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The southern Norwegian wolverine (Gulo gulo) population was considered functionally extinct in the 1960s but has partly recovered in recent years. Proper management of this population is highly dependent on reliable estimates of critical population parameters such as population size, sex ratio, immigration rate, and reproductive contribution from immigrants. We report on a large-scale population monitoring project assessing these parameters through genetic tagging of individuals, with feces as the source of DNA. Sixty-eight different individuals were detected among 147 successfully genotyped samples collected in 2000 and 2001. Sixty of these individuals were represented in the 2001 sample, which may be considered a minimum estimate of the population size. Almost 50% of these animals were sampled only once, however, indicating that the true population size may be markedly higher. Accordingly, a capture-recapture estimate based on the observed resampling rates suggested a population size of 89 wolverines (95% confidence interval (CI) = 74-104), which is approximately 35% higher than an estimate of 64 obtained from the number of active natal dens (95% CI = 46-95; p = 0.08). Indirect estimates of dispersal distances inferred from mother-offspring relationships sug- gested that wolverine males have the ability to disperse up to 500 km, a distance exceeding anything previously reported in the literature. Dispersal distances of more than 100 km were detected for females. Bayesian clus- tering analysis and subsequent assessment of individual relationships suggest that immigrants from northern Scandinavia have contributed and still contribute to the southern Norwegian gene pool, counteracting genetic erosion and reducing the risk of inbreeding depression. Additional sampling efforts will be undertaken during the coming years to allow for observations of population trends, immigration rate, and reproductive variance among individuals. Such data will provide an important basis for the design of an appropriate conservation plan for this small and vulnerable population.

Swayne's hartebeest (Alcelaphus buselaphus swaynei) is an endangered antelope that survives in four or five relict populations in Ethiopia. We examined the two main populations (Senkele and Nechisar) for mitochondrial (D-loop) and nuclear (microsatellite) variability in order to measure levels of genetic variation within the subspecies and degree of differentiation between populations. For comparison, we examined samples from a large population of red hartebeest (Alcelaphus buselaphus caama). Both swaynei and caama exhibited high levels of variation. There was significant differentiation between the populations of swaynei at Senkele and Nechisar, and gene diversity in Nechisar, the smaller of the two populations, was significantly lower than that in Senkele. Many mitochondrial haplotypes and microsatellite alleles present at high frequencies among the Senkele individuals were missing in Nechisar, suggesting that the translocation of animals from Senkele undertaken in 1974 did not contribute notably to the gene pool in Nechisar. Subsamples taken from Senkele in 1988 and 1995 showed a significant change in allele frequencies, a change that probably can be attributed to a massive population decline during this period. We recommend that both populations be protected in situ to maintain as much as possible of the diversity that exists within the taxon and that a breeding program be established. In spite of the earlier unsuccessful attempt, we argue that translocation of animals for enhancement of population size as well as genetic variation in Nechisar should be considered. Resumen: El alcelafo de Swayne (Alcelaphus buselaphus swaynei) es un antilope en peligro que sobrevive en cuatro o cinco poblaciones relicto en Etiopia. Examinamos la variabilidad mitocondrial (curva-D) y nuclear (microsatelite) en las dos principales poblaciones (Senkele y Nechisar) para medirlos niveles de variabilidad genetica en las subespecies y el nivel de diferenciacion entre poblaciones. Para comparacion, se examinaron muestras de una poblacion grande de alcelafo rojo (Alcelaphus buselaphus caama). Tanto swaynei como caama presentaron altos niveles de variacion. Hubo diferencia significativa entre las poblaciones de swaynei en Senkele y Nechisar, y la diversidad genica en Nechisar, la poblacion mas pequena, fue significativamente menor que la de Senkele. Muchos haplotipos mitocondriales y alelos microsatelitales presentes en frecuencias altas en Senkeles estuvieron ausentes en Nechisar, lo que sugiere que la translocacion de animales de Senkele en 1974 no contribuyo notablemente a la poza genica de Nechisar. Submuestras tomadas de Senkele en 1988 y 1995 mostraron un cambio significativo en la frecuencia de alelos, cambio que se puede atribuir a la declinacion poblacional masiva durante ese periodo. Recomendamos que las poblaciones se protejan in situ para mantener la mayor diversidad posible dentro del taxon y que se establezca un programa de reproduccion. A pesar del infructuoso intento anterior, se debe considerar la translocacion de animales para incrementar el tamano poblacional y la variabilidad genetica en Nechisar.