Small mammal and habitat response to shoreline cottage development in central Ontario

Abstract

Changes in small mammal abundance and habitat caused by shoreline cottage development in central Ontario were studied in the summers of 1978 and 1979. This development significantly altered the vegetation composition and structure in the vicinity of cottages. These alterations, in turn, had an impact on small mammal abundance. These animals were classified in three response categories: tolerant (existing, at some level, regardless of degree of development), intolerant (extirpated at high levels of development), and indifferent to development. Tolerant species were the eastern chipmunk (Tamias striatus), short-tailed shrew (Blarina brevicauda), and deer mouse (Peromyscus maniculatus); intolerant species were the masked shrew (Sorex cinereus), red-backed vole (Clethrionomys gapperi), and woodland jumping mouse (Napeozapus insignis). The red squirrel (Tamiasciurus hudsonicus) was indifferent to development. Small mammal diversity was highest on mixed shorelines at moderate levels of development. Species diversity appeared to respond positively to vegetative composition, edge effect, and irregularity of habitat. These characteristics were all dependent on the level of cottage development.

Wildlife Responses to Urbanization: Patterns of Diversity and Community Structure in Built Environments

“…Urbanization is commonly considered an environmental disturbance (e.g., Blair and Launer 1997;Niemelä et al 2002;Zerbe et al 2003), yet it is in fact not a classical disturbance (e.g., like fire or flood) because people choose whether there is a return 7 Wildlife Responses to Urbanization to a predisturbance state and urban development shifts the system to a new condition, effectively resetting the parameters as to what is "normal" and what is "disturbed." Even so, an IDH pattern is manifested in cities as an increase in diversity as one moves away from the centrally developed urban core, through a heterogeneous mosaic of medium-density development and habitat remnants towards the urban fringe that supports native and nonnative species alike, with a decline in diversity outside the city limits (Racey and Euler 1982;Blair 1999;Marzluff 2005). c Dominance-diversity plots of relative abundance, where the X-axis represents species ranked in order of their abundance from common (near the origin) to rare (farther along the axis).…”

The Diet of the Eastern Screech-Owl, <em>Megascops asio</em>, at the Northern Periphery of its Range

“…With their small home ranges, rodents can thrive in disturbed suburban habitats (Dickman andDoncaster 1987, Nilon andVanDruff 1987); however, rodent diversity declines with increasing amount of impervious surface and bare ground (VanDruff and Rowse 1986). Like Meadow Voles, some other small mammal species such as the Northern Shorttailed Shrew (Blarina brevicauda) are most likely to occur at intermediate disturbance levels (Racey and Euler 1982) and in this study were only found at suburban sites. Small mammal abundance is often higher in small urban patches (Ekernas and Mertes 2006), a phenomenon that may be related to limited dispersal (Barko et al 2003).…”

“…As the House Mouse in North America is the commensal form that lives mostly in buildings (Banfield 1974), increased availability in suburbs is not surprising. Meadow Voles may be more common in suburban riparian parks than in riparian forest (Mahan and O'Connell 2005) and their density can increase with cottage development (Racey and Euler 1982). With their small home ranges, rodents can thrive in disturbed suburban habitats (Dickman andDoncaster 1987, Nilon andVanDruff 1987); however, rodent diversity declines with increasing amount of impervious surface and bare ground (VanDruff and Rowse 1986).…”

Biotic diversity interfaces with urbanization in the Lake Tahoe Basin

“…Positive responses to development were most common among species most closely associated with forest canopy (such as tree squirrels), whereas specialized ground associates (such as shrews) were not observed in areas with higher levels of development. Ants and small mammals showed peaks in richness or abundance at intermediate levels of development; others have observed such peaks in small mammals (Racey and Euler 1982) and ants (Nuhn and Wright 1979), as well as other taxonomic groups (McKinney 2002).…”