BERKELEY (KPIX 5) — No one has seen any endangered burrowing owls at  Berkeley’s Cesar Chavez Park since 2017, when one was found dead, and many feared the birds were gone for good. Now that they’ve returned, people are talking about what to do to keep them there.

People come to the park from all over the East Bay to let their dogs run free on the vast, 17-acre “no leash” field. But right next to that a protected area is the nesting spot of the burrowing owls, who take up residence in former ground squirrel burrows.

The birds are tiny—8 to 10 inches tall—and even people who go there everyday may not have noticed them.

“I didn’t know they were little teeny tiny owls,” said professional dog walker Frances Gandy. “I thought they were big owls that lived underground!”

But Marty Nicolaus knows the owls well. He photographs and records them almost daily for his website He was worried when none of them arrived last winter.

But this October, eight to ten of them showed up and two stayed. Now that they’re here, he’s concerned that a small minority of dog owners could ruin it for everyone.

“They don’t really think of the park as a place where there’s nature and wildlife has any rights,” Marty said. “They just see it as a dog run.”

He captured video of an owl perched on a rock and a few seconds later, an unleashed dog wanders into the protected zone and flushes the bird out making it fly away. Marty said more needs to be done so the dogs will not drive the owls away for good.

“A good dog culture requires an ample space, doesn’t have to be 17 acres, and a fence around it, so that there’s some boundary as to where the dog can go,” he said.

But the large unfenced romping place is exactly why dog walkers—many of whom do it for a living—love it and consider it a unique resource in the Bay Area. They say the vast majority of dog owners respect the leash rules, but they also realize what could happen because of the few who don’t.

“If we start seeing more individuals going into the environmentally-safe areas, then we will lose the ability to access this park,” said Oakland resident and dog owner Ben Mow. “And that would be…that would be terrible.”

An Audubon Society survey from last year showed 75 percent of owners had their dogs leashed near the owl refuge area. That’s up from 68 percent the year before, but it still means that 1 in 4 dogs in the area were unrestrained.