How Immunocontraception Can Contribute to Elephant Management in Small, Enclosed Reserves: Munyawana Population as a Case Study

Immunocontraception has been widely used as a management tool to reduce population growth in captive as well as wild populations of various fauna. We model the use of an individual-based rotational immunocontraception plan on a wild elephant, Loxodonta africana, population and quantify the social and reproductive advantages of this method of implementation using adaptive management. The use of immunocontraception on an individual, rotational basis stretches the inter-calving interval for each individual female elephant to a management-determined interval, preventing exposing females to unlimited long-term immunocontraception use (which may have as yet undocumented negative effects). Such rotational immunocontraception can effectively lower population growth rates, age the population, and alter the age structure. Furthermore, such structured intervention can simulate natural process such as predation or episodic catastrophic events (e.g., drought), which regulates calf recruitment within an abnormally structured population. A rotational immunocontraception plan is a feasible and useful elephant population management tool, especially in a small, enclosed conservation area. Such approaches should be considered for other long-lived, social species in enclosed areas where the long-term consequences of consistent contraception may be unknown

Genetic sexing of stock-raiding leopards: not only males to blame

Lethal control of stock-raiding predators is generally assumed to have fewer consequences for the species’ population dynamics if it involves males only. However, very little data are available that assess whether shot ‘‘problem’’ animals indeed are essentially males. In this study, we used two independent genetic methods (four X-chromosomal polymorphic microsatellite loci and the sex-specific ZFXY marker) validated against known-sex samples to determine, from skin samples collected over a 6-year period, the sex of 59 leopards (Panthera pardus) shot by farmers in Botswana. We found that out of 53 leopards that could be sexed genetically, 21 were females (39.6 %); males were thus not significantly more often shot than females. Comparing the genetically determined sex of shot leopards to that reported by farmers showed that 58.3 % were mistaken for the opposite sex. Our genetic study revealed that more females than presumed are hunted in response to alleged livestock predation. With females frequently misidentified as males, the current practice of shooting ‘‘problem’’ animals is likely to negatively affect the population dynamics of leopards. These genetic data may be used to guide the development of a revised management policy for large-carnivore hunting. Importantly, models of sustainable harvest need to include female offtake as a parameter

Reproductive success of female leopards Panthera pardus: The importance of top-down processes

Long-term studies on large felids are rare and yet they yield data essential to understanding the behaviour of species and the factors that facilitate their conservation. We used the most extensive data set so far compiled on leopards Panthera pardus to establish baseline reproductive parameters for females and to determine the demographic and environmental factors that affect their lifetime reproductive success. We used comprehensive sightings reports and photographs from ecotourism lodges in the Sabi Sand Game Reserve, South Africa, to reconstruct life histories for 44 female leopards that gave birth to 172 litters over a 32-year period. Leopards appeared to exhibit a birth pulse; most litters were born in the wet season, particularly in December. Mean age at first parturition (n=26, mean±standard error=46±2 months, range=33-62) was older than previously recorded, possibly due to elevated intraspecific competition. Average litter size was 1.9±0.1 (n=140, range=1-3) and declined with maternal age. Age of litters at independence (n=52, 19±1 months, range=9-31) was inversely related to prey abundance but did not affect the likelihood of recruitment of offspring. Interbirth intervals differed following successful litters (in which at least one cub survived to independence; n=55, 25±1 months, range=14-39) and unsuccessful litters (n=46, 11±1 months, range=4-36), as did the time taken to replace litters. Variation in lifetime reproductive success was influenced mainly by differences in cub survival, which was related to maternal age and vulnerability to infanticide. Cub survival (37%) declined as females got older, perhaps because mothers relinquished portions of their home ranges to philopatric daughters. Male leopards were responsible for many (40%) cub deaths and females appeared to adopt severalstrategies to counter the risk of infanticide, including paternity confusion and displaying a period of reduced fertility immediately after a resident male was replaced. Our results suggest that the reproductive success of female leopards is regulated primarily by top-down processes. This should be taken into account in management decisions, particularly when managers are considering the implementation of invasive activities such as legal trophy hunting. © 2012 The Authors. Mammal Review © 2012 John Wiley and Sons Ltd and The Mammal Society