther offshore, but scientists said this year weather conditions have brought anchovies closer to land, and the whales have followed.
The whales are likely to stick around Santa Cruz for another few weeks before continuing south.
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