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Glacier Bay National Park, Alaska, is the ancestral homeland of the Huna Tlingit people, for whom Glaucous-winged Gull Larus glaucescens eggs were an important cultural food source until the 1960s, when the National Park Service (NPS) began to enforce regulations prohibiting harvest. Over the past 20 years, NPS has sponsored several studies as well as a Legislative Environmental Impact Statement to assess the cultural and biological impacts of egg harvests. Based on these findings, the US Congress passed legislation in 2014 authorizing harvest of Glaucous-winged Gull eggs in Glacier Bay National Park. With the long-awaited passage of this legislation, egg harvest may begin as soon as the NPS promulgates the necessary regulations and an annual harvest plan is developed. In preparation for egg harvest, we used ground- and vessel-based surveys to determine 1) the distribution and abundance of nesting gulls, 2) egg-laying phenology, 3) nesting vegetation, and 4) potential impacts of egg harvest on other species. During 2012-2015, we repeatedly surveyed 20 islands and sections of shoreline in Glacier Bay (that were likely colony locations based on historic observations) for gulls and found six potential egg-harvest colonies. The number of nests per colony ranged from 22 to 174. The number of nests at each colony remained consistent among years, whereas the number of eggs showed high interannual variability. Other species observed that could be affected by egg harvest included hauled-out marine mammals and other seabirds nesting nearby. The majority of nests (67%) were found in graminoid vegetation, an early successional state. This study marks the beginning of long-term monitoring of the population parameters to infer potential impacts of gull-egg harvest in Glacier Bay and to manage the harvest. In addition to yearly monitoring of productivity, research on nesting habitat shifts, food availability, and predation could improve the park's ability to understand any impacts of egg harvest on the distribution and abundance of Glaucous-winged Gulls in Glacier Bay National Park. [ABSTRACT FROM AUTHOR]

Human disturbance and climate change can impact populations by disrupting movement corridors and reducing important habitat. Characterizing how animals respond to such environmental changes is valuable for conservation as many species can experience reduced genetic diversity when deleterious habitat change occurs, leading to an increased likelihood of extirpation. Mountain goats (Oreamnos americanus) exemplify this conservation challenge; their geographically isolated habitat can inhibit gene flow, making them susceptible to population declines in the face of anthropogenic-induced change. To facilitate biologically informed population management of mountain goats in Glacier Bay National Park, Alaska, we characterized the fine-scale genetic population structure and examined how future climate change could impact population density. Our results indicated that three genetically distinct subpopulations exist in Glacier Bay and that the genealogical history is reflective of the historic landscape patterns. Climate modeling predicted that demographic productivity was likely to be reduced for all subpopulations; additionally, we found that climate change likely degrades the suitability of movement corridors that facilitate gene flow between subpopulations, ultimately increasing the cost of travel. Understanding such fine-scale patterns are key to managing subpopulations, particularly with impending changes to the landscape. [ABSTRACT FROM AUTHOR]