The Trade-off Between Housing Density and Sprawl Area: Minimizing Impacts to Carabid Beetles (Coleoptera: Carabidae)

Increasing housing density has negative effects on native biodiversity. This implies that we should build at low density to conserve native species. However, for a given human population, low-density development must cover a large area, resulting in sprawl. A pertinent question is then, at what housing density are the impacts of a given human population on native biodiversity minimized? We addressed this question with carabid beetles in Ottawa and Gatineau, Canada. First, we collected beetles at 22 sites representing a range of housing densities. We then used these data to estimate beetle abundance and species richness in hypothetical development scenarios representing the housing density/sprawl area trade-off. Our results suggest that clustering development at a high housing density minimizes the impacts of a given human population on carabid beetles. If these results are general across all forest taxa, then planning that favors densification rather than sprawl would minimize urbanization effects on forest biodiversity.