The European rabbit (Oryctolagus cuniculus) is a key prey species for most Mediterranean predators in the Iberian Peninsula, including some endangered species such as the Iberian lynx (Lynx pardinus). Rabbit populations in the Iberian Peninsula have collapsed since the arrival of rabbit haemorrhagic disease (RHD) in the late 1980s. We studied the dietary and numerical responses of five species of mammalian carnivores to this decline in the Doñ ana National Park (south-west Spain), where RHD arrived in 1990. Behavioural responses of the Iberian lynx, a rabbit specialist, were also studied through radio-tracking. All carnivores reduced rabbit intake with decreasing rabbit densities immediately after the initial RHD outbreak, though the level of reduction varied among species. Reductions in rabbit consumption were highest for the Eurasian badger (Meles meles) and the red fox (Vulpes vulpes), low for the genet (Genetta genetta) and mongoose (Herpestes ichneumon), and negligible for the Iberian lynx, thus confirming its strong dependence on rabbits for survival. The Iberian lynx social system was temporarily altered. Female lynxes increased their home range size and no subadult lynxes dispersed in the year following the rabbit crash, causing a temporal local increase of lynx density, which returned to previous values a year after the arrival of RHD. The red fox showed a negative numerical response, reducing its abundance following the rabbit decline. Despite the fact that rabbit consumption was reduced in most carnivores, the role of joint predation is discussed as a factor in the failure of rabbit recovery after this new disease.

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The lesser grison (Galictis cuja), a poorly known mustelid of southern South America, has been described as a catholic feeder living close to water. Consequently, the potential exists for competition with the recently introduced American mink (Mustela vison). Nonetheless, like most ferrets the lesser grison can be a specialized mammal hunter, in which case it could benefit from introduced mammalian prey (the European hare, Lepus europaeus, and European rabbit, Oryctolagus cuniculus). The diet and trophic position of the lesser grison in Argentinean Patagonia are described in order to discuss the potential effects of introduced mammalian species on grison populations. Mammals (mainly native rodents and introduced lagomorphs) occurred in 100% of the feces and represented 95% of the biomass consumed. In one site, European hares and rabbits reached a combined 66% of biomass consumed, whereas in the other site rabbits were scarce or absent and lagomorphs represented 35% of the biomass consumed. We postulate that lesser grison populations in Patagonia have benefited from the introduced lagomorphs. On the other hand, lesser grisons frequently occupied river valleys, but did not rely on aquatic or semiaquatic prey. Hence, hunting-habitat preference segregates this mustelid from the American mink (Mustela vison), which consumes a catholic diet in which aquatic species usually predominate.

In this paper we show how new technologies can be incorporated from the gathering of field data on wildlife distribution to the final stage of producing distribution maps. We describe an integrated framework for conducting wildlife censuses to obtain data to build predictive models of species distribution that when integrated in a GIS will produce a distribution map. Field data can be obtained with greater accuracy and at lower costs using a combination of Global Positioning System, Personal Digital Assistant, and specific wildlife recording software. Sampling design benefits from previous knowledge of environmental variability that can be obtained from free remote sensing data. Environmental predictors derived from this remote sensing information alone, combined with automatic procedures for predictor selection and model fitting, can render cost‐effective predictive distribution models for wildlife. We show an example with guanaco distribution in the Patagonian steppes of Santa Cruz province, Argentina.