GPS tracking data reveals daily spatio-temporal movement patterns of waterfowl

• Published in: Movement Ecology
• Main Authors: Fiona McDuie, Michael L. Casazza, Cory T. Overton, Mark P. Herzog, C. Alexander Hartman, Sarah H. Peterson, Cliff L. Feldheim, Joshua T. Ackerman
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2019
• Subjects: Activity budgets; Animal movement; Contagion index; Energetics; Fine-scale movement; High frequency GPS; Biology (General); QH301-705.5; Pacific; Anas acuta
• Online Access: https://doi.org/10.1186/s40462-019-0146-8; https://doaj.org/article/21811535fea64fa9b18b54c82ff96b48

Abstract Background Spatio-temporal patterns of movement can characterize relationships between organisms and their surroundings, and address gaps in our understanding of species ecology, activity budgets, bioenergetics, and habitat resource management. Highly mobile waterfowl, which can exploit resources over large spatial extents, are excellent models to understand relationships between movements and resource usage, landscape interactions and specific habitat needs. Methods We tracked 3 species of dabbling ducks with GPS-GSM transmitters in 2015–17 to examine fine-scale movement patterns over 24 h periods (30 min interval), dividing movement pathways into temporally continuous segments and spatially contiguous patches. We quantified distances moved, area used and time allocated across the day, using linear and generalized linear mixed models. We investigated behavior through relationships between these variables. Results Movements and space-use were small, and varied by species, sex and season. Gadwall (Mareca strepera) generally moved least (FFDs: 0.5–0.7 km), but their larger foraging patches resulted from longer within-area movements. Pintails (Anas acuta) moved most, were more likely to conduct flights > 300 m, had FFDs of 0.8–1.1 km, used more segments and patches per day that they revisited more frequently, resulting in the longest daily total movements. Females and males differed only during the post-hunt season when females moved more. 23.6% of track segments were short duration (1–2 locations), approximately 1/3 more than would be expected if they occurred randomly, and were more dispersed in the landscape than longer segments. Distance moved in 30 min shortened as segment duration increased, likely reflecting phases of non-movement captured within segments. Conclusions Pacific Flyway ducks spend the majority of time using smaller foraging and resting areas than expected or previously reported, implying that foraging areas may be highly localized, and nutrients obtainable from smaller areas. ...