Abstracts

Presented by Jay A. VonBank - Email: jay.vonbank@students.tamuk.edu

Greater white-fronted geese (Anser albifrons frontalis) commonly wintered in the Gulf Coastal marshes of Texas and Louisiana before moving inland following agricultural expansion during the 1940s. During the last decade, white-fronted geese have further shifted their main wintering range northeastward into the Mississippi Alluvial Valley, presumably influenced by large-scale landscape modification and global climate change. Several regions in Texas and coastal Louisiana still support large populations during winter, but movements among these regions and contemporary wintering regions, and the timing of such movements during winter, are largely unknown. Land use varies dramatically among wintering regions, and there are likely differential region-specific energetic costs to wintering areas. Our research aims to determine the probability of movement among regions, and to compare energy expenditure among regions to understand drivers and consequences of the large-scale distribution shift. We used GPS/accelerometer tracking devices deployed on 97 white-fronts captured in Texas and Louisiana during winters 2016-2018. Mean daily movement distance was greatest in early winter and decreased as winter progressed, and was not influenced by daily temperature extremes. Of white-fronts tracked during winter 2016-2017 (n=62), 32.3% moved among wintering regions and 12.9% moved between the Central and Mississippi flyways. However, white-fronts marked earlier in winter, before 1 December (n=29), moved at greater rates among regions (37.9%) and flyways (44.8%). Among white-fronts tracked during winter 2017-2018 (n=55), 50.9% moved among regions and 14.5% moved between flyways, but white-fronts marked before 1 December (n=36) moved among regions (66.7%) and flyways (16.7%) slightly more than birds captured later in winter. Our analyses indicate that most large-scale movements among wintering regions and between flyways occur early in winter. Energy expenditure was greatest in rice producing regions in Texas and Louisiana. Addressing the role of movement and energy expenditure following a large-scale distribution shift will aid in the future management and conservation of white-fronted geese.