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Habitat sinks can attract dispersing animals if high mortality or breeding failure are difficult to detect (e.g., when due to human hunting or pollution). Using a simple deterministic model, we explore the dynamics of such source-sink systems considering three scenarios: an avoided sink, no habitat preference, and an attractive sink. In the second two scenarios, there is a threshold proportion of sink habitat above which the whole population decreases to extinction, but this extinction threshold varies with habitat preference and the relative qualities of the two habitat types. Hence, it would be necessary to know the habitat preferences of any species in a source-sink system to interpret data on population increases and declines. In the attractive sink scenario, small changes in the proportion of sink habitat may have disproportionate effects on the population persistence. Also, small changes in growth rates at the source and the sink severely affect the threshold and the time of extinction. For some combinations of demographic parameters and proportion of habitat sink, the decline affects the source first; thus, during some time, it will be hidden to population monitoring at the sink, where numbers can even increase. The extinction threshold is also very sensitive to the initial population sizes relative to carrying capacity. Attractive sinks represent a novel aspect of source-sink dynamics with important conservation and management implications.

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We report a case of bacteremia associated with hemorrhagic bullous skin lesions on the leg caused by non-01, non-0139 Vibrio cholerae in a 66-year-old man with hemochromatosis developed in an inland region. The organism was isolated from blood and bullae fluid. The patient was treated successfully with cefotaxime and doxycycline. This report emphasizes the potential of this organism to produce bacteremic cellulitis in people with underlying illness in the absence of usual epidemiological risk factors.

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We used path analysis to investigate the causal relationships between Iberian lynx and Egyptian mongoose track numbers, and to estimate the direct effect of the former on the latter in the Doñana area (2750 km(2) ), south-western Spain. Relative abundance of rabbits, shrub cover and protection level were also considered in the path analysis. An observational study consisting of a repeated track survey with a split-plot design was also carried out between 1990 and 1996 to independently test the results obtained by path analysis. Maximum likelihood ratio tests of the goodness-of-fit of the model to the data and other indices used all indicated that the proposed theoretical model depicting the relationships among variables was adequate. Egyptian mongooses suffered a significant direct negative effect from lynx, and rabbits and protection level positively, and significantly affected lynx track abundance; rabbits were also significantly affected by shrub cover (all these standardized partial correlation coefficients ranged from 0.34 to 0.41). Shrub cover did not directly affect either lynx or mongoose tracks. Relatively important indirect effects were found between shrubs and lynx (0.12), and between rabbits and mongooses (-0.14), and protection and mongooses (-0.17). The two latter non-intuitive indirect effects were through the lynx path, as a consequence of the negative direct influence of lynx on mongooses. The repeated track censuses confirmed that lynx presence significantly affects number of mongoose tracks. In areas without lynx, mean number of mongoose tracks were 3.6 times higher than in areas with lynx. It remains an interesting question which of several proposed hypotheses explains co-existence of both species in south-western Spain.

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A combination of the dissociative anesthetic ketamine hydrochloride (KH) and the sedative xylazine hydrochloride (XH) was used to immobilize 31 wild Iberian lynx (Felis pardina) 45 times at Doñana National Park, Spain. A mean (+/- SE) dose of 4.6 (+/- 0.2) mg/kg KH and 4.0 (+/- 0.2) mg/kg XH resulted in mean (+/- SE) induction time of 5.6 (+/- 0.3) min and mean (+/- SE) first reaction time of 59.3 (+/- 6.5) min. Convulsions occurred four times (9%), but with no noteworthy consequences.

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A combination of xylazine hydrochloride-ketamine hydrochloride was used to immobilize 83 wild red foxes (Vulpes vulpes) (15 pups and 68 adults) at Doñana National Park (Spain). Mean ketamine hydrochloride doses were 17.1 mg/kg (SE = 1.53) and 12.3 mg/kg (SE = 0.4) for pups and adults, respectively, and mean xylazine hydrochloride doses for the same groups were 6.2 mg/kg (SE = 0.63) and 4.7 mg/kg (SE = 0.14), respectively. Mean induction times and first reaction times were 1.6 minutes and 22.5 minutes for pups and 3.8 minutes and 39.4 minutes for adults, respectively. Recommended doses for wild adult foxes of unknown weight are 75 mg of ketamine hydrochloride and 20 mg of xylazine hydrochloride.

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