Small mammals of Point Pelee National Park: Protecting biodiversity in small reserves (Ontario)

Habitat destruction, fragmentation and degradation have been widespread throughout southern Ontario with devastating effects on wetlands. Small reserves are all that in this highly agricultural/urban landscape to protect the biodiversity of Great Lakes Marsh and Carolinian Forest ecosystems. Small reserves are vulnerable to species loss through a host of problems related to size and as a result, the value of small reserves to conservation strategies has often been questioned. Indicator species can be used as a means of studying the conditions of complex ecosystems. In this research, small mammals were sampled in the wetlands of Point Pelee National Park as a method of assessing the condition of the Great Lakes ecosystem contained within a small, disturbed reserve. Live-trapping studies were run during the summer of 1995-96. During 1995, transects throughout the marsh and associated wetlands produced baseline data concerning the wetland ecologies of small mammals at Point Pelee National Park. During 1996, grid studies enabled a more detailed studied of population dynamics and home range characteristics of species in the marsh and swamp thicket regions of the Park. Data collected during the 1995-96 field seasons were used to characterize small mammal communities of the wetlands of Point Pelee National Park. The presence and distribution of eight species of small mammals was documented in the wetlands of the Park. The status of Pelee’s small mammal communities was assessed by comparison with past surveys and studies in the literature. Wetland habitats were found to support greater species richness and species diversity than dryland regions of the Park. The field surveys indicate that no native species have been lost since 1971. Further, no exotic mammal species were trapped. Generally, Pelee’s small mammal species assemblages and species richness are typical of regional and undisturbed sites. Population trends and home range characteristics were similar to those reported in the literature. Essentially, the condition of Pelee’s small mammal communities approximates relatively undisturbed conditions. The current status of small mammal communities at Point Pelee National Park seems to be indicative of two conditions. First, the adoption of ecosystem principles and subsequent restorative measures have allowed Park ecosystems to move towards a recovery condition. Secondly, small mammal communities are inherently resilient to changes in the environment and can recover in time from the effects of disturbance. Further, it seems that Pelee is adequate in terms of size to effectively maintain viable small mammal populations. This research contributes knowledge in three main ways. First, this research suggests that species assemblages and species diversity of small mammal communities may be used as indicators of general ecosystem health. Secondly, wetlands are important as habitat for small mammals. Thirdly, small reserves are important in the protection of biodiversity, especially in highly modified landscapes