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Managers need information about the vulnerability of historical plant communities, and their potential future conditions, to respond appropriately to landscape change driven by global climate change. We model the climate envelopes of plant communities on the Kenai Peninsula in Southcentral Alaska and forecast to 2020, 2050, and 2080. We assess 6 model outputs representing downscaled climate data from 3 global climate model outputs and 2 representative concentration pathways. We use two lines of evidence, model convergence and empirically measured rates of change, to identify the following plausible ecological trajectories for the peninsula: (1.) alpine tundra and sub-alpine shrub decrease, (2.) perennial snow and ice decrease, (3.) forests remain on the Kenai Lowlands, (4.) the contiguous white-Lutz-Sitka spruce complex declines, and (5.) mixed conifer afforestation occurs along the Gulf of Alaska coast. We suggest that converging models in the context of other lines of evidence is a viable approach to increase certainty for adaptation planning. Extremely dynamic areas with multiple outcomes (i.e., disagreement) among models represent ecological risk, but may also represent opportunities for facilitated adaptation and other managerial approaches to help tip the balance one way or another. By reducing uncertainty, this eclectic approach can be used to inform expectations about the future. [ABSTRACT FROM AUTHOR]

Rapidly changing environmental conditions are influencing distributions of wildlife species in Alaska. Due to strict physiological requirements, the distribution of American martens (Martes americana) is theorized to be driven by changing habitat, climate, and other anthropogenic conditions. We aimed to quantify marten distributions on the Kenai Peninsula, Alaska, and compared historic and contemporary occurrence records. To illustrate changing distribution patterns, we developed predictive niche models for 2 decades and investigated patterns by relating environmental trends with predicted distributions. Museum and trapping records, supplemented by aerial videography detections for martens on the Kenai over the past century, served to train Random Forests based niche models for 1988-2001 and 2002-2010. Change-detection analyses revealed an ongoing westward expansion of likely marten distribution on the Kenai Peninsula since at least 1988, and historic records indicated longer-term growth. Top predictors in the models included soil ecotype, landcover, distance to trails, and distance to recreation sites. Our research suggests that on the Kenai Peninsula, marten distribution is responding to a combination of landscape and climate effects that have contributed to expanding marten distributions over the past century. [ABSTRACT FROM AUTHOR]