Streaked Horned Lark Habitat Management and Monitoring at the Willamette Valley National Wildlife Refuge Complex -2018 Annual Report

The Willamette Valley NWR Complex provided several hundred acres of potentially suitable habitat for breeding streaked horned larks (SHLA) during 2018. Habitat was provided at all 3 of the Complex refuges: Ankeny NWR, Baskett Slough NWR, and W.L. Finley NWR. Management included both active (specifically for SHLAs) and passive (as part of goose forage production) actions. Monitoring results suggested that a seasonal maximum of 52 SHLA breeding pairs used the Complex’s agricultural fields during the 2018 breeding season. We observed up to 104 independent SHLA fledglings (substantially more than during previous years); a small number were observed in mid-June, but most were seen in July and August. Substantial habitat acreages seemed available during the early SHLA breeding season, but fields quickly became too vegetated to support SHLAs. Planned reproductive monitoring efforts were precluded by postponed hiring authority/budgets. Disking, chemical fallowing, and a prescribed fire prolonged habitat availability into summer. Wet swale (vernal pool) habitats seemed to provide the best SHLA breeding habitats, which generally remained available to breeding SHLAs throughout the breeding season. The Complex will continue managing for SHLA breeding habitats during 2019, and will pursue modifications to actively managed fields that could prolong habitat availability into late summer, when reproductive success seems to be greater. We also plan to continue our monthly breeding pair surveys, and to institute intensive reproductive monitoring (nest and fledgling success).