Jump to: Pinyon Jay – Yosemite toad – Marbled Murrelet – Wolf recolonization
Pinyon Jay

The Pinyon Jay has declined by nearly 50% over the last 30 years. Yet its complex use of diverse habitats across the interior west – and prioritization of sagebrush obligate species – has challenged conservation efforts. The U.S. Fish and Wildlife Service is now considering the jay for listing under the Endangered Species Act, so we are collaborating with the Great Basin Bird Observatory to develop scalable survey protocols that the USFWS, U.S. Forest Service, Bureau of Land Management, and other agencies can use to assess populations across the landscape. The jay is highly social species that can form flocks numbering into the hundreds, so we will also be exploring acoustically-based abundance estimation and linkages between pine cone crops and flock size.
We also participate in the Pinyon Jay Working Group, a collaborative effort to coordinate and support conservation research focused on the jay.
Yosemite toad

Like many amphibians, the Yosemite toad is declining. Yet the causes have been difficult to diagnose because annual surveys of the adult population are very difficult to conduct. The Yosemite toad breeds immediately after snowmelt in high-elevation meadows in California’s central Sierra Nevada, which means accessing sites when adult toads are most conspicuous is very difficult.
- In spring 2021, I conducted a pilot study which showed that we can deploy autonomous recording units before the snow melts, retrieve them later in the summer, and then use BirdNET to identify the vocalizations of Yosemite toads, as well as Pacific chorus frogs. I made a short video about that field effort, which helped me obtain a Discovery Expedition Grant from The Explorers Club.
- In spring 2022, supported by the DEG, I conducted a six-day expedition into the High Sierra to deploy 14 recording units across an area that is only rarely surveyed for the toad. That work was featured briefly on Discovery’s new show “Tales from the Explorers Club”. I also wrote about the project for ‘The Snowboarder’s Journal’.
- In spring 2025, supported by Patagonia, I conducted another six-day expedition into the High Sierra with professional splitboarders Nick Russell and Forrest Shearer. A multimedia story about that trip will be released in spring 2026….
The ongoing US Forest Service toad monitoring project conducts mark-recapture surveys at a few breeding areas, and the next step is comparing vocalization counts to adult population counts to derive an acoustic-based population index that could be applied more broadly.
Publications
- Wood, CM, S Kahl, R Van Horne, and C Brown. Passive acoustic surveys and a novel machine learning tool reveal detailed spatiotemporal variation in the vocal activity of two Anurans. Bioacoustics. doi: 10.1080/09524622.2023.2211544.
- Wood, CM, J Champion, C Brown, W Brommelsiek, I Laredo, R Rogers, and P Chaopricha. Challenges and opportunities for bioacoustics in the study of rare species in remote environments. Conservation Science and Practice e12941.
Marble Murrelet

Federally Threatened since 1992 and state Endangered in California (1992), Washington (2016), and Oregon (2021), the Marbled Murrelet is an seabird that nests almost exclusively in old-growth forests along the north Pacific coast of North America. Current survey efforts are limited to time-intensive human surveys; passive acoustic surveys offer a scalable alternative to understanding where this species persists on the landscape. In collaboration with Brian Dotters of Sierra Pacific Industries and Dr. Zach Peery of UW-Madison, we are developing an acoustic survey protocol that can meet or exceed current regulatory standards for murrelet surveys in determining occupancy and nesting status in stands of old-growth forest. This project is led by graduate student Rylie Strasbaugh.
Wolf recolonization
In 1924, wolves were extirpated from California. In 2015, the first confirmed wolf returned to the state. As of 2022, according to the California Department of Fish & Wildlife, there were three wolf packs in the state. Information about wolf abundance and dispersal is a critical component to managing the potential conservation conflicts that can arise with the natural return of wolves. Their long-term future will depend in part on understanding pack size and distribution to facilitate co-existence with human communities. We are leveraging passive acoustic monitoring techniques to work with agency partners to support wolf management in California and beyond.
Looking beyond California, wolves are a global touchstone for conservation conflicts. By improving tools for wolf monitoring, we hope to mitigate the intensity of these conflicts and facilitate scalable conservation research for this iconic species.
Partners
UC-Davis, UC-Berkeley, California Department of Fish and Wildlife, U.S. Forest Service
Publications
- Sossover*, D, K Burrows*, S Kahl, and CM Wood. Using the BirdNET algorithm to identify wolves, coyotes, and potentially their interactions in a large audio dataset. Mammal Research. https://doi.org/10.1007/s13364-023-00725-y
