| Titre : | Density influences accuracy of model-based estimates for a forest songbird (2019) |
| Auteurs : | Lisa O'Donnell, Auteur ; C. Craig Farquhar, Auteur ; Jason W. Hunt, Auteur ; Kelly Nesvacil, Auteur ; Jennifer L. Reidy, Auteur ; William Reiner, Auteur ; Jonathan L. Scalise, Auteur ; Christopher C. Warren, Auteur |
| Type de document : | Article |
| Dans : | Journal of Field Ornithology (90(1) April, 2019) |
| Article en page(s) : | 80-90 |
| Mots-clés: | Balcones Canyonlands Preserve ; Golden-cheeked Warbler ; Setophaga chrysoparia ; color banding ; endangered species ; intensive territory monitoring ; model validation ; point count ; territory mapping |
| Résumé : | Golden-cheeked Warblers (Setophaga chrysoparia) are endangered songbirds that breed exclusively in the Ashe juniper (Juniperus ashei) and oak (Quercus spp.) woodlands of central Texas. Despite being the focus of numerous studies, we still know little about the size of the range-wide breeding population and how density varies across the spectrum of juniper co-dominated woodlands. Models that have been tested and shown to be accurate are needed to help develop management and conservation guidelines. We evaluated the accuracy and bias of density estimates from binomial mixture models, the dependent double-observer method, and distance sampling by comparing them to actual densities determined by intensive territory monitoring on plots in the Balcones Canyonlands Preserve, Austin, Texas. We found that the binomial mixture models consistently overestimated density by 1.1–3.2 times (actual density = 0.07–0.46 males/ha), and the other two models overestimated by 1.1–29.8 times at low density and underestimated by 0.5–0.9 times at high density plots (actual density = 0.01–0.46 males/ha). The magnitude of error for all models was greatest at sites with few or no birds ( |
| En ligne : | https://onlinelibrary.wiley.com/doi/abs/10.1111/jofo.12116 |



