Conséquences de la chasse et des contraintes environnementales sur la démographie des populations d'ongulés. L'exemple du mouflon méditerranéen (Ovis gmelini musimon × Ovis sp.) en France et de l'élan (Alces alces) en Norvège.

Abstract : Several vertebrate populations have to face indirect and direct human pressures. Our aim here is to show how these pressures influence ungulate population dynamics beyond environmental factors commonly accounted for, such as habitat quality or climate. We present two case studies : Mediterranean mouflon (Ovis gmelini musimon × Ovis sp.) in France and moose (Alces alces) in Norway. We analyzed a long term study (30 years) of a mouflon population located in southern France (Hérault). Our study on moose was based on a transversal and comparative analysis of several populations inhabiting contrasted environments in Norway along a latitudinal gradient.

Our study on mouflon highlighted the advantages and limits of commonly used survey methods for ungulate population monitoring. We then showed that the dynamics of this population was influenced by (1) habitat closure, resulting from the reduction of pastoral activity, leading to the use of sub-optimal resources by mouflon, (2) selective hunting on trophy males, (3) the recent history of mouflon from which our population originated, (4) summer drought. These processes influence the dynamics of the mouflon through (1) a decrease in phenotypic quality as measured by body mass and trophy size (processes 1 and 2), (2) variation in reproductive output of females (processes 3 and 4), (3) and variation in lamb summer survival (process 4).

In moose, we showed that sexual size dimorphism (SSD) increases with increasing environmental seasonality, probably caused by higher resource quality when the growing season was short and intense. Selective hunting against males also shapes SSD by decreasing the proportion of adult males in the population. A low proportion of adult males could lead to a higher proportion of young males involved in reproduction, which in turn may have a negative impact on their body growth.

Based on two cases studies at different spatial scales, our results highlighted the existence of specific biological characteristics in harvested populations. In addition to the environmental constraints under which these populations evolve, we demonstrated that man can have a strong impact on their demography.
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Contributor : Mathieu Garel <>
Submitted on : Monday, February 26, 2007 - 9:40:42 AM
Last modification on : Monday, May 6, 2019 - 2:26:09 PM
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Mathieu Garel. Conséquences de la chasse et des contraintes environnementales sur la démographie des populations d'ongulés. L'exemple du mouflon méditerranéen (Ovis gmelini musimon × Ovis sp.) en France et de l'élan (Alces alces) en Norvège.. Interactions entre organismes. Université Claude Bernard - Lyon I, 2005. Français. ⟨tel-00133364⟩

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