The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2022

Type
Report
Year of Publication
2022
Authors
David J. Lauten
Kathleen A. Castelein
Daniel Farrar
Mary Lee
Eleanor P. Gaines
Date Published
Dec. 1, 2022
Abstract

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the central and south coast of Oregon from 1 April – 15 September 2022. We surveyed and monitored plover activity in a project area that included, from north to south, Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River Habitat Restoration Area (HRA) and adjacent lands, and Floras Lake. Our objectives for the project area in 2022 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes and signs), 5) monitor a sample of broods to determine brood fate and plover productivity, and 6) use cameras and observational data to document predator activity at nests.

We estimated the resident number of Snowy Plovers in Oregon at 508 individuals, the first decline since 2016. We monitored 529 nests in 2022. Overall apparent nest success was 24%. Nest failures were attributed to unknown depredation, unknown cause, corvid depredation, unknown avian depredation, harrier depredation, abandonment, mammalian depredation, one egg nest, wind/weather, overwashing, gull depredation, and infertility. We sampled 90 of 125 known broods that produced 96 fledglings and estimated 130 total fledglings. Overall brood success was 72%, fledging success was 44%, and based on the overall number of resident males, 0.49 chicks fledged per resident male.