BERKELEY, Calif. (KGO) -- Abigail Chavez brings the toddler she baby sits to Tilden Little Farm every week.
"It's really useful to entertainment. Especially without (having) them inside, using their iPads and things like that," she says.
The little one loves to feed the cows. And, sometimes they take selfies for social.
"Yeah, we take pictures all the time!" say Chevaz.
At Little Farm, the animals are captive and used for human interaction. But out in the East Bay Regional Park District's open spaces, it's not always a good idea to try and snap a selfie.
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"Bad idea! Definitely, (because) most cows are pretty protective of their babies. And they weigh about 1,000 pounds, the hill cow. So that's a lot of muscle to have heading your way," says Stanley Ward, the farmer at Little Farm.
The park district uses animals like cattle to graze over almost 87,000 acres. August to October is calving season, when interactions with calves can be a danger to both people and animals.
"These calves are not the kind of cows you find on little farm. It's not a petting zoo. They are range cows. They are meant to be in these wild lands," explains Allison Rofe, a Range Land Specialist at the East Bay Regional Parks District.
She has some tips when out in the open spaces: Do not approach or touch calves. No selfies with calves. Do not get between a mother and her calf, keep dogs on a leash.
"(Cows) are not defensive by nature. They may present perceive dogs as a predator, especially around their calves," says Rofe.
The park district says if you encounter a calf and cow along a trial, give them time to move or go off trail to get around them.