Keywords
mahalanobis distances factor analysis, presence-only models, distributions, cranes, winter feeding
Start Date
1-7-2010 12:00 AM
Abstract
Winter feeding has become a critical approach to sustain animals in high latitude,but little literature has investigated possible side-effects in terms of ecological niches. Toexplore whether winter feeding might affect species distributions at regional scale, weemployed a novel spatial model, Mahalanobis Distances Factor Analysis, in the case ofRed-crowned Cranes (Grus japonensis) in Hokkaido, Japan. This model features betterprediction ability with more explicit ecological significance compared to conventionalmethods. Furthermore, particularly innovative is that axes are used to define ecologicalniches, with a minimal set of habitual variables to calculate habitat suitability in thealgorithm. In results, winter feeding seemed to considerably impact the distributions,suggesting heavy dependence of human food supplies of the focal species. Besides, most ofthe other human influence variables, such as human population and road, tended to berelatively less associated with the occurrence localities, implying decreased sensitivity tohuman proximity. Taken together, the focal species might possibly survive in the adverseclimate at the cost of diminished innate ability. In other words, winter feeding could impairthe ability of self-sustaining in the wilderness, which can also take place but may remainhidden in similar cases around the globe. Contingency plans should thus be considered tominimize the side-effects of winter feeding for effective biodiversity conservation.
Unexpected Side-effects of Winter Feeding: Learning from Mahalanobis Distances Factor Analysis in the case of Red-crowned Cranes in Hokkaido, Japan
Winter feeding has become a critical approach to sustain animals in high latitude,but little literature has investigated possible side-effects in terms of ecological niches. Toexplore whether winter feeding might affect species distributions at regional scale, weemployed a novel spatial model, Mahalanobis Distances Factor Analysis, in the case ofRed-crowned Cranes (Grus japonensis) in Hokkaido, Japan. This model features betterprediction ability with more explicit ecological significance compared to conventionalmethods. Furthermore, particularly innovative is that axes are used to define ecologicalniches, with a minimal set of habitual variables to calculate habitat suitability in thealgorithm. In results, winter feeding seemed to considerably impact the distributions,suggesting heavy dependence of human food supplies of the focal species. Besides, most ofthe other human influence variables, such as human population and road, tended to berelatively less associated with the occurrence localities, implying decreased sensitivity tohuman proximity. Taken together, the focal species might possibly survive in the adverseclimate at the cost of diminished innate ability. In other words, winter feeding could impairthe ability of self-sustaining in the wilderness, which can also take place but may remainhidden in similar cases around the globe. Contingency plans should thus be considered tominimize the side-effects of winter feeding for effective biodiversity conservation.
