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Effective conservation of biological diversity on private lands will require changes in land-use policy and development practice. Conservation development (CD) is an alternative form of residential development in which homes are built on smaller lots and clustered together and the remainder of the property is permanently protected for conservation purposes. We assessed the degree to which CD is permitted and encouraged by local land-use regulations in 414 counties in the western United States. Thirty-two percent of local planning jurisdictions have adopted CD ordinances, mostly within the past 10 years. CD ordinances were adopted in counties with human population densities that were 3.0 times greater and in counties with 2.5 times more land use at urban, suburban, and exurban densities than counties without CD ordinances. Despite strong economic incentives for CD (e.g., density bonuses, which allow for a mean of 66% more homes to be built per subdivision area), several issues may limit the effectiveness of CD for biological diversity conservation. Although most CD ordinances required a greater proportion of the site area be protected than in a typical residential development, just 13% (n = 17) of the ordinances required an ecological site analysis to identify and map features that should be protected. Few CD ordinances provided guidelines regarding the design and configuration of the protected lands, including specifying a minimum size for protected land parcels or encouraging contiguity with other protected lands within or near to the site. Eight percent (n =11) of CD ordinances encouraged consultation with a biological expert or compliance with a conservation plan. We recommend that conservation scientists help to improve the effectiveness of CD by educating planning staff and government officials regarding biological diversity conservation, volunteering for their local planning boards, or consulting on development reviews., (© 2013 Society for Conservation Biology.)

Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges, a greater proportion of habitat within their range, greater habitat connectivity and a lower risk of extinction. Species with higher connectivity (i.e. less habitat isolation) also had a greater proportion of high-quality habitat, but had smaller, not larger, ranges, probably reflecting shorter distances between habitat patches for species with restricted distributions; such species were also more threatened, as would be expected given the negative relationship between range size and extinction risk. Fragmentation and connectivity did not differ among Carnivora families, and body mass was associated with connectivity but not fragmentation. On average, only 54.3 per cent of a species' geographical range comprised high-quality habitat, and more troubling, only 5.2 per cent of the range comprised such habitat within protected areas. Identification of global hotspots of fragmentation and connectivity will help guide strategic priorities for carnivore conservation.

The authors present findings from two landscape epidemiology studies of chronic wasting disease (CWD) in northern Colorado mule deer (Odocoileus hemionus). First, the effects of human land use on disease prevalence were explored by formulating a set of models estimating CWD prevalence in relation to differences in human land use, sex and geographic location. Prevalence was higher in developed areas and among male deer suggesting that anthropogenic influences (changes in land use), differences in exposure risk between sexes and landscape-scaled heterogeneity are associated with CWD prevalence. The second study focused on identifying scales of mule deer movement and mixing that had the greatest influence on the spatial pattern of CWD in north-central Colorado. The authors hypothesised that three scales of mixing - individual, winter subpopulation and summer subpopulation - might control spatial variation in disease prevalence. A fully Bayesian hierarchical model was developed to compare the strength of evidence for each mixing scale. Strong evidence was found indicating that the finest mixing scale corresponded best to the observed spatial distribution of CWD prevalence. This analysis demonstrates how information on the scales of spatial processes that generate observed patterns can be used to gain insight into the epidemiology of wildlife diseases when process data are sparse or unavailable.