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Abstract ContextShifts in climate and land use have dramatically reshaped ecosystems, impacting the distribution and status of wildlife populations. For many species, data gaps limit inference regarding population trends and links to environmental change. This deficiency hinders our ability to enact meaningful conservation measures to protect at risk species. ObjectivesWe investigated historical drivers of environmental niche change for three North American weasel species (American ermine, least weasel, and long-tailed weasel) to understand their response to environmental change. MethodsUsing species occurrence records and corresponding environmental data, we developed species-specific environmental niche models for the contiguous United States (1938–2021). We generated annual hindcasted predictions of the species’ environmental niche, assessing changes in distribution, area, and fragmentation in response to environmental change. ResultsWe identified a 54% decline in suitable habitat alongside high levels of fragmentation for least weasels and region-specific trends for American ermine and long-tailed weasels; declines in the West and increased suitability in the East. Climate and land use were important predictors of the environmental niche for all species. Changes in habitat amount and distribution reflected widespread land use changes over the past century while declines in southern and low-elevation areas are consistent with impacts from climatic change. ConclusionsOur models uncovered land use and climatic change as potential historic drivers of population change for North American weasels and provide a basis for management recommendations and targeted survey efforts. We identified potentially at-risk populations and a need for landscape-level planning to support weasel populations amid ongoing environmental changes.
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Long‐Term Human Land‐Use Change Throughout Southeast Asia Reshapes the Distribution of Suitable Habitat for a Human‐Commensal Bird Species
ABSTRACT Human activity has reshaped ecological communities for thousands of years. While these activities have typically led to habitat loss, some species have successfully exploited human environments. However, the effects of long‐term human land‐use on the distributions of such species are poorly understood. Here, we investigated how land‐use change over the last 12,000 years has altered habitat distributions for a widespread human‐commensal bird, the Pacific swallow (Hirundo tahitica). LocationSoutheast Asia, Melanesia. MethodsWe assessed habitat availability for Pacific swallows using citizen science‐based occurrence records and species distribution models that included (a) only climate data, (b) only land‐use data and (c) both variable sets combined. We evaluated approaches to address the unique spatial biases that arise in unstructured survey data of human‐associated species and determined which models performed best with present‐day occurrence records. We then hindcasted alternative models at 1000‐year intervals over 12,000 years to evaluate the relative effects of climate and human land‐use on long‐term habitat availability. ResultsModels that included both climate and human land‐use variables were the best fit to occurrence records. Standard methods for controlling for spatial bias performed poorly compared with fully sampling the environmental background, highlighting unique considerations for modelling human‐associated species. Hindcasting showed that while climate‐only models predicted little change in habitat availability over time, combined models showed habitat increases beginning more than 5000 years ago and significant expansions of habitat over the last 2000 years. Main ConclusionsHuman land‐use over the last several thousand years has likely provided Pacific swallows with substantial new habitat, which may have led to population size expansions. Incorporating long‐term human land‐use into species distribution models offers insights into when associations with human environments may have arisen and generates testable predictions for how populations respond and adapt to human land‐use change over millennial timescales.
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- Award ID(s):
- 1947306
- PAR ID:
- 10685977
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Biogeography
- Volume:
- 52
- Issue:
- 6
- ISSN:
- 0305-0270
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/jbi.15123
