Attempts to control predator numbers through spatially restricted culling typically faces a compensation process via immigration from surrounding source populations. To extend control effort to avoid this issue is in most instances impractical, both logistically and financially. Evidence-based strategy is therefore required to improve management practices. In close collaboration with local managers and hunters, we manipulated culling effort on red fox (Vulpes vulpes) over 5-6 years in 5 areas measuring 246 AE 53 km 2 . We estimated fox density in late February each year by spotlight counts with distance sampling and estimated reproductive performance by post-mortem examination of culled foxes. We then used mixed modeling to assess how culling rate (defined as foxes killed/foxes available) affected fox population growth from year to year, accounting for compensatory feedbacks. We found a strong compensatory density feedback acting through immigration, allowing red fox populations to resist high culling rates. Culling appeared ineffective at reducing late winter densities to below 25-32% of the estimated carrying capacity. On average, an annual culling rate equivalent to about 45% of the pre-breeding population was required to maintain density at 1 fox/ km 2 , given a carrying capacity of 1.5 foxes/km 2 , although there was considerable variation among sites. The required culling rate dropped to 25% if the culling could be performed during winter, after the fox dispersal period. In contrast, culling during the pre-dispersal breeding period was totally compensated for through immigration by the following February. Concentrating culling during the winter could improve the ability of practitioners to control year-to-year trends in fox numbers, taking into account site-specific carrying capacity. A winter strategy would also reduce the number of animals killed and hence the ethical and logistical costs of fox control, given limited financial and human resources. Our study illustrates how collaboration between local practitioners and scientists can make large-scale replicated management experiments achievable, leading to mutually approved guidelines. Ó 2015 The Wildlife Society.

Summary 1.Monitoring red fox Vulpes vulpes abundance is necessary to assess the status and management of this species and to understand predator-prey relationships. Spotlight counts are most often used for this purpose. However, comparisons between regions or over years may be questionable when using encounter rates, i.e. the number of foxes seen per kilometre. We evaluated whether distance-sampling methods, which take account of variation in visibility, could be applied to spotlight counts of foxes along roads and trails. 2. Distance-sampling methods were used at 12 contrasting sites in France in a systematic design with equally spaced transects or points. Line and point transects were simultaneously applied at two sites to find the more precise and efficient method. 3. The number of foxes seen near the centreline was always low, although some foxes may have been missed. A peak of sightings at subsequent intervals from the centreline suggested evasive movements. 4. Despite the low sighting frequency near the centreline, which may reflect a violation of distance-sampling assumptions, a good model fit was obtained for eight out of 12 data sets using a regular 50-m grouping of the distance data. Increasing the first interval to account for evasive movement improved model fit in the four other data sets. Density estimates ranged from 0·39 to 3·54 foxes km − 2 (range of coefficient of variation 4·5 -24·6%). 5.Point and line transects resulted in similar density estimates, but point transects were more time consuming and resulted in larger coefficients of variation due to a smaller number of foxes seen by this method. Line transects may therefore produce better estimates of fox numbers. 6. There were few differences among the effective strip width estimates between the 12 sites (range 191-286 m), thus line transect estimates may have a limited advantage over encounter rates. 7. Synthesis and applications. The systematic scheme we applied in this study improved sampling design and variance estimations and should be useful for surveying terrestrial mammals with spotlight counts. However, the location of transects along roads and in open habitats probably induced biased results. Methodological improvements are necessary before spotlight distance sampling can become a routine monitoring tool for foxes.

Given the problem of hybridization with domestic cats, there is a growing need to identify populations of the European wildcat Felis silvestris silvestris in order to protect the genetic integrity of this subspecies. In this paper, we use known locations of observations of wildcats or recovered carcasses to reassess the distribution of the wildcat in France and, in cases where carcasses were collected, we use both phenotypic and molecular genetic analyses to distinguish wildcats from hybrids with domestic cats. Spatially explicit multivariate analysis of wildcat' genotypes was then performed to define genetic units. Our study confirms the presence of wildcats in a large area of c. 155 000 km 2 , suggestive of a range of expansion, and divided into two clearly distinct and unconnected areas -the Pyrenees and the north-eastern part of France. However, European wildcat populations may be decreasing in the French Pyrenees, whereas the north-eastern part represents the main area (MA) of wildcat presence. This extension does not appear to be primarily due to hybrids, as both wildcats and hybrids were located throughout the MA. In addition, we found that genetic diversity of wildcats in the MA is remarkably high, suggesting that French populations are not threatened by a lack of genetic diversity. Furthermore, wildcats of the MA are structured into two genetically distinct populations that are contiguous and probably extend into Germany to form the largest area of wildcat presence in Europe and an area of major interest for their conservation. Our study calls for localized examination of the feasibility and usefulness of wildlife corridors to enhance connectivity between the different populations, thereby allowing sufficient levels of immigration and gene flow within the regional meta-population to ensure the long-term viability of these populations. Animal Conservation. Print ISSN 1367-9430 L. Say et al. Distribution and genetic structure in wildcat Animal Conservation 15 (2012) 18-27

Graphical abstract