July 09, 2021

Annual migrations of shorebirds are among the longest treks in the world. Whimbrels are among the most far-reaching, with movements between subarctic and Arctic breeding grounds to non-breeding locations in the southern hemisphere spanning up to 5,400 miles.

Not a simple point A to point B calculation, these annual trips vary in timing, site selection and more. Understanding variation in these traits among populations can help uncover mechanisms driving migratory behaviors and identify potential population threats.

In a study published this month in the Journal of Field Ornithology, ACR Director of Conservation Science Nils Warnock and co-authors set out to discover the nuances in movements of Whimbrels breeding in Alaska, a population that numbers nearly 40,000...

May 10, 2021

Juniper Junior Naturalist graduate to study sustainable farming at Cornell

Hunter Halkovich, pictured above with dog Moxy, is this year’s David Bouverie Scholarship recipient. Hunter has been an active Juniper Junior Naturalist since fifth grade and participated in many newt counts, helped build owl and bat boxes, and mentored younger Junipers. During the pandemic, he presented his work on silk (Polyphemus) moths at a virtual insect extravaganza.

Hunter was selected by the scholarship committee...

May 10, 2021

Emerging from the past year of pandemic uncertainty, Audubon Canyon Ranch’s Living with Lions has more reasons to celebrate our community’s quest to understand Sonoma County’s mountain lion population and further ecosystem conservation throughout the region.

In the past two months since being able to resume lion captures, Dr. Quinton Martins, who has directed the research for the program, has collared or tagged five big cats throughout the county, recorded a new litter...

April 23, 2021

A photographic love letter

In gratitude for all the ways you support nature and our work to preserve and steward these lands, we've gathered our best wildflower and wildlife photos taken this season—a video love letter from our preserves. Enjoy! BONUS! Watch to the end for new footage of one-month-old mountain lion kittens.

April 20, 2021

Tracking the movements of mountain lions using GPS collars is integral to understanding the population and ecology of such an elusive yet charismatic cat living amongst us here in the Valley of the Moon. The Living with Lions project had an exciting beginning to 2021, capturing and collaring five lions that will allow us to further monitor the fascinating behavior of Sonoma County’s lions, while also helping to reduce deadly run-ins between lions and local pets and livestock.

I often receive phone calls after residents’ sheep and goats are killed, which recently led to the capture of large male mountain lions P24 and P25 in the Healdsburg and Cazadero area, as well as an interesting female in the Bennett Valley/ Penngrove...

March 25, 2021

While the pandemic has raged, thanks to generous grants from the Marin Wildlife Commission and an ACR donor, ACR science staff have been busy this winter acquiring the equipment needed to set up two remote telemetry receiving stations (known as Motus stations) on Tomales Bay to aid in our efforts to better understand the movement ecology of our local bird populations as well as other wildlife.

Tracking wildlife: weighing the options

Historically, biologists use a couple of proven technologies to track the movements of birds and other wildlife: radio telemetry/VHF or satellite/GPS tags.

Very high frequency (VHF) tags emit a low power signal at a specific frequency that the biologist listens for using a portable receiver and an antenna. These tags...

March 06, 2021

Tracking the movements of mountain lions using GPS collars is just one part of ACR’s Living with Lions project but it is essential to understanding the lion population as a whole. When a collaring opportunity arises, we have a short window for success. Recently we received three calls in rapid succession from residents who suspected mountain lions were responsible for deer and livestock kills on their property.

On February 22 Quinton Martins received a call about a dead deer found partially buried in leaf matter (called ‘caching’) in the front garden of a Sonoma Valley property. Upon investigation it was clear a mountain lion had made the kill, so with the landowner’s permission, Quinton set a trap to capture and collar this animal.

That night, the lion returned to...

March 06, 2021

ACR researchers recently published a paper in Condor, Ornithological Applications, reporting trends of Tomales Bay shorebird populations. Overall, most species of shorebirds have declined substantially on Tomales Bay in the last 30 years.

Tomales Bay: An important wetland for wintering shorebirds
Each year tens of thousands of shorebirds breed in the high latitudes during the summer then migrate to warmer latitudes for the winter. Tomales Bay, located within the Point Reyes National Seashore north of San Francisco Bay, has been recognized as an important wetland for these wintering shorebirds.

Across North America bird species—including shorebirds—are declining but it is often unclear how local factors across species’...

February 05, 2021

ACR Executive Director John Petersen will retire at the end of March after a 35-year career in conservation. A Board-directed executive search is underway; Nils Warnock, Ph.D., currently director of conservation science, has been appointed as the interim executive director, beginning on April 1.

“Under John’s leadership, ACR is tackling the region’s ongoing conservation challenges of dwindling biodiversity and climate-driven wildfire in ways that have delivered better outcomes for ourselves, our wild neighbors and the complex ecosystems of Northern California. His persistence in these areas will improve quality of life for generations of North Bay residents,” said Phillip Carlsen, president of ACR’s Board of Directors, in a note to supporters.

In the nearly four decades...

February 02, 2021

Explosion of woolly mullein

On the Modini Preserve in the northern Mayacamas Mountains, new post-fire populations of the non-native, woolly mullein (Verbascum thapsus) have exploded in several areas of burned knobcone pine (Pinus attenuata) understory—areas that were dominated by native species last spring.

Native to Eurasia, woolly mullein was intentionally introduced to the U.S. many times due to the plant's medicinal qualities. It relies on periodic disturbance for seedling establishment, which is greatly enhanced when there is bare ground—taking full advantage of conditions in play on the Preserve after the 2019 Kincade fire.

In our region, you may notice woolly mullein's typical biennial growth—in the first year, the seedlings will mature into large, dusty-...

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