Explaining the successful introduction of the alpine marmot in the Pyrenees

López B.C., Pino J., López A. (2010) Explaining the successful introduction of the alpine marmot in the Pyrenees. Biological Invasions. 12: 3205-3217.
Link
Doi: 10.1007/s10530-010-9712-0

Abstract:

Alpine marmots were introduced into the northern Pyrenees between 1948 and 1988 from individuals captured in the French Alps, in order to bolster food sources for the golden eagle and brown bear. The marmot's subsequent occupation of the southern Pyrenees has been extremely fast. From an initial population of ~400 individuals, the present population in the southern Pyrenees is estimated to be of more than 10,000 individuals. The objective of this study was to assess what were the mechanisms that have enabled such a fast occupation of the territory. We studied habitat preferences and habitat selection of the alpine marmot in the southern Pyrenees both at the micro- and meso-scale, and compared our results with similar data in the bibliography on their native region. We also compared climatic data from both the native and introduction sites. Our results indicate relatively low climate (precipitation and temperature) matching between the two sites but a relatively high habitat matching. Marmots negatively select high woody cover and the presence of conifers in their home range, while they choose alpine and sub-alpine meadows close to rivers with boulders. Furthermore, the marmot population is independent of snow cover duration. We conclude that the successful establishment in the Pyrenees by the alpine marmot is explained both by the habitat- and climate-matching mechanisms. In both aspects, marmots show a generalist response. Meso-scale GIS-derived variables were non significant when analyzed together with local, micro-scale variables from field measurements. © 2010 Springer Science+Business Media B.V.

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Potential distribution of the alpine marmot in Southern Pyrenees

López B.C., Figueroa I., Pino J., López A., Potrony D. (2009) Potential distribution of the alpine marmot in Southern Pyrenees. Ethology Ecology and Evolution. 21: 225-235.
Link
Doi: 10.1080/08927014.2009.9522477

Abstract:

Alpine marmots were introduced in the French Pyrenees between 1948 and 1988. The exact number of re-introduced individuals is unknown, but it oscillated around 400. The likely preference of marmots for the southern sunny slopes rapidly facilitated their expansion to the southern Pyrenees, where the lack of both natural predators and of important interspeciflc competitors also likely facilitated an important expansion of this species. There is only one attempt to broadly calculate the population of marmots in the southern Pyrennes, estimating a population of around 10,000 individuals. However, there exist no reliable data to calculate the potential distribution of this new colonizing species in the southern Pyrenees, and a map of the potential distribution of the species is necessary to see whether alpine marmots can potentially establish in sites where it might be necessary to manage its populations for various reasons. We developed a map of potential distribution based on census carried out in summer of 2007 in an area of more than 600 km. We censused more around 300 colonies together with around 300 random points to characterized habitat selection variables. A map with a pixel size of 15 × 15 m has been obtained based on preferred habitats and also on distances to other habitats for the whole southeastern Pyrenees.

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