AVIAN MONITORING
Westcave Preserve provides a unique patchwork of different habitats for resident and migrant bird species alike. Westcave is currently home to 163 bird species. Many of these species are neotropical or grassland birds which have declined dramatically over the past 40 years in North America.
GOLDEN-CHEEKED WARBLER SURVEY
One of the more celebrated bird species at the Preserve is the endangered Golden-cheeked Warbler (Setophaga chrysoparia). Visitors from all over the world come to the preserve to get a glimpse of this bird. Every spring this warbler species returns only to the Texas Hill Country to nest and raise young in nests made out of mature Ashe Juniper trees. Westcave Preserve provides the unique habitat required to sustain this species’ population. As part of a focused effort for avian research at the Preserve, our conservation staff joined with the City or Austin, and Travis County on their species-specific monitoring program of the Golden-cheeked Warbler. This includes surveys and banding of our warblers to keep track of their dispersal, survival rates, and their return rates.
Each breeding season, we conduct territory mapping, a technique that involves repeatedly surveying specific areas to track individual singing activity and movement patterns. This helps us estimate the number of breeding territories within the preserve. Following mapping, Westcave bands the visiting warblers, a careful process of safely capturing birds and applying lightweight, colored bands to their legs for individual identification. As part of the warbler conservation, staff also manage Brown-headed Cowbird populations, which pose a serious threat to Golden-cheeked Warblers and other songbirds during the breeding season. Cowbirds are brood parasites- they lay their eggs in other birds’ nests, often at the expense of the host species’ young. By dispatching cowbirds during this critical time, we help protect our native songbirds’ ability to successfully raise their own chicks.
Westcave is proud to be part of the Balcones Canyonlands Preserve (BCP)- a 33,000-acre network of protected lands managed through a multi-agency partnership. The BCP was created to conserve habitat for a number of endangered and threatened species, including the Golden-cheeked Warbler.