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Shrinking saline lakes provide irreplaceable habitat for waterbird species globally. Disentangling the effects of wetland habitat loss from other drivers of waterbird population dynamics is critical for protecting these species in the face of unprecedented changes to saline lake ecosystems, ideally through decision‐making frameworks that identify effective management options and their potential outcomes. Here, we develop a framework to assess the effects of hypothesized population drivers and identify potential future outcomes of plausible management scenarios on a saline lake‐reliant waterbird species. We use 36 years of monitoring data to quantify the effects of environmental conditions on the population size of a regionally important breeding colony of American white pelicans (Pelecanus erythrorhynchos) at Great Salt Lake, Utah, US, then forecast colony abundance under various management scenarios. We found that low lake levels, which allow terrestrial predators access to the colony, are probable drivers of recent colony declines. Without local management efforts, we predicted colony abundance could likely decline approximately 37.3% by 2040, although recent colony observations suggest population declines may be more extreme than predicted. Results from our population projection scenarios suggested that proactive approaches to preventing predator colony access and reversing saline lake declines are crucial for the persistence of the Great Salt Lake pelican colony. Increasing wetland habitat and preventing predator access to the colony together provided the most effective protection, increasing abundance 145.4% above projections where no management actions are taken, according to our population projection scenarios. Given the importance of water levels to the persistence of island‐nesting colonial species, proactive approaches to reversing saline lake declines could likely benefit pelicans as well as other avian species reliant on these unique ecosystems. [ABSTRACT FROM AUTHOR]

Many species of Procellaridae are nocturnal on their breeding grounds, exhibiting reduced activity during fuller moonlight, perhaps to avoid predation by predators that use the full moon to hunt after sunset. Among these nocturnal species, Streaked Shearwaters Calonectris leucomelas have high wing loading and have difficulty taking off--especially with unfavorable wind conditions--thus potentially exacerbating moonlight avoidance. Effects of moonlight and wind conditions on the colony activity of this species, however, is poorly understood. We investigated the phenomenon by counting the departure and arrival of birds, and measuring ambient light intensity, local wind speed, and local wind direction at a breeding colony of Streaked Shearwaters on Awashima Island, Japan. Moon phase and ambient light had no significant effect on the frequency of arrivals or departures. Frequency of departures decreased significantly with increasing wind speed, but no effect was seen on arrivals, and wind direction had no effect on arrivals or departures. Our results indicate that: (1) wind speed may play an important role in Streaked Shearwater takeoff from the colony, and (2) moonlight avoidance is a plastic trait that may diminish in large-bodied shearwaters when few diurnal aerial predators are present. [ABSTRACT FROM AUTHOR]

Climate change has been linked to distribution shifts and population declines of numerous animal and plant species, particularly in montane ecosystems. The majority of studies suggest both that low-elevation avian and small mammal species are shifting up in elevation and that high-elevation avian communities are either shifting further upslope or relocating completely with an increase in average local temperatures. However, recent research suggests numerous high elevation montane species are either not shifting or are shifting down in elevation despite the local increasing temperature trends, perhaps as a result of the increased precipitation at high elevations. In this study, we examine common vertebrate species distributions across the Hubbard Brook valley in the White Mountain National Forest, including resident and migratory songbirds and small mammals, in relation to historic spring temperature and precipitation. We found no directional change in distributions through time for any of the species. However, we show that the majority of low-elevation bird species in our study area respond to warm spring temperatures by shifting upslope. All bird species that shifted were long-distance migrants. Each low-elevation migrant species responded differently to warm spring temperatures, through upslope distribution expansion, downslope distribution contraction, or total distribution shift upslope. In contrast, we found a majority of high-elevation bird species and both high- and low-elevation mammal species did not shift in response to spring temperature or precipitation and may be subject to more complex climate trends. The heterogeneous response to climate change highlights the need for more comprehensive studies on the subject and careful consideration for appropriate species and habitat management plans in northeastern montane regions. [ABSTRACT FROM AUTHOR]