Sierra Nevada Management Indicator Species

This website, hosted by the California Avian Data Center (CADC) at PRBO Conservation Science, will allow users to quickly and easily generate location and summary data from tens of thousands of species occurrence records over many hundreds of point counts across the Sierra Nevada region.

The Sierra Nevada Management Indicator Species (SNMIS) project aims to conduct distribution population monitoring of four management indicator species (MIS) in order to track changes in their distributions at the Sierra Nevada scale by monitoring the changes in their occurrence across a number of sample locations. The study plan can be downloaded here.

In 2007, the Sierra Nevada Forest Plan was amended to adopt a common list of MIS and associated monitoring strategies for all ten forests in the Sierra Nevada: the Eldorado, Inyo, Lassen, Modoc, Plumas, Sequoia, Sierra, Stanislaus, and Tahoe National Forests and Lake Tahoe Basin Management Unit. The amended MIS strategy identifies eleven terrestrial habitats or ecosystem components and twelve wildlife species whose populations are designated to be indicative of habitat management.

We have designed a plan for monitoring and evaluating the response of four of the twelve species selected by the Forest Service to help guide management of the 10 Sierra Nevada National Forests. Mountain Quail (Oreortyx pictus) was selected as the indicator for early and mid-seral conifer forest, Fox Sparrow (Passerella iliaca) as the indicator for chaparral shrubland, Yellow Warbler (Dendroica petechia) as the indicator for riparian habitat, and Hairy Woodpecker (Picoides villosus) as the indicator for snags in green forest.

In order to sample the distribution of these four species across the National Forests of the Sierra Nevada, we are using standardized point count method (Ralph et al. 1995, Ballard et al. 2003) where a single observer estimates the distance to the location of each individual bird they detect within a five minute time span from a fixed location. Call-playback surveys are also conducted (for Hairy Woodpecker and Mountain Quail) on a subset of the point count locations by broadcasting the vocalizations of these species and then listening for a response.

We have implemented a generalized random-tessellation stratified (GRTS) sampling scheme to distribute survey locations evenly across the region to avoid clustering in any given area (one particular forest for example) while remaining random at the local level to avoid bias due to natural spatial patterns of habitat and physiognomic conditions. We located survey sites in upland montane chaparral and "green forest", as well as in riparian areas (to target Yellow Warbler habitats). Currently we are only showing results from the upland locations. We selected a broad set of habitats so that any CWHR types that are currently considered appropriate habitat, or could transition to them through natural processes or management actions (e.g. fire, silvicultural treatments) are included. Thus we chose to include all conifer forest regardless of age structure, since even old-growth stands have the potential to become early-seral forest. Furthermore, we limited the set of potential survey locations to areas within 1 kilometer of roads, elevations between 1000 and 2800 meters, and on slopes less than 40%.

Point count survey locations are arranged in a diamond-shaped transect of four point count stations (black dots) surrounding one call-playback station (gray dot) at the center (see figure below), and two transects are located 1km apart in either a north-south, or east-west arrangement. The four point count locations are 250m from the call playback station in the four cardinal directions (each point count location is 354m apart).

The results of our first field season are available on this website. Metrics that are available to generate include: locations, density, species richness, diversity, and (in the future) occupancy and potentially many other data. These data can be used to examine the locations of surveys, the species recorded, the distribution of particular species, and summaries of various metrics within any area of interest down to the Forest District level. You can also download raw data and conduct analyses for yourself. Because we currently have only one year (2009) of results available, there are no trend data available.

To get started, please select one of the options at the top of the screen and follow the step-by-step instructions.