Although habitat fragmentation has been widely implicated in the decline of some large mammals, we found little explicit documentation of overall mammal community response to fragmentation of regional wetland resources. Although individual mammals, being highly mobile, can disperse to new areas having the proper combination of wetland types at a sufficient density, they probably do so at risk of greater predation and energetic loss. For example, Brooks et al. However, home range sizes can vary greatly by season and habitat type. Methods for surveying mammal communities are described in Cooperrider et al.
Mammals occur in wetlands throughout the year.
Mammal density and richness may be reduced during and immediately after floods in riverine wetlands. Surveys covering several wetlands, if not conducted simultaneously, should occur within consecutive days, unless severe weather conditions intervene. Diurnally, detection of most species is greatest at night. Visual surveys of larger, day-active species can be conducted from ground level, from elevated observation posts, or aerially. Low-altitude overflights or aerial photography can be used to identify some beaver dams and beaver and muskrat lodges, and to census moose and large mammals in open country.