Rapid Growth Rates of Lion (Panthera leo) Populations in Small, Fenced Reserves in South Africa: A Management Dilemma

Abstract

Managers of reintroduced lion (Panthera leo) populations in small reserves (<1000 km2 ) in South Africa are challenged by high rates of population increase and how best to control them. We combined data from 14 small, fenced reserves to evaluate growth rate parameters and compared them to those in larger and/or open reserves. Growth rates of lions in small fenced reserves were only matched by those in Nairobi National Park (NP), which is relatively small and where the majority of the subadults emigrated away from the park. Initially, South African managers unconsciously mimicked this system by removing subadults to control population numbers, but increasingly chose euthanasia and hunting in the past decade, as the demand for wild lions for translocation decreased. They have, however, expressed a desire to use other methods of population control and mimic other open systems such as Kruger NP and Serengeti NP. Kruger NP had older ages of first reproduction and longer inter-birth intervals that could be mimicked through selective contraception. Alternatively, Serengeti NP had smaller litter sizes and lower cub survival, which could be mimicked through surgery to reduce litter sizes and, less attractively as it still involves lethal management and raises serious ethical concerns, selective culling of cubs. Mimicking Kruger NP may be more desirable as it is more ecologically similar to the small reserves than Serengeti NP. This understanding of the current situation, and how it could be altered to more closely mimic natural systems, will facilitate the development of a metapopulation-based management plan for lions in small reserves in South Africa.

Ambient temperature provides an adaptive explanation for seasonal reproduction in a tropical mammal

“…African wild dogs’ reproductive seasonality contrasts with patterns in other large African carnivores such as leopards ( Panthera pardus ), lions ( Panthera leo ), cheetahs ( Acinonyx jubatus ) and spotted hyaenas ( Crocuta crocuta ), which reproduce year‐round even at Africa's highest latitudes (Balme et al ., ; Miller & Funston, ; Crosier et al ., ; Terio et al ., ; Lindeque & Skinner, ). In some populations of these species, births are skewed to certain times of year (Holekamp et al ., ; Balme et al ., ; Rudnai, ), but nevertheless births occur in all months and reproductive seasonality is much less extreme than that described here.…”

Niche overlap and dietary resource partitioning in an African large carnivore guild

“…Mills & Gorman, ; Jenkins et al , but see Hayward et al , ). This is potentially further exacerbated, as reintroduced large predators frequently breed, increasing their population size and rapidly exceeding their site‐specific sustainable densities (Miller & Funston, ). The density of competitively superior carnivores, such as lion Panthera leo, may be artificially high on these small protected areas (Creel et al , ), potentially altering the behaviour of competitively subordinate meso‐predators (Bissett et al , ).…”

Early post-release movement of reintroduced lions (Panthera leo) in Dinokeng Game Reserve, Gauteng, South Africa

“…In South Africa, there has been an increase in establishment of small reserves and demand for reintroducing flagship carnivores including lions, leopards (Panthera pardus), cheetahs (Acinonyx jubatus), wild dogs (Lycaon pictus) and spotted hyaenas (Crocuta crocuta) in recent years (Hayward et al 2007a, b). Most studies on reintroduced carnivores have focused mainly on population control, inbreeding, diseases and human-wildlife conflicts (Ferreira and Hofmeyr 2013;Miller and Funston 2014), while information on post-release movement behaviour is limited (Hayward et al 2007b;Hunter et al 2007). Post-release movement pattern allows us to understand the exploration-exploitation trade-off of reintroduced animals during establishment stage and individual variation in movement strategies in adapting to a new environment, which can be used as a tool to assess establishment success (Berger-tal and Saltz 2014).…”