May 27, 2020

Congratulations to Van Hoosear Wildflower Preserve in the Sonoma Mountain area and Cooley Ranch in northern Sonoma County for hosting Northern California burners who put good fire on the ground this past Memorial Day weekend. Both of these controlled burns on privately held lands went off without a hitch, another sign of the growth of prescribed burn partnerships in the region.

May 09, 2020

While we work from home, the miles logged by shorebirds we have radio-tagged has us longing for an unconfined drive to points beyond—a birding trip to the Central Valley, a camping trip along the North Coast, or more miles logged on the Pacific Crest Trail.

Alas, we take solace in science and focus our gaze on two determined Long-billed Curlews fitted with radio tags in February at Limantour Beach under a partnership with the Smithsonian Migratory Bird Center, the Coastal Bend Bays and Estuaries Program (Texas), and Boise State University’s Intermountain Bird...

May 08, 2020


On Valentine’s Day this year, Luna (P16) gave birth to her first litter of kittens. She is only 3 years old and so a young mother. As we watched her awkward attempts to care for these new, tiny, and foreign creatures, we wondered what their chance of success would be. At first, we thought the den site chosen was far too exposed, and waited to find them killed by a passing predator while mom was away hunting. To our surprise, they survived...

April 11, 2020

Hello Friends,

I hope you are well and that nature, unencumbered by the frenetic pace of modern life, has shown you her beauty in new ways. As one of two resident staff members at ACR’s Cypress Grove Research Center on Tomales Bay, I can report that the natural world is moving around just fine—wintering waterbirds are heading to their northern breeding areas, while the Great Egrets we are tracking are sporting some beautiful breeding plumes. Various songbirds are busy nesting, and coyotes, bobcat, and fox are on regular rotation.

A special highlight for me this spring has been the discovery of 5–10 individual California red-legged frogs (Rana draytonii) in one of the Cypress Grove ponds. This species is federally listed as threatened under the Endangered Species Act. My...

April 01, 2020


P19, a 22-month-old male mountain lion followed by Living with Lions in Sonoma County, has left home and the safety of mom to find his own way. Watch as over a few weeks beginning on March 9, 2020, this big cat sets a determined course east into the Central Valley and comes within 25 miles of Sacramento before turning back toward the safety of the Vaca Mountains. Remarkably, in his early travels he has crossed Interstate 80 twice and navigated the major intersections of Vacaville.

As a young dispersing male, this elusive top...

April 01, 2020

UPDATE: 5/18/20:

CLOSURE NOTICE: All ACR preserves in Marin and Sonoma counties remain closed until further notice due to the public health risks of Covid-19. Resident preserve managers and stewardship staff continue to protect and steward these incredible resources for both natural and human communities. We hope to see you on the trail in the near future. While you are exploring nature nearer to home, please visit our Nature Where You Are resource page for engaging nature content, lessons for all ages designed by ACR educators and links to some of our favorite science-based nature resources.

UPDATE: 5/8/20:

The beginning of May...

March 26, 2020

Each year for the past thirty years, our Heron and Egret Project (HEP) volunteers have sent us paper forms containing somewhere between six and seven thousand records of nest observations. It takes ACR scientists a good chunk of time at the end of each season to enter those in our database, along with their associated visit data (proofing everything twice!).


March 25, 2020

On February 22, 2020, Living with Lions program director Dr. Quinton Martins tracked down the first litter of kittens born to mountain lion P16 near Kenwood, Sonoma County on Valentine's Day. P16, named Luna by the landowners where she was captured, is a 2.5–3-yr-old female that was collared for the GPS tracking study in March 2019.

The team set up trail cameras to capture the interactions of Mama Luna and her kittens over the...

March 24, 2020

Coronavirus is upon us, and folks are flocking to the outdoors to fight that cooped up feeling of social isolation, with “outdoor activities” being included as an essential activity in many jurisdictions.  On one hand, this is good since being outdoors benefits people.  On the other hand, more travel to hiking and birding trails, especially in our small, rural communities like West Marin where we live and work, risks doing exactly what the experts do not want, increasing virus transmission. In fact, many local public health officials are asking people not to drive to beaches, open space, or parks outside their neighborhoods. As of 3/23/20, many open spaces here that originally remained open for public enjoyment have since been closed because of safety concerns due to...

March 11, 2020

The Long-billed Curlew is listed as a Bird Species of High Concern by the U.S. Fish and Wildlife Service as well as a Species of Special Concern in Canada. Some populations have declined dramatically in recent decades, with threats from loss of breeding habitat, especially grassland habitat, urbanization of agricultural habitat, and hunting.

Over the last 15 years, many collaborators, including ACR’s Nils Warnock, have been using lightweight satellite transmitters to track curlews from a variety of breeding and wintering areas and have achieved impressive coverage that spans most breeding states and provinces and most of the wintering range.

However, a large knowledge gap remains along the coast of California where many curlews winter but few of previously tracked birds...