Habitat Characterization of Breeding Territories of the Western Yellow-Breasted Chat in the South Okanagan, British Columbia, Canada

Abstract

From 2002 to 2007 we measured breeding territory, nest patch, and nest shrub characteristics for Yellow-breasted Chats (Icteria virens auricollis) in the northern edge of their distribution in British Columbia, Canada. Surveys were done at 94 breeding territories, 238 nest patches, 246 nest shrubs, and at random locations for comparison. Habitat selection by chats was not random, and territories were selected for specific vegetation characteristics. Chat breeding territories were located in lower elevation riparian zones consisting mainly of dense shrubs and early successional water-tolerant trees, with the dominant shrub species being wild rose (Rosa spp.). Chats nested in 12 plant species and 72% of nests were within wild rose, which was also the dominant species in 5 m and 11.3 m radius nest patch plots centered at the nest shrub. Based on georeferenced locations of male chat singing or perching locations, chat breeding territories were on average 0.37 ha (s = 0.27 ha) in size (n = 66).