Amounts of white-tailed deer in winter: selection of site or pure coincidence?

In north-east North America, it has been often reported that white-tailed deer (Odocoileus virginianus Zimmermann) preferentially locate their winter yards along streams and lakes. However, it has never been determined if this pattern of habitat use was related to the distribution of coniferous stands associated with more humid, down slope sites along waterways or if deer preferentially use riparian stands in their winter yard. An experimental design to discriminate the effect of stream or lake proximity from other habitat features, was established in the lac des Baies deer yard, near Rimouski (eastern Quebec). Using pellet-group counts as an index of habitat use, the use of mature coniferous stands (3.75 ha balsam fir-northern white-cedar stands) contiguous to water (n = 8) was compared with similar fir-cedar stands (n = 8) located in the same deer yard but away (> 300 m) from streams or lakes. According to this index, riparian stands were used almost twice as much as the non-riparian stands (P = 0.02). Because of the similarity between the two groups of stands, neither the nature of the cover nor the nature of the shrub layer could explain this difference in use. Also, there was no evidence of a gradient in use according to distance in the first 150 m from the riparian ecotone. However, pellet-groups were particularly concentrated on small hillocks bordering the riparian zone. The exact cause for the greater use of riparian stands has not been established but could be related to an anti-predatory strategy, in this case, to habitats sought for bedding. In the context of the integrated forest management of winter deer yards, riparian stands should be given high priority as prime habitats for deer.