Summary In recent decades, the Eurasian lynx Lynx lynx has recolonized former habitat, bringing it into potential conflict with livestock. We studied the spatial and temporal distribution of lynx attacks on sheep in the French Jura between 1984 and 1998, during and after its population expansion. We estimated the local and regional impact of lynx predation on livestock. The number of attacks increased from three in 1984 to 188 in 1989, concurrently with the colonization of the main sheep range by lynx. During subsequent years, 66–131 attacks were recorded annually (92–194 sheep killed per year). On average, 1·6 sheep were killed per attack. Lynx preyed disproportionately on lambs and subadult sheep. A small percentage of flocks (9·5–22·9%) were attacked, most of which (75·2%) were attacked once or twice a year. At the regional level, annual sheep losses to lynx were 0·14–0·59% of the total number of sheep. The major lynx–livestock problem was due to clustered attacks in a few small areas. Each year, two to six ‘hot spots’ (33–69% of the attacks) were identified. Hot spots covered 0·3–4·5% of the total area where attacks occurred (1835–4061 km2). Roe deer abundance was higher in hot spots and, even here, sheep only made up 3·1% of the lynx diet. These data show that lynx were not killing sheep due to shortages of alternative prey or in response to an increased need for food when rearing young. The concentration of hot spots in only nine small areas between 1984 and 1998 indicated that only a few individual lynx were involved. The reappearance of hot spots at the same sites, after years of interruption and despite the removal of lynx, suggested that the ultimate factors causing hot spots were factors inherent to those sites. Further investigation is needed to identify causal factors with a view to eliminating them. These may relate to landscapes features, animal husbandry practices or the behavioural ecology of lynx. In future, where large predator reintroductions are planned, the potential for concentrated, localized, impact should be evaluated and mitigation measures put in place. For scattered and episodic lynx damage, financial compensation is the only realistic option at present. In hot spots, the cost‐effectiveness of guard‐dogs or the selective removal of some individual lynx should be evaluated.

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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.

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