Detecting early warnings of pressure on an African lion (Panthera leo) population in the Queen Elizabeth Conservation Area, Uganda

Abstract

1. African lions are declining across much of their range, yet robust measures of population densities remain rare. The Queen Elizabeth Conservation Area (QECA; 2,400 km 2 ) in East Africa's Albertine Rift has potential to support a significant lion population. However, QECA lions are threatened, and information on the status of lions in the region is lacking.2. Here, we use a spatially explicit search encounter approach to estimate key population parameters of lions in the QECA. We then compare home range sizes estimated from our models to those from a radio-collaring study implemented a decade earlier.3. We recorded 8,243.5 km of search effort over 93 days, detecting 30 individual lions (16 female and 14 male) on 165 occasions at a rate of 2 lion detections/100 km 2 .Lion density in the QECA was 2.70 adult lions/100 km 2 (SD = 0.47), while mean abundance was 71 individuals (SD = 11.05).4. Worryingly, the movement parameter for male lions was 3.27 km and 2.22 km for females, suggesting > 400%, and > 100% increases in home range size, respectively, compared to a decade earlier. Sex ratio of lions in the QECA was lower (1 male: 0.75 females), when compared to a previously published review (mean = 1:2.33).

Evidence for increasing human‐wildlife conflict despite a financial compensation scheme on the edge of a Ugandan National Park

“…Many Ugandans have a very strong cultural and economic connection to cattle production, and with an average of 50 cows/km 2 (Cook, 2015) the country has the highest density of cattle anywhere on the continent, and the eighth highest in the world (Robinson et al, 2014). Large carnivores regularly raid cattle and other livestock (Ochieng, Ahebwa, & Visseren‐Hamakers, 2015) and are killed in retaliation through poisoning, trapping or shooting (Braczkowski et al, 2020; Tweheyo, Tumusiime, Turyahabwe, Asiimwe, & Orikiriza, 2012). Examples of this conflict include at least 19 African leopards (hereafter leopards) being killed on the boundary of the Lake Mburo National Park in a 4‐year period from 2003 to 2006 (CITES 2014), and at least 47 adult and sub‐adult lions being killed between 2006–2012 in the Queen Elizabeth Conservation Area (Braczkowski et al, 2020).…”

Population estimates of large carnivores and their conflict with humans in East Africa and India

“…The high density of hyenas, lend some support to our a priori hypothesis that they may have experienced a degree of competitive release, resultant of a decrease in lion density in the QECA (this decrease over a ten-year period is described in Braczkowski et al 2020). Creel and Creel (1996) found spotted hyenas to outnumber lions in some of Africa's largest and most pristine protected area systems (Selous, Kruger, Ngorongoro and Serengeti) on average by a ratio of 1 hyena: 0.33 lions (range=1:0.17-1:0.75).…”

“…This baseline could be of use to managers and conservation stakeholders in any future recovery efforts, however because we had only a single snapshot in time, it was impossible for us to assess whether the leopard population in the QECA is stable, decreasing or increasing. Braczkowski et al (2020) found African lion movements in the QECA had increased dramatically in the region over a ten-year period, and the proportion of females to males was low. Similarly, our leopard surveys detected a low ratio of adult female leopards in both regions of the QECA, particularly the south.…”

“…The threats of human-carnivore conflict, poaching of preferred prey and habitat loss, call for the effective monitoring of carnivore populations, not only in setting baselines of population density where they are lacking, but also for future targets. In regions where significant declines have already occurred, robust monitoring can provide a current snapshot for recovery planning (Braczkowski et al 2020). Indeed, the field of wildlife population monitoring represents one of the most central topics in conservation biology.…”

“…It is likely that the extinction risk of large carnivores in Uganda is high because of the above factors (UWA 2010). Lions (Panthera leo), for example, have already been extirpated from 50% of Uganda's national parks and reserves (UWA 2010) and occur at depressed densities, even in its largest, transfrontier parks (Braczkowski et al 2020).…”