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Abstract AimIdentifying how climate change, habitat loss, and corridors interact to influence species survival or extinction is critical to understanding macro‐scale biodiversity dynamics under changing environments. In North America, the ice‐free corridor was the only major pathway for northward migration by megafaunal species during the last deglaciation. However, the timing and interplay among the late Quaternary megafaunal extinctions, climate change, habitat structure, and the opening and reforestation of the ice‐free corridor have been unclear. LocationNorth America. Time period15–10 ka. Major taxa studiedWoolly mammoth (Mammuthus primigenius). MethodsFor central North America and the ice‐free corridor between 15 and 10 ka, we used a series of models and continental‐scale datasets to reconstruct habitat characteristics and assess habitat suitability. The models and datasets include biophysical and statistical niche models Niche Mapper and Maxent, downscaled climate simulations from CCSM3 SynTraCE, LPJ‐GUESS simulations of net primary productivity (NPP) and woody cover, and woody cover based upon fossil pollen from Neotoma. ResultsThe ice‐free corridor may have been of limited suitability for traversal by mammoths and other grazers due to persistently low productivity by herbaceous plants and quick reforestation after opening 14 ka. Simultaneously, rapid reforestation and decreased forage productivity may have led to declining habitat suitability in central North America. This was possibly amplified by a positive feedback loop driven by reduced herbivory pressures, as mammoth population decline led to the further loss of open habitat. Main conclusionsDeclining habitat availability south of the Laurentide Ice Sheet and limited habitat availability in the ice‐free corridor were contributing factors in North American extinctions of woolly mammoths and other large grazers that likely operated synergistically with anthropogenic pressures. The role of habitat loss and attenuated corridor suitability for the woolly mammoth extinction reinforce the critical importance of protected habitat connectivity during changing climates, particularly for large vertebrates.
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Connectivity and conservation of Western Chimpanzee ( Pan troglodytes verus ) habitat in Liberia
Abstract AimAs part of the Gaborone Declaration for Sustainability in Africa, Liberia has pledged to include the value of nature in national decision making through natural capital accounting. Surveying species of concern, such as the western chimpanzee (Pan troglodytes verus), which was recently reclassified as “critically endangered” by the International Union for Conservation of Nature, and identifying protection priority areas are critical first steps towards achieving Liberia's goal to conserve 30% of its remaining forests and supporting the wave of conservation projects taking place in the country. LocationLiberia, Africa. MethodsWe modelled western chimpanzee habitat suitability, focusing on determining relevant environmental predictors and the most appropriate scale for modelling species–habitat relationships. We built models at six resolutions (30–960 m) to identify scale domains where relationships remain constant. We include several habitat variables that have not been included in prior modelling efforts. We then used the suitability map as the conductance input into a connectivity analysis using Circuitscape. ResultsThe amount of forest within 1–3 km was the most important predictor of chimpanzee occurrence. Variable ranks and importance shifted considerably between modelling scales, supporting the need for multiscale investigations, but scale domains were present. Several important corridors for chimpanzee habitat and movement overlap considerably with existing timber and palm oil concessions and overlap mining and rubber concessions to a lesser degree. Main conclusionsThe proportion of primary forest within 1–3 km is critically important for chimpanzee habitat. Ongoing conservation projects and efforts taking place in Liberia including the Good Growth Partnership and the Gaborone Declaration for Sustainability in Africa can utilize the spatial findings on connectivity provided by this study to inform future conservation decisions, particularly expanding exiting protected areas.
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- Award ID(s):
- 1934759
- PAR ID:
- 10450726
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Diversity and Distributions
- Volume:
- 27
- Issue:
- 7
- ISSN:
- 1366-9516
- Page Range / eLocation ID:
- p. 1235-1250
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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