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1.
We studied the seasonal home ranges and space use of three breeding herds of elephants (Loxodonta africana) for 3–5 years in an area comprising South Africa’s Sabi Sand Reserve (SSR) and Kruger National Park (KNP). Global Positioning System (GPS) transmitters were attached to the matriarchs of three herds and set to transmit a single daily location. Each herd was located in SSR 31%, 60% and 84% of the time. During the wet summer months, the herds walked longer distances and occupied larger seasonal home ranges than during the corresponding dry winter period. Core areas were centred on riverine habitats within both parks, with all three herds exhibiting closer distances to rivers and artificial water holes than would be expected if they were moving randomly. Home ranges within SSR overlapped much of the park. However, in KNP they occupied discrete areas with little overlap. Much of the movement between the two parks occurred along well‐defined corridors. This study shows that elephant herds depended upon the resources of both parks, providing an insight into their within‐ and between‐seasonal movements. This highlights the importance of ongoing co‐operation between wildlife managers from both parks when forming policy.  相似文献   

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  • 1.1. Blood, liver, heart, testis, skin, eye, muscle and kidney samples were obtained from elephants (Loxodonta africana) in the Kruger National Park during a culling programme in April 1992.
  • 2.2. Gene products of 25 protein coding loci in L. africana were examined by horizontal starch-gel electrophoresis.
  • 3.3. Eighteen protein coding loci (72%) displayed monomorphic gel banding patterns whereas only seven (28%) displayed polymorphic gel banding patterns.
  • 4.4. Average heterozygosity values for adults, youngsters and the total population are respectively 0.058, 0.024 and 0.047.
  • 5.5. Relative gene diversities within and between populations are 84% and 16% respectively.
  • 6.6. Two population simulation programmes were utilized to predict the duration of the current variability present in this species, based on current genetic variation and gene transfer from one generation to the next.
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This is the first study where elephant footprints as habitat for aquatic macroinvertebrate communities were assessed. Preliminary observations during the dry season in Kibale Forest, Uganda, indicated that water‐filled footprints constituted the majority of stagnant ponds. Consequently, this study aimed at giving an overview of the diversity and ecology of those habitats and the capacity of elephants as ecosystem engineers. The fauna and abiotic factors (age, size, substrate, organic matter, pH, canopy cover, temperature, conductivity) of 30 water‐filled natural elephant footprints were sampled, resulting in the record of 61 morphospecies among 27 families/orders. Species composition was dominated by Hydrophilidae and Dytiscidae and influenced by environmental variables, such as age and organic matter. To study the colonization process, 18 artificial footprints were created within different distances from the water source. After 5 days, 410 specimens were collected, with higher species richness in artificial footprints closer to a natural water source. We conclude that colonization of water‐filled footprints is fast, they constitute important habitats with high diversity and variability, and they act as stepping stones for dispersal and add to the ability of elephants as ecosystem engineers. We emphasize the importance of elephants as a key species in ecosystem dynamics and conservation practice.  相似文献   

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Most African elephant (Loxodonta africana africana) populations are isolated and thus threatened by a loss of genetic diversity. As a consequence, genetic analysis of African elephant populations will play an increasing role in their conservation, and microsatellite loci will be an important tool in these analyses. Previously published sets of polymorphic microsatellites developed for African elephants are all dinucleotide repeats, which are prone to typing error. Here, we characterize 11 tetranucleotide microsatellite loci in the African elephant. All loci were polymorphic in 32 faecal samples and two tissue samples from 33 individual African savannah elephants.  相似文献   

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To avoid unnecessary waste of limited resources and to help prioritize areas for conservation efforts, this study aimed to provide information on habitat use by elephants between the wet and dry seasons in the Mole National Park (MNP) of Ghana. We compiled coordinates of 516 locations of elephants’ encounters, 256 for dry season and 260 for wet season. Using nine predictor variables, we modeled the probability of elephant's distribution in MNP. We threshold the models to “suitable” and “nonsuitable” regions of habitat use using the equal training sensitivity and specificity values of 0.177 and 0.181 for the dry and wet seasons, respectively. Accuracy assessment of our models revealed a sensitivity score of 0.909 and 0.974, and a specificity of 0.579 and 0.753 for the dry and wet seasons, respectively. A TSS of 0.488 was also recorded for the dry season and 0.727 for the wet season indicating a good model agreement. Our model predicts habitat use to be confined to the southern portion of MNP due to elevation difference and a relatively steep slope that separates the northern regions of the park from the south. Regions of habitat use for the wet season were 856 km2 and reduced significantly to 547.68 km2 in the dry season. We observed significant overlap (327.24 km2) in habitat use regions between the wet and dry seasons (Schoener's D = 0.922 and Hellinger's‐based I = 0.991). DEM, proximity to waterholes, and saltlicks were identified as the key variables that contributed to the prediction. We recommend construction of temporal camps in regions of habitat use that are far from the headquarters area for effective management of elephants. Also, an increase in water point's density around the headquarters areas and selected dry areas of the park will further decrease elephant's range and hence a relatively less resource use in monitoring and patrols.  相似文献   

7.
A series of aerial counts of elephant made between 1968 and 1972 in the Rwenzori National Park and Chambura Game Reserve, Uganda, is described. A summary is included of all previous aerial counts made in the region. Numbers present in the park since 1963 averaged 1752 during the dry seasons, some 3/5 of the wet season mean of 2896. Corresponding figures for the reserve are 325 and 501. The distribution was very significantly aggregated for each count and remained so when the totals for all counts were lumped. The distribution tended to be more aggregated in dry than in wet seasons. The overall density in the park was 1.43 elephant km-2 with wet and dry season means of 1.74 and 1.05 respectively. Corresponding figures for the reserve are 2.06, 2.42 and 1.57 km-2. The mean group size in the park was 6.3 elephant but there were significant variations over the whole range of observations although not between wet and dry season means. The elephant in the reserve were highly aggregated with a mean group size of 28.8. It is concluded that there was a significant rise in the wet season population of the park between 1963 and 1968 but that subsequently, numbers remained fairly stable. Numbers in the dry season and in the reserve at all seasons have not varied significantly since 1963. It is suggested that the wet season rise has been due to a reduction in the area of grazing land available outside the park at this time of year. It is concluded that vegetational differences are responsible for the un even distribution of elephant with human disturbance having an effect in some areas. It is believed that in the region censused, there are at least three distinct populations of elephant of which only that in the reserve is showing signs of stress.  相似文献   

8.
There has been considerable uncertainty about the abundance estimation of Loxodonta africana within tropical lowland moist forests in Zaire. We surveyed a 15,570 km2 area within the forests of eastern Zaire using transect sampling methods and estimated the elephant population to be 3720 (range 2300–5000) individuals. Dung pile densities were significantly different between adjacent settlement, deep forest, and deep forest core strata, with the most remote area harbouring the highest density. Evidence of elephant poaching was encountered throughout the survey area suggesting that elephant populations continue to be at severe risk.  相似文献   

9.
Negative influences on the establishment and persistence of large trees used by tree‐nesting birds as nesting sites represent a potential threat to vultures and raptors. We monitored large trees and their surrounding vegetation and analysed whether trees with nesting sites are at risk due to elephant impact. Trees with nests did not differ in elephant impact from control trees without nests, and the survival rates of trees with nests and the actual nests within the trees showed that nests decreased at a faster rate than the trees themselves. Elephant damage did not affect the persistence of nests over the 5‐year monitoring period. However, the presence of insects and fungus on large trees was negatively related to tree survival, thereby indicating that elephant impact could indirectly facilitate insect and fungus attack and shorten the lifespan of a tree.  相似文献   

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The substantial increase in elephant populations across many areas in southern Africa over past decades is prompting concerns about the effects on biodiversity. We investigated the outcomes of elephant disturbance on tree-species presence, density, and richness, and on alpha and beta diversity within riparian woodland in Chobe National Park, Botswana. We enumerated all tree species occurring in 32 plots (0.06 ha) along the Chobe riverfront. Plots were stratified by soil type (nutrient-rich alluvium vs. nutrient-poor Kalahari sand covering alluvium) and elephant impact (high vs. low impact on both soil types). We tested four predictions: elephants reduce tree density, richness, and alpha diversity; beta diversity is greater in vegetation subjected to high elephant impact; elephant impact on tree-species composition is greater on nutrient-poor than on nutrient-rich soil; and the loss or decline of abundant tree species on heavily disturbed sites is offset by an increase in abundance of functionally similar species, ones that are minor on lightly disturbed sites. Elephant browsing substantially affected tree-species composition, reducing density, species richness, evenness, and alpha diversity but had no effect on beta diversity. The dominant species on relatively undisturbed areas were partly replaced by functionally similar species on heavily disturbed sites. Soil type influenced species composition on lightly disturbed sites but was less important at higher elephant densities. Our findings are important for areas with extreme dry-season densities of elephants but should not be extrapolated to infer purported effects of elephants on tree diversity at lower densities.  相似文献   

15.
Crop raiding by the elephants is a serious and recurring management problem around protected areas in Kenya such as Meru National Park. Crop-raiding menace is one of the most significant of human–elephant conflicts in Meru National Park. The distribution, impact, and conservation implications of the increased elephant crop raiding in areas adjacent to Meru National Park is attributed to the changes in land use systems within these areas. Crop raiding by African elephants (Loxodonta africana) was monitored in the area adjacent to Meru National Park between August 2010 and July 2011. From the study, 144 farms were raided and farmers lost crops amounting to USD 120,308.60. Crop raiding was higher during the month of August 2010 (KES 2,714,295 or USD 33,928). The study suggests capacity building for communities in order to safeguard their crops against elephant raiding. Other probable measures put forward to mitigate this include the development of alternative water sources and the need to implement electric fence around the remaining section of the Park boundary which is affected by elephant.  相似文献   

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Poaching and habitat encroachment for human settlement are the two major factors that caused contraction of elephant populations in Africa. While the effects of poaching on many aspects of elephant social systems have been studied, the impacts on mating patterns are not yet understood and such information is still lacking in most African countries. In this study, we used elephant specific-microsatellite DNA to generate genotypes from 86 elephant samples (84 fresh faeces and two tissue samples) from Tarangire National Park (TNP), Tanzania to assess the mating success of individual males. We also tested whether the oldest bulls are more likely to sire most of the offspring in a severely poached population. Genetic paternity analysis was compared to behavioural observations of matings collected over a 3-year period (1998–2001) to determine the success of bull mating strategy. The genotypes of 26 infants, their known mothers and 10 out of 43 potential breeding bulls in TNP were used to assign 31% of the offspring at 80% confidence level to their potential fathers with simulation assuming that 23% (10/43) of the breeding males were sampled. Mating success of individual bull based on both behavioural and genetic data showed that the oldest remaining bulls performed most of the matings and fathered the majority of infants. We speculate that the lifetime fitness of bulls that have survived poaching may be elevated because their period of dominance increases.  相似文献   

20.
Fifty-five warthogs [Phacochoerus aethiopicus (Suidae: Artiodactyla)] from the Kruger National Park, Republic of South Africa, were examined for parasites. Adult filarial nematodes were found in lymphatic vessels adjacent to peripheral and visceral lymph nodes, and microfilariae were found in lymph nodes and circulating blood. Both the adult parasite and the microfilaria are described. Specific identification is pending confirmation and recovery of intact adult specimens and microfilariae identical to those described herein.  相似文献   

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