Measuring the health of Mt. Tam

Maintaining a healthy, vibrant and diverse Mt. Tam begins with understanding how key ecological resources are faring, and how we can better care for this iconic and beloved place.

One Tam partners and Bay Area scientists have come together to try to answer the question: How healthy are Mt. Tam's natural resources?

Grassland Birds

Grassland Birds

Photo by Ken Schneider


The overall condition of grassland-associated birds is Unknown.

Point Blue Conservation Science was unable to assess patterns of abundance from 1996 to 2013 because data were insufficient for grassland-associated birds (see References below). This is likely because the data are primarily from Marin Municipal Water District lands of which grassland acreage is low and because grassland birds naturally occur in relatively low densities.

The need for a standardized monitoring program that covers all One Tam agency lands was identified as a critical data gap through this health assessment process. Because grassland birds are declining both regionally and statewide, additional surveys should be implemented to determine the condition of grassland birds in the One Tam region.

Condition, Trend, and Confidence for Grassland Bird Species Included in This Analysis


State of the Birds San Francisco Bay 2011 Point Blue Conservation ScienceMarin Audubon Christmas Bird Count California Bird Species of Special Concern
Abundance Patterns of Landbirds in the Marin Municipal Water District: 1996 to 2013

Learn More


Cormier, R.L., Seavy, N.E. & Humple. D.L. (2014). Abundance patterns of landbirds in the Marin Municipal Water District: 1996 to 2013. Point Blue Report. Available here

Pitkin, M. & Wood, J. (Eds). (2011). The State of the Birds, San Francisco Bay. PRBO Conservation Science and the San Francisco Bay Joint Venture. Available from:

Shuford, W. D., & Gardali, T. (eds.). (2008). California Bird Species of Special Concern: A ranked assessment of species, subspecies, and distinct populations of birds of immediate conservation concern in California. Studies of Western Birds 1. Camarillo, CA: Western Field Ornithologists, and, Sacramento: California Department of Fish and Game. Available from