Bay Nature magazineFall 2022


How Healthy Is the East Bay’s Habitat?

NatureCheck's collaborators are looking at key species to find out.

November 2, 2022
Sponsored by East Bay Stewardship Network

From the eastern shore of San Francisco and San Pablo Bays stretch Alameda and Contra Costa Counties, home to more than 2.8 million people and hundreds of wildlife species. The East Bay is a place where mountain lions travel just out of sight, burrowing owls may overwinter on the edge of airport runways, and red-tailed hawks soar over highway traffic. Here boundaries between human and nonhuman communities blur. The checkerboard of dense urban areas, roaring freeways, and residential neighborhoods is interwoven with channeled streams, farms and ranches, redwood forests, oak woodlands, grasslands, and wetlands.

Logo for NatureCheck, a habitat assessment in the East Bay

NatureCheck is a scientific collaboration looking at indicator species to assess East Bay habitat. You can read the full report here. (Illustration by Jane Kim)


Measuring Migration From the Hills to the Sea Rainbow trout depend on healthy streams.

The Wildlife-Rich Grasslands Checking in on ground squirrels, tiger salamanders and golden eagles.

What Bats Tell Us Meet the Bat Brigade, looking out for the East Bay’s 16 bat species.

“Our wildlife is under a lot of pressure,” says Doug Bell, wildlife program manager for the East Bay Regional Park District (EBRPD). “But having said that, it’s a miracle we still have the wildlife we have. This area is so diverse.”

But how well is this landscape supporting our wildlife neighbors? Becky Tuden, ecological services manager at EBRPD, wanted to know. “If you think of the ecosystem like the human body, we have a whole series of metrics for measuring the health of the system, like blood pressure, blood oxygen level, pulse,” Tuden says. “How can we assess the health of a landscape?”

In other words, what is the East Bay’s ecological pulse?

The question launched the East Bay Stewardship Network—a coalition of five agencies that together manage more than 225,000 acres of public land, almost a quarter of the land area in the East Bay, for uses ranging from recreation and drinking water reservoirs to power lines and energy production. For wildlife, though, these lands are home. They “are interconnected,” says Josh Phillips, ecological services coordinator for EBRPD. “Wildlife don’t recognize the lines on our maps.”

Map: Molly Roy; Map illustrations: Jane Kim.

The network drew inspiration and guidance from One Tam, a similar consortium of land agencies assessing the health of Mount Tamalpais in Marin. After four years of work that brought agency scientists together in a groundbreaking collaboration, the network published its inaugural findings in a report, NatureCheck: Understanding Wildlife Health on East Bay Lands in Alameda and Contra Costa Counties, in April. Agency scientists divided the East Bay into three subregions—the East Bay Hills, Mount Diablo Range, and Mount Hamilton Range—and organized their assessment by indicator species. A species, or group of species, acts as a barometer for the health of its particular area. By compiling species data from 2009 through 2020 across jurisdictional boundaries, agency scientists have created for the first time an ecological snapshot of the region, a baseline from which they can continue to monitor and assess the health of East Bay wildlife. 

The good news so far: Nature indeed has a strong pulse in the East Bay. But that’s not something we can take for granted. NatureCheck does not incorporate the last two years of drought, and there are some considerable data gaps to fill for versions of the report to come. Future iterations of NatureCheck will include updated data sets, along with data on vegetation and invertebrates, and will be published roughly every five years.

“We’re taking very basic measurements to get these indicators of health,” says Tuden, “but that’s more than we’ve ever had on this scale.”

How you can help

NatureCheck is the result of a treasure trove of existing data that includes amphibian surveys at hundreds of ponds through the East Bay, annual electrofishing and snorkel surveys, ground squirrel max count and transect surveys, bat exit surveys, camera trap data, monitoring surveys, and more. 

But the work of compiling this data is ongoing, which is how the public can get involved. Find more information about joining the Bat Brigade or other wildlife volunteer programs through the East Bay Regional Park District. NatureCheck also draws on data from the community science apps iNaturalist and eBird, two publicly available data sets based on wildlife observations made by the public. As you head into East Bay Stewardship Network lands, remember to log your photos or audio recordings on either platform. Your observations could contribute to a more accurate health assessment of our nature neighbors on publicly accessible lands.

To help care for local wildlife:
Stay on trails.
Pack out trash.
Follow leash laws.
Do not forage.
Obtain permits to fish.
Keep cats indoors.
Reduce artificial light use at night.

East Bay Stewardship Network Partners
About the Author

Austin Price is a Berkeley-based writer who reports on conservation, food, and natural
history. His recent work has appeared in Sierra, Edible East Bay, Yale Environment 360, and Earth Island Journal, where he’s a contributing editor. While he was reporting on bats, his gratitude grew for all they do for us, from eating mosquitoes to pollinating Agave tequilana. He’d now call himself a bat advocate, with or without a tequila drink in hand.