USDA Forest Service

Pacific Southwest Research Station

Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
United States Department of Agriculture Forest Service. USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.

Wildlife habitat occupancy models for project and landscape evaluations in the Lake Tahoe Basin

Principal Investigators:
Pat Manley, USDA Forest Service-Pacific Southwest Research Station
James Baldwin, USDA Forest Service-Pacific Southwest Research Station
Ross Gerrard, USDA Forest Service-Pacific Southwest Research Station

Proposal [pdf]

Final Report [pdf]

Please contact Dr. Pat Manley with questions regarding the final report.

Project Summary

A myriad of sources of environmental change and associated land management challenges exist in the Lake Tahoe Basin. Sources of change are diverse and include land development, recreational uses, wildfire, insects, disease, forest management, and climate change. The complexity of the challenge is four-parted:

  1. The broad suite and multifarious character of influences affecting forest ecosystem conditions.
  2. The limited information on historical conditions, particularly in regard to temporal and spatial heterogeneity.
  3. The prospect of rapid rates of climate change with uncharted ecological responses.
  4. The uncertainty of how best to achieve targeted conditions through land management.

The Lake Tahoe Basin needs an assessment tool that can be applied to a variety of wildlife and biodiversity evaluation needs to help inform land management planning and implementation in light of multiple interacting change agents acting across the landscape and over time. A rich array of empirical data is available and can be tapped to provide this important tool, and thereby increase the value of past and current agency investments in research and monitoring.

The goal of this project was to use existing empirical field data that were collected in a systematic manner in the Lake Tahoe Basin to develop species distribution maps and habitat occupancy models for forest-associated vertebrate species in the basin. These models will facilitate site and landscape-scale evaluations of management treatments, climate change, and other change agents that affect forest structure and composition today and in the future. This project developed habitat occupancy models (estimates of probability of occurrence have a range between 0 and 1) based on site-specific environmental conditions. These are first generation models, and as such, they target simple objectives that can be readily met with existing data.