Cannibalism is a common phenomenon among young wolf spiders (Lycosidae). The purpose of this study was to investigate how various factors influence cannibalistic tendencies in hatchlings of Pardosa amentata (Clerk 1757). The basic experimental approach was to place pairs of unfed hatchlings of similar body mass in small containers without prey and to measure if and when cannibalism happened. From the data, we identified three different cannibalistic strategies. One large group of hatchlings never cannibalized and thus died from starvation. Another group cannibalized shortly before the time at which they were predicted to die from starvation. In these spiders, there was a strong positive relationship between average body mass of the contestants and their latency to cannibalize. A third group cannibalized quickly and the latency to cannibalize in these spiders was independent of body mass. We also tested if cannibalistic tendencies were higher among unrelated pairs than among pairs of siblings, but we did not find any support for this hypothesis. In another experiment we tested if maternal effects influenced cannibalism, i.e. if siblings from certain mothers were more cannibalistic than siblings from others. We did not find any evidence that maternal effects influenced whether or not cannibalism occurred. However, when cannibalism did occur, the latency to cannibalize varied significantly among siblings from different mothers beyond what would have been predicted solely from hatchling body mass.

During the last century, many species have become endangered and conservation in terms of captive breeding has been crucial for their survival. Classical management of captive species is based on recorded genealogies. However, if pedigrees are incomplete or inaccurate, it can bias the interpretation of the results obtained from analyses based on such data. In this investigation, 12 microsatellite loci were investigated to evaluate the studbook information of the critically endangered Persian wild ass, Equus hemionus onager. Relatedness and inbreeding coefficients were calculated in order to compare the same coefficients estimated from the recorded studbook. A significant correlation between coefficients obtained by microsatellites and the studbook validates the recorded studbook as a reasonable tool for future genetic management. Furthermore, a Bayesian-based method divided the captive onager population into four subgroups that indicate departure from random mating, and thus minor rotation of animals between zoos. Lastly, analyses for inferring past demographic changes revealed a gradual population decline and inbreeding over several generations. This may indicate a low genetic load in captive onagers as a consequence of some degree of purging. Consequently, the risk of inbreeding depression should currently be minimal in the captive breeding program. Therefore, it is recommended to increase the connectivity between the four subgroups of onagers in order to reduce the risk of demographic and genetic stochasticity. This study underlines the importance of using molecular markers to evaluate genetic management of captive breeding programs.

Although the European population of Asiatic lions (Panthera leo persica) has been managed under the European Endangered Species Program (EEP) since 1990, little is known about the health status of the population. This study was designed to characterize mortality for this population through examination of the studbook and other records on 392 Asiatic lions living in the EEP between 2000 and 2014. A total of 270 animals died during the period with 80% of them being under 1 year old. The mortality rate for under 1 year olds was 54%, while the odds of survival of cubs within a litter increased if the dam had had litters previously. Survival to reproductive age was 44%. Post-mortem reports were requested and the cause of death was obtained for 133 animals. Trauma inflicted by a conspecific and lack of care were common causes of death (26% and 22%, respectively) and were also responsible for most of the neonatal mortalities. Congenital defects were responsible for 9% of deaths, although the true prevalence is likely underestimated. A common necropsy protocol for all Asiatic lion collections is needed to facilitate future studies. Zoo Biol. 36:66-73, 2017. © 2017 Wiley Periodicals, Inc.

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