Landbird Monitoring at Channel Islands National Park: 2022 Annual Report

Larramendy, Peter; Hall, Linnea; Little, Annie

doi:10.36967/2316511

The National Park Service has monitored landbirds at Channel Islands National Park (CHIS) during every breeding season since 1993 as part of the Mediterranean Coast Network Inventory and Monitoring Program. In this report, we summarize data collected during the breeding season (March through May) of 2022. We used distance-based sampling methods and a standardized protocol to count landbirds at 97% (331 of 338) of the CHIS permanent point count stations on East Anacapa Islet, Santa Barbara Island, Santa Cruz Island, San Miguel Island, and Santa Rosa Island. Counts were not made at seven point count stations on Santa Barbara Island due to the presence of nesting California Brown Pelicans, and at three of these stations, counts have not been made since 2015 to avoid disturbing nesting pelicans. Across point stations on all five islands, 56 species of landbirds were counted in 2022, 40 of which breed at CHIS. In descending order, the ten most detected landbirds at CHIS in 2022 were Spotted Towhee, Song Sparrow, Orange-crowned Warbler, Bewick’s Wren, Western Meadowlark, House Finch, Horned Lark, White-crowned Sparrow, Common Raven, and Pacific-slope Flycatcher. The fewest number of landbird species were counted on East Anacapa Islet (5), while the greatest number were counted on Santa Cruz Island (42). While non-native and invasive birds were counted on only one of the five islands in 2022 (17 European Starlings on Santa Rosa Island), anecdotal sightings of non-native species occurred more frequently on both Santa Cruz and Santa Rosa islands. For example, Santa Cruz Island had the highest number of anecdotal sightings of non-native species (19) in 2022: 12 European Starlings, four Eurasian Collared-Doves, and three Rock Pigeons. Density analyses were conducted for three species across Santa Cruz and Santa Rosa islands, and one species, Northern Flicker, had a significant decreasing density trend from 2016 to 2022. Management priorities related to landbirds in CHIS over the coming years include (1) implementing a removal strategy for European Starlings on Santa Rosa Island, (2) increasing the sample size of count stations on Santa Rosa Island to increase the encounter rate for Chipping Sparrows, and (3) implementing a second visit to East Anacapa Islet in future monitoring seasons to increase the encounter rate for Orange-crowned Warblers and improve our ability to estimate the density of this species.

Landbird Monitoring at Channel Islands National Park: 2022 Annual Report

Series

Other versions

See also