Point Count Survey - Terrestrial Species Stressor Monitoring [ds2829]

Avian point count surveys were conducted at 184 Great Valley study sites, and 107 Mojave Desert sites, between March and June 2017. Whenever possible, three independent point count surveys of five minutes each were conducted over the course of the month-long survey period at each site. To enable relatively accurate distance measurements, observers would mentally mark 50 meters in each cardinal direction using a rangefinder. Observer qualifications determined the complexity of the survey being conducted, with a focal survey recording data for only 25 pre-designated species; for comprehensive surveys, data for all bird species was collected. During survey site establishment visits, a 15-minute quiet period was taken at the point count center prior to starting the survey; subsequent visits only required a 5-minute quiet period. During the quiet period, the observer recorded general information about the survey location, weather, etc. During the point count, observers recorded the name of each species using six letter codes. Individuals of each species were tallied within the three different distance categories: < 50 meters, > 50 meters, and flyover. Birds seen at multiple distances were recorded only at the closest distance. Observers also recorded the confidence level of their observations and the type of detection (aural and/or visual). When individuals were detected at different confidence levels, the observer created distinct entries of the species and separated them by confidence. If an unknown species was detected, the observation was labelled as UNK, numbered, recorded with the technician’s best guess to species ID, and marked at low confidence (e.g. UNK1 – HOUFIN).