2025/08/04 by Holly M. Todaro, Zoe E. Protzman, Lindsey M. Buehler +1 · 1 voice
Environmental Science · #Avian ecology and behavior #Biology #Ecology #Environmental science #Fish Ecology and Management Studies #Fishery #Geography #Habitat #Marine and fisheries research #Occupancy #Shrike
paper · doi:10.1080/15594491.2025.2535093
openalex publication_date 2025/08/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Accurate occupancy estimates are valuable for conservation planning and effective habitat management. Various methods are used to collect occupancy data on passerines, including audio recording units, driving transects, passive netting, and, most commonly, point count surveys. These methods are often time-intensive and may be insufficient when surveying species with a large territory like raptors, or even passerines, such as the near-threatened Loggerhead Shrike (Lanius ludovicianus). This is because stationary surveys may only capture a small portion of territories and thus under-estimate occupancy. Acknowledging the potential limitations of point count methodology, we investigated whether camera traps could be an effective tool for estimating occupancy of Loggerhead Shrikes. To compare the efficacy of these two survey methods, we used an occupancy modeling framework to analyze 1 year of Loggerhead Shrike detection data that were opportunistically collected from breeding bird point count surveys and camera traps at a grassland-sagebrush ecotone in northeast Wyoming, USA. From 2022 to 2023, camera traps detected Loggerhead Shrikes 62 times, with at least one observation at 18 out of 29 cameras (naïve occupancy = 0.62). The greatest number of observations occurred in the months of July and August. In contrast, point count surveys conducted each May yielded only four detections on 26 transects (naïve occupancy = 0.18) in 2022. Distance to nearest tree (i.e. perch proximity), rainfall, and altered camera viewshed influenced the detection rate of Loggerhead Shrikes with camera traps. Our research offers promising avenues for future studies using camera trap methodology, which can significantly reduce field labor and may be advantageous for detecting elusive species such as the Loggerhead Shrike and for assessing habitat use outside the breeding season (e.g. prospecting). However, further research is needed to validate its effectiveness in accurately estimating occupancy.