NOTE: This item is not available outside the Texas A&M University network. Texas A&M affiliated users who are off campus can access the item through NetID and password authentication or by using TAMU VPN. Non-affiliated individuals should request a copy through their local library's interlibrary loan service.
Factors contributing to nest predation within habitat of the Golden-checked Warbler, Travis County, Texas
Abstract
Nest failure is considered an important factor contributing to the decline of Golden-cheeked Warblers (Dendroica chrysoparia), yet relatively little is known of the extent of nest predation on this species. In April 1994 and 1995, 1 placed artificial nests, simulating those of Golden-cheeked Warblers, along 200 transacts at 5 study sites in Travis County, Texas. This study was designed to determine if differential levels of predation existed between nests placed in forest interior tracts or near habitat edges. A total of 508 of 794 nests (64%) was depreciated. In all but one of the four trials, edge nests had depredation greater than interior nests; however, only the first trial of 1994 had a statistically significant difference (P = 0.04). There does not seem to be a greater level of nest predation at the 10-m habitat edge than in the 100-m habitat interior. Predation levels seemed to vary with site location in the county, suggesting local habitat features may have contributed to predation levels to a greater extent than nest proximity to a habitat edge. Overall habitat-patch size also may contribute to levels of nest predation, as the largest two study sites had the lowest levels of nest predation. However, habitat-patch size did not correlate significantly with the level of nest predation for either year of my study. Avian predator abundance varied significantly (P = 0.001) among study sites, but failed to explain differences in predation levels among sites. Using a remotelytriggered camera stationed at an artificial nest, I identified three nest predators: Western Scrub-Jay (Aphelocoma californica), Blue Jay (Cyanocitta cristata), and Texas rat snake (Elaphe obsolete). The results I present should be interpreted with caution. With few data on actual levels of predation on Golden-cheeked Warbler nests, comparison of the level of predation on my artificial nests to actual levels of predation remains difficult. Predation rates on my nests may relate more to the technique I applied than to actual rates of predation on Golden-cheeked Warbler nests. Further study of factors contributing to levels of nest predation in Golden-cheeked Warbler habitat is needed before drawing conclusions from these data.
Description
Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references: p. 75-85.
Issued also on microfiche from Lange Micrographics.
Collections
Citation
Fink, Mark Lewis (1996). Factors contributing to nest predation within habitat of the Golden-checked Warbler, Travis County, Texas. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1996 -THESIS -F56.
Request Open Access
This item and its contents are restricted. If this is your thesis or dissertation, you can make it open-access. This will allow all visitors to view the contents of the thesis.