Giraffes (Giraffa camelopardalis peralta) of Niger
Thirty years ago giraffes were found all over the Sudano-Sahelian area, from Mauritania to Chad. Over the last 20 years, due to loss of habitat and poaching, giraffe populations have decreased. In Niger large herds were present in the Tanout area, between Agadez and Zinder, but they disappeared because of recurring drought. During the eighties, […]
Population Status and Trend of the Maasai Giraffe in the Mid Kenya-Tanzania Borderland
Among the nine sub-species of giraffes, the Maasai giraffe is the most widespread and common in Northern and Southern Kenya. Although it’s considered by the IUCN to be a species of no conservation concern, they have been reported to have declined in some of their range areas mostly due to bush meat activities, habitat fragmentation […]
Vegetation factors influencing density and distribution of wild large herbivores in a southern African savannah
Understanding factors influencing large herbivore densities and distribution in terrestrial ecosystems is a fundamental goal of ecology. This study examined environmental factors influencing the density and distribution of wild large herbivores in Gonarezhou National Park, Zimbabwe. Vegetation and surface water were predicted to have a stronger influence than anthropogenic-related disturbances (livestock grazing, fires, settlements and […]
Comparative changes in adult vs. juvenile survival affecting population trends of African ungulates
Among large mammalian herbivores, juvenile survival tends to vary widely and may thus have a greater influence on population dynamics than the relatively constant survival rates typical of adults. However, previous studies yielding stage-specific survival rates have been mostly on temperate zone ungulates and in environments lacking large predators. Annual censuses coupled with assessments of […]
Oscillations in large mammal populations: are they related to predation or rainfall?
Cyclic population dynamics is relatively common among populations of small mammals in high latitudes but is not yet established among African savanna ungulates. However, oscillations may be expected in large mammal populations subject to quasi-periodic oscillations in regional rainfall. We evaluated evidence for environmentally entrained oscillations in a large-mammal predator–prey system in Kruger National Park […]
Trends in populations of elephant and other large herbivores in Gonarezhou National Park, Zimbabwe, as revealed by sample aerial surveys
For 30 years, regular aerial surveys in Zimbabwean protected areas were funded, designed and executed primarily to estimate elephant numbers. Other large herbivores were recorded, even though some species were not easily seen from the air in savannah woodlands. Population estimates for species other than elephant provided indices of abundance that could be used to […]
Shifts in native ungulate communities on a former cattle ranch in Tanzania
When an area is brought under protection, current animal populations and their habitat preferences need to be assessed to predict population trends and future habitat availability. Using data from walking transects, we estimated the size of native ungulate populations on an abandoned cattle ranch in a coastal savannah in Tanzania, now included in the new […]
Has the final countdown to wildlife extinction in Northern Central African Republic begun?
The wildlife populations of Northern Central African Republic experienced precipitous declines during the 1970s and 1980s. While anecdotes coming out of the region indicate that the wildlife populations remain under serious threat, little is known about their status. An aerial sample count was carried out in the Northern Central African Republic at the end of […]
Herbivore Dynamics and Range Contraction in Kajiado County Kenya: Climate and Land Use Changes, Population Pressures, Governance, Policy and Human-wildlife Conflicts
Wildlife populations are declining severely in many protected areas and unprotected pastoral areas of Africa. Rapid large-scale land use changes, poaching, climate change, rising population pressures, governance, policy, economic and socio-cultural transformations and competition with livestock all contribute to the declines in abundance. Here we analyze the population dynamics of 15 wildlife and four livestock […]
Conservation monitoring: estimating mammal densities in woodland habitats
Conservation and ecological monitoring programmes often estimate animal densities over time, but in wooded and forested areas practical techniques are still poorly developed. Here I have examined five simple methods of deriving densities of large and medium-sized mammals using line transects driven through miombo woodland habitat in Africa. These methods calculated area by dividing the […]