Landbird monitoring 2017 annual report, Channel Islands National Park

Hall, Linnea; Larramendy, Peter; Power, Paula

The National Park Service (NPS) began monitoring landbirds at Channel Islands National Park in 1993 as part of its long-term ecological monitoring program for the park, which also became part of the NPS Inventory and Monitoring Program’s Mediterranean Coast Network. In 2017, landbird monitoring at Channel Islands National Park was conducted in collaboration with the Western Foundation of Vertebrate Zoology. Data were collected using distance-based sampling methods on established line transects and point count sites per protocol review recommendations proposed in 2000. The objectives of the landbird monitoring program are to 1) determine long-term trends in species composition, distribution, and abundance of native and non-native landbird species in selected areas of Channel Islands National Park, and 2) improve our understanding of breeding bird – habitat relationships and the effects of management actions, such as alien plant and animal control on bird populations by correlating changes in landbird species composition, distribution, and abundance with changes in specific habitat variables. This report provides simple summaries of raw observational data collected using distance-based sampling methods for landbird monitoring in 2017 between 1 March and 27 May at line transect and point counts. Fifty-seven landbirds species were counted across all islands in 2017. Parkwide, the 10 most commonly detected landbirds in 2017 were, in descending order, Spotted Towhee, Song Sparrow, Western Meadowlark, Orange-crowned Warbler, Bewick’s Wren, Horned Lark, House Finch, Common Raven, Island Scrub-Jay, and White-crowned Sparrow. Non-native and invasive birds were counted on only two of the five islands: Brown-headed Cowbird and European Starling on Santa Rosa, and European Starling on Santa Cruz. Results tables show 1) individual counts by species for each island, 2) frequency of detection for each species across sites on each island, 3) new transient or visiting bird species counted in 2017 and all other years since monitoring began, and 4) patterns of species detections identified those not counted in the last 10 or more years.

Landbird monitoring 2017 annual report, Channel Islands National Park

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