Every year, between February and July, black-crowned night herons and snowy egrets take over a three-block radius of downtown Oakland. From Alice and 14th Street, to Jackson and 12th, chicks that have fallen from their nests and bird droppings stain the pavement.

These species are the most common bird nesting downtown. They are social nesters, meaning they nest together in large groups. The mighty flock has spent each season here for the past decade.

Marissa Ortega-Welch, an education manager at the Golden Gate Audubon Society, said her organization began to pay closer attention to the annual gathering after reports surfaced of local business owners cutting down nesting trees, which is against federal law.

The Audubon Society sends volunteers to the area each week to count nests, rescue fallen chicks, and better inform the public about the heron and egret habitat. “We realized we’re Audubon, we do bird advocacy. We have to get involved, and maybe help balance the love/hate, and provide information so people understand that the birds are protected,” said Welch.

In order to work more efficiently, the Golden Gate Audubon Society has partnered with the Oakland Zoo to rescue baby birds and collect more data about the colony. Over the past few weeks, teams have saved over a dozen chicks. The Oakland Zoo “rehabilitates the bird, then releases it back into the wild, instead of it dying out here on our streets,” added Welch.

Even if a chick survives falling on the pavement, they are still in danger of dying from starvation or being hit by cars. Most of the chicks that do get stuck on the ground are too young to fly back into the tree. Parent egrets and herons will only feed baby birds that are in the nest, because it is too risky for them to be on the sidewalk.

“The birds we try to rescue have full flight feathers. They’re able to walk, and can fly very short distances, but it’s more like hopping. They can’t fly far enough to go back into the tree and be fed,” said Welch. “So they are almost like they are the equivalent of a teenager–like, old enough to strike out on their own, but not old enough to always succeed.”

Before parking lots and condominiums were built around the heron and egret habitat, Lake Merritt’s original boundaries once sprawled three blocks further onto Alice and Jackson Streets. When it was just an estuary and arm of the bay, the colony’s chicks had short trees and vegetation to catch their fall. “So this is their natural habitat, and we really came in and put this city underneath them, put this parking lot underneath them,” said Welch.

Welch will be holding a public walking tour on May, 19 at 6 pm. Participants are expected to meet in front of the Oakland Public Library’s downtown main branch. She hopes to not only rescue more herons and egrets, but also better inform the public about their nesting habitat.

Click on the video above to watch Welch on a heron rescue mission in downtown Oakland.