Sexual differences in at-sea behaviour of seabirds often derive from size dimorphism and may lead to both resource partitioning and diverging threats between the sexes. Spheniscids are among the least dimorphic of the seabird families and are the most threatened. In many instances, diet differs between the sexes in penguins, but few studies have compared their foraging behaviour, partly because of the difficulty of identifying sexes in the field. We derived a discriminant function analysis that predicts the sex of African penguins Spheniscus demersus with > 90% confidence, using only beak length and depth. We also deployed GPS-time-depth recorders on male and female penguins breeding on 2 of their largest colonies in South Africa over 2 consecutive breeding seasons and compared their at-sea behaviour. Foraging effort (time spent at sea, distance covered) showed greater variance with clutch mass and between years and colonies than between sexes. However, although maximum diving capabilities were similar, males dived deeper and longer on average than females. Females compensated by increasing their diving frequency, which resulted in similar volumes of water being explored, and foraged over larger foraging areas. There was also some spatial separation between sexes, although foraging range overlap differed markedly (35 to 83%) between years and islands, presumably reflecting prey availability and the need to minimise between-sex competition. The results suggest potential niche partitioning between the sexes in African penguins, but could also be a passive consequence of sexual dimorphism driven primarily by sexual selection. Female behaviour may make them more at risk from predation or oiling events, highlighting the possibility of sex-dependent vulnerability in this Endangered species.

The Kruger National Park is a stronghold for African wild dog Lycaon pictus and cheetah Acinonyx jubatus conservation in South Africa. Tourist photographic surveys have been used to evaluate the minimum number of wild dogs and cheetahs alive over the last two decades. Photographic-based capture-recapture techniques for open populations were used on data collected during a survey done in 2008/9. Models were run for the park as a whole and per region (northern, central, southern). A total of 412 (329–495; SE 41.95) cheetahs and 151 (144–157; SE 3.21) wild dogs occur in the Kruger National Park. Cheetah capture probabilities were affected by time (number of entries) and sex, whereas wild dog capture probabilities were affected by the region of the park. When plotting the number of new individuals identified against the number of entries received, the addition of new wild dogs to the survey reached an asymptote at 210 entries, but cheetahs did not reach an asymptote. The cheetah population of Kruger appears to be acceptable, while the wild dog population size and density are of concern. The effectiveness of tourist-based surveys for estimating population sizes through capture-recapture analyses is shown.

The impacts of high ambient temperatures on mortality in humans and domestic animals are well‐understood. However much less is known about how hot weather affects mortality in wild animals. High ambient temperatures have been associated with African wild dog Lycaon pictus pup mortality, suggesting that high temperatures might also be linked to high adult mortality. We analyzed mortality patterns in African wild dogs radio‐collared in Kenya (0°N), Botswana (20°S), and Zimbabwe (20°S), to examine whether ambient temperature was associated with adult mortality. We found that high ambient temperatures were associated with increased adult wild dog mortality at the Kenya site, and there was some evidence for temperature associations with mortality at the Botswana and Zimbabwe sites. At the Kenya study site, which had the highest human impact, high ambient temperatures were associated with increased risks of wild dogs being killed by people, and by domestic dog diseases. In contrast, temperature was not associated with the risk of snare‐related mortality at the Zimbabwe site, which had the second‐highest human impact. Causes of death varied markedly between sites. Pack size was positively associated with survival at all three sites. These findings suggest that while climate change may not lead to new causes of mortality, rising temperatures may exacerbate existing anthropogenic threats to this endangered species, with implications for conservation. This evidence suggests that temperature‐related mortality, including interactions between temperature and other anthropogenic threats, should be investigated in a greater number of species to understand and mitigate likely impacts of climate change. ​

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