ONE TAM COLLABORATION LOCATES RARE BEE SPECIES

The Golden Gate National Parks Conservancy, working with the National Park Service, California State Parks, Marin Water, and Marin County Parks as the One Tam partnership, announced the discovery of the rare San Francisco leaf-cutter bee (Trachusa gummifera) in Marin County. Scientists have documented the bee, which is endemic to the Bay Area, less than 100 times total, and not since 1980. Tamalpais Bee Lab, a community science program of One Tam, found the bee on public lands in Marin County. The discovery came out of One Tam’s work to monitor the health of the Mount Tamalpais region. “It’s a big win and highlights the benefits of our One Tam collaboration,” said Mischon Martin, chief of Natural Resources and Science for Marin County Parks. “One Tam has always been about leveraging resources on the ground — providing opportunities for community science, conducting biological surveys, and coordinating the work of local, state, and national land managers — we wouldn’t have found this species without working together like this.” In initial surveys from 2017-2022 to inventory the local bee community, the San Francisco leaf-cutter bee was not detected. In the following years, One Tam devised a new community science effort, a search party, to locate it. With confirmation from the U.S. Department of Agriculture, the Tamalpais Bee Lab team documented sightings of the species while scouting potential survey sites this summer. The San Francisco leaf-cutter bee is a species of greatest conservation need in California’s State Wildlife Action Plan and one of the California Department of Fish and Wildlife’s terrestrial invertebrates of conservation priority. “How exciting it is to find a bee that hasn’t been seen in so long,” said Hillary Sardiñas, pollinator coordinator at California Department of Fish and Wildlife. “If a species turns up after 50 years, it gives us hope that others are still out there, too. We need local efforts like One Tam’s search parties to support our most imperiled insect species.” Now that the bee has been found, One Tam is working with fish and wildlife officials to obtain the permits necessary to continue investigating this special status species. “This is hopeful news in a time when we are hearing a lot about trouble for insects, especially pollinators,” said Sara Leon Guerrero, community science program manager at the Parks Conservancy, who manages the Tamalpais Bee Lab and made the initial sighting. “We’re excited for what’s next — the chance to learn more about this species that’s largely unknown to us, and to invite the community to learn along with us.” Learn more about the Tamalpais Bee Lab here: onetam.org/tamalpais-bee-lab.