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1.
An isolated population of approximately 50 lions (Panthera leo L.) in Waza National Park, Cameroon, caused considerable damage to livestock. Home range sizes of five collared lions were assessed, the mean was very large: 630 km2. The lions differed in their stock raiding behaviour, with two male habitual problem animals, one female nonproblem animal and two female seasonal problem animals that left the Park in the wet season. Together, they were inferred to kill over 100 heads of cattle annually.  相似文献   

2.
The spatial ecology of Africa lions (Panthera leo) was studied from 2007 to 2009 in Waza National Park, Cameroon, by equipping individual lions with GPS/VHF radio-collars. Mean home range estimates using 100% minimum convex polygons (MCP) and 95% kernel-density estimation (KDE) were respectively 1015 km2 and 641 km2. The lions spent a considerable amount of time out of the park during the study period (21%), resulting in significantly larger wet season home ranges than in the hot dry season when they were largely within the park. Time spent outside of the park coincided with increased livestock predation, especially by males. The seasonal variation observed in home range appeared to be mainly due to prey dispersal, flooding and migrating livestock. Mean home range size was observed to have increased by 58.6% within the last decade. This observed increase in home range could possibly be attributed to recent declines in wild prey abundance and also, may be indicative of a trend of general degradation of the park due to intense human pressure. The change observed in lions’ ranging behaviour was remarkable, with lions crossing the highway parallel to the park to the Cameroon-Nigerian borders. Measures to restore the integrity of the park are urgently needed, which could include the construction of a partial fence along the western boundary of the park to prevent lions moving across the parallel highway.  相似文献   

3.
Lion fecal DNA extracts from four individuals each from Yankari Game Reserve and Kainji‐Lake National Park (central northeast and west Nigeria, respectively) were Sanger‐sequenced for the mitochondrial cytochrome b gene. The sequences were aligned against 61 lion reference sequences from other parts of Africa and India. The sequence data were analyzed further for the construction of phylogenetic trees using the maximum‐likelihood approach to depict phylogenetic patterns of distribution among sequences. Our results show that Nigerian lions grouped together with lions from West and Central Africa. At the smaller geographical scale, lions from Kainji‐Lake National Park in western Nigeria grouped with lions from Benin (located west of Nigeria), whereas lions from Yankari Game Reserve in central northeastern Nigeria grouped with the lion populations in Cameroon (located east of Nigeria). The finding that the two remaining lion populations in Nigeria have different phylogenetic origins is an important aspect to consider in future decisions regarding management and conservation of rapidly shrinking lion populations in West Africa.  相似文献   

4.
Lion (Panthera leo) numbers are in serious decline and two of only a handful of evolutionary significant units have already become extinct in the wild. However, there is continued debate about the genetic distinctiveness of different lion populations, a discussion delaying the initiation of conservation actions for endangered populations. Some lions from Ethiopia are phenotypically distinct from other extant lions in that the males possess an extensive dark mane. In this study, we investigated the microsatellite variation over ten loci in 15 lions from Addis Ababa Zoo in Ethiopia. A comparison with six wild lion populations identifies the Addis Ababa lions as being not only phenotypically but also genetically distinct from other lions. In addition, a comparison of the mitochondrial cytochrome b (CytB) gene sequence of these lions to sequences of wild lions of different origins supports the notion of their genetic uniqueness. Our examination of the genetic diversity of this captive lion population shows little effect of inbreeding. Immediate conservation actions, including a captive breeding programme designed to conserve genetic diversity and maintain the lineage, are urgently needed to preserve this unique lion population.  相似文献   

5.
Two of the eight recognized lion subspecies, North African Barbary lion (Panthera leo leo) and South African Cape lion (Panthera leo melanochaita), have become extinct in the wild in the last 150 years. Based on sequences of mitochondrial DNA (mtDNA) control region (HVR1) extracted from museum specimens of four Barbary and one Cape lion, the former was probably a distinct population characterized by an invariable, unique mtDNA haplotype, whilst the latter was likely a part of the extant southern African lion population. Extinction of the Barbary line, which may still be found in “generic” zoo lions, would further erode lion genetic diversity. Therefore, appropriate management of such animals is important for maintaining the overall genetic diversity of the species. The mtDNA haplotype unique to the Barbary lion, in combination with the small size of the HVR1 analyzed (c. 130 bp), makes it possible and cost-effective to identify unlabelled Barbary specimens kept in museums and “generic” captive lions that may carry the Barbary line. An initial study of five samples from the lion collection of the King of Morocco, tested using this method, shows that they are not maternally Barbary.  相似文献   

6.
Urinary volatile constituents of the lion, Panthera leo.   总被引:1,自引:0,他引:1  
The volatile components of urine from lions were investigated using GC-MS headspace techniques. Fifty-five compounds were found in the urine samples. Seven potential species-identifying compounds were found. Male lion scent marks overlapped significantly more in compound composition with other males than they did with female marks. A similar relationship was not found for the females. Males had a significantly higher absolute content of 2-butanone in their urine than females, and females had a significantly higher relative content of acetone than males. Samples from 13/16 individual lions overlapped more within the individual than they did with samples from the other individuals, but only seven significantly so.  相似文献   

7.
The lion Panthera leo is one of the world's most charismatic carnivores and is one of Africa's key predators. Here, we used a large dataset from 357 lions comprehending 1.13 megabases of sequence data and genotypes from 22 microsatellite loci to characterize its recent evolutionary history. Patterns of molecular genetic variation in multiple maternal (mtDNA), paternal (Y-chromosome), and biparental nuclear (nDNA) genetic markers were compared with patterns of sequence and subtype variation of the lion feline immunodeficiency virus (FIV(Ple)), a lentivirus analogous to human immunodeficiency virus (HIV). In spite of the ability of lions to disperse long distances, patterns of lion genetic diversity suggest substantial population subdivision (mtDNA Phi(ST) = 0.92; nDNA F(ST) = 0.18), and reduced gene flow, which, along with large differences in sero-prevalence of six distinct FIV(Ple) subtypes among lion populations, refute the hypothesis that African lions consist of a single panmictic population. Our results suggest that extant lion populations derive from several Pleistocene refugia in East and Southern Africa ( approximately 324,000-169,000 years ago), which expanded during the Late Pleistocene ( approximately 100,000 years ago) into Central and North Africa and into Asia. During the Pleistocene/Holocene transition ( approximately 14,000-7,000 years), another expansion occurred from southern refugia northwards towards East Africa, causing population interbreeding. In particular, lion and FIV(Ple) variation affirms that the large, well-studied lion population occupying the greater Serengeti Ecosystem is derived from three distinct populations that admixed recently.  相似文献   

8.
The Barbary lion became extinct in the wild around 1942. Since the end of the 19th century, a last purebred captive breeding stock existed at the court of Morocco. The rest of these animals became the core exhibition of the new Rabat Zoo after passing through repeated bottlenecks and possibly some introgression events by foreign lions. This study uses mitochondrial DNA sequencing data to clarify the relationship among these lions and their sub-Saharan and Asian relatives. We analysed mitochondrial cytochrome b sequences obtained from a sample from a Barbary lion descended from a young female of the Barbary lion breeding group at the Rabat Zoo and various other members of the genus Panthera. In our cytochrome-b-based phylogenetic tree, the North African Barbary lion, represented by a biopsy sample from the Neuwied Zoo, joins the Asian lion clade, although it is slightly different from its Asian sister group. However, it is clearly distinct from sub-Saharan lions and can be considered as a genetically defined phylogeographic group of its own. Molecular dating of the extant sub-Saharan and Asian lion groups shows that the split between North African Barbary lions and Asian lions must be considerably more recent than 74–203 kilo years ago.  相似文献   

9.
Africa's large predator guild competes for a limited food resource base. To minimize the degree of competition, we hypothesized that the two largest members of this guild and its fiercest competitors, the lion and the spotted hyaena, would partition their activity patterns to avoid interacting. We used 96‐h continuous follows of focal animal(s) to determine when the six radio‐collared lions and eight radio‐collared spotted hyaenas, reintroduced into Addo Elephant National Park in 2003/2004, were active using a binomial measure of activity which was defined as movements >100 m during each hourly period. Contrary to our predictions, lions and hyaenas did not partition their activity times, probably because of their current low population densities. Both species exhibited a crepuscular activity pattern although hyaenas were far less active during daylight. A sub‐adult lioness minimized competitive interactions by becoming diurnal. This is likely to be a common strategy for lions that have been expelled from their natal pride to become nomadic, as it allows them to minimize kleptoparasitic and agonistic interactions from competitively dominant conspecifics and competitors. The increase in testosterone that occurs in males upon reaching sexual maturity, darkens their pelage and causes them to be more directly impacted by the heat, and thereby affords females an opportunity to escape from males during hot temperatures. Similarly, the longer pelage of young hyaenas restricts their activity to the cooler night‐time.  相似文献   

10.
A combination of medetomidine-tiletamine-zolazepam was used to conduct six immobilizations of free-ranging lions (Panthera leo) in Waza National Park, Cameroon, during 1999 and 2000. Drugs were administered by dart injection at 0.07+/-0.01 (mean+/-SD) mg/kg of medetomidine and 1.8+/-0.5 mg/kg of tiletamine-zolazepam. Chemical immobilization was characterized by smooth inductions (14.1+/-6 min), satisfactory analgesia, and muscle relaxation. One animal was treated for bradypnea. No major alterations of physiologic parameters (heart and respiratory rates, rectal temperature) were seen during immobilization in the other lions. Relative arterial oxygen saturation was measured in two animals and revealed mild hypoxemia. The animals received atipamezole at 0.3+/-0.1 mg/kg intramuscularly for reversal of anesthesia. Recoveries were uneventful. All animals were radiocollared, and no mortalities occurred during an 18-mo follow-up period. Use of medetomidine-tiletamine-zolazepam for anesthesia and reversal of anesthesia with atipamezole appear to be useful for reversible immobilization of free-ranging lions.  相似文献   

11.
This survey was conducted in two protected areas in Nigeria to genetically identify individual lions and to determine the genetic variation within and between the populations. We used faecal sample DNA, a non-invasive alternative to the risky and laborious task of taking samples directly from the animals, often preceded by catching and immobilization. Data collection in Yankari Game Reserve (YGR) spanned through a period of five years (2008 –2012), whereas data in Kainji Lake National Park (KLNP) was gathered for a period of three years (2009, 2010 and 2012). We identified a minimum of eight individuals (2 males, 3 females, 3 unknown) from YGR and a minimum of ten individuals (7 males, 3 females) from KLNP. The two populations were found to be genetically distinct as shown by the relatively high fixation index (FST  = 0.17) with each population exhibiting signs of inbreeding (YGR FIS  = 0.49, KLNP FIS  = 0.38). The genetic differentiation between the Yankari and Kainji lions is assumed to result from large spatial geographic distance and physical barriers reducing gene flow between these two remaining wild lion populations in Nigeria. To mitigate the probable inbreeding depression in the lion populations within Nigeria it might be important to transfer lions between parks or reserves or to reintroduce lions from the zoos back to the wild.  相似文献   

12.
The use of long-acting contraceptives as an effective population control mechanism for free-ranging lions was investigated during a three-year study in the Etosha National Park on five lion prides. Lions were immobilized with ketamine hydrochloride and xylazine hydrochloride. Following immobilization, lionesses were weighed, measured and aged, while serum steroid hormone levels were analysed and vaginal smears were obtained. Physical condition and sexual state were assessed. Individuals were used as control animals or given melengestrol acetate (contraceptive) implants, branded and released; the animals were observed for possible changes in behaviour, birth rate and mortality. Ten treated lionesses were recaptured at irregular intervals to reassess weight and steroid hormone levels, while three lionesses had their implants removed to determine if their fertility would return. The contraceptives prevented pregnancy, were reversible when removed and did not alter lion behaviour significantly, except that sexual behaviour was not recorded in treated lionesses.  相似文献   

13.
Conditions experienced during the nonbreeding period have profound long‐term effects on individual fitness and survival. Therefore, knowledge of habitat use during the nonbreeding period can provide insights into processes that regulate populations. At the Falkland Islands, the habitat use of South American sea lions (Otaria flavescens) during the nonbreeding period is of particular interest because the population is yet to recover from a catastrophic decline between the mid‐1930s and 1965, and nonbreeding movements are poorly understood. Here, we assessed the habitat use of adult male (n = 13) and juvenile male (n = 6) South American sea lions at the Falkland Islands using satellite tags and stable isotope analysis of vibrissae. Male South American sea lions behaved like central place foragers. Foraging trips were restricted to the Patagonian Shelf and were typically short in distance and duration (127 ± 66 km and 4.1 ± 2.0 days, respectively). Individual male foraging trips were also typically characterized by a high degree of foraging site fidelity. However, the isotopic niche of adult males was smaller than juvenile males, which suggested that adult males were more consistent in their use of foraging habitats and prey over time. Our findings differ from male South American sea lions in Chile and Argentina, which undertake extended movements during the nonbreeding period. Hence, throughout their breeding range, male South American sea lions have diverse movement patterns during the nonbreeding period that intuitively reflects differences in the predictability or accessibility of preferred prey. Our findings challenge the long‐standing notion that South American sea lions undertake a winter migration away from the Falkland Islands. Therefore, impediments to South American sea lion population recovery likely originate locally and conservation measures at a national level are likely to be effective in addressing the decline and the failure of the population to recover.  相似文献   

14.
The Asiatic lion (Panthera leo persica) is driven to a single habitat in Gir forests in India for its survival. In order to devise adequate conservation and management strategies for this critically endangered species, it is important to characterize its genetic diversity and understand its population structure. Here we report twenty microsatellite loci, in addition to seven reported earlier, from the genome of a pure Asiatic lion. The microsatellite loci described here will provide potentially useful markers for the assessment of genetic variability in the only existing wild population of the Asiatic lions and other big cat species.  相似文献   

15.
To reconstruct the phylogenetic position of the extinct cave lion (Panthera leo spelaea), we sequenced 1 kb of the mitochondrial cytochrome b gene from two Pleistocene cave lion DNA samples (47 and 32 ky B.P.). Phylogenetic analysis shows that the ancient sequences form a clade that is most closely related to the extant lions from Africa and Asia; at the same time, cave lions appear to be highly distinct from their living relatives. Our data show that these cave lion sequences represent lineages that were isolated from lions in Africa and Asia since their dispersal over Europe about 600 ky B.P., as they are not found among our sample of extant populations. The cave lion lineages presented here went extinct without mitochondrial descendants on other continents. The high sequence divergence in the cytochrome b gene between cave and modern lions is notable.  相似文献   

16.
The recent incorporation of molecular methods into analyses of social and mating systems has provided evidence that mating patterns often differ from those predicted by group social organization. Based on field studies and paternity analyses at a limited number of sites, African lions are predicted to exhibit a strict within‐pride mating system. Extra‐group paternity has not been previously reported in African lions; however, observations of extra‐group associations among lions inhabiting Etosha National Park in Namibia suggest deviation from the predicted within‐pride mating pattern. We analysed variation in 14 microsatellite loci in a population of 164 African lions in Etosha National Park. Genetic analysis was coupled with demographic and observational data to examine pride structure, relatedness and extra‐group paternity (EGP). EGP was found to occur in 57% of prides where paternity was analysed (= 7), and the overall rate of EGP in this population was 41% (= 34). Group sex ratio had a significant effect on the occurrence of EGP (< 0.05), indicating that variation in pride‐level social structure may explain intergroup variation in EGP. Prides with a lower male‐to‐female ratio were significantly more likely to experience EGP in this population. The results of this study challenge the current models of African lion mating systems and provide evidence that social structure may not reflect breeding structure in some social mammals.  相似文献   

17.
Improved age estimation of African lions Panthera leo is needed to address a number of pressing conservation issues. Here we present a formula for estimating lion age to within six months of known age based on measuring the extent of pulp closure from X-rays, or Ratio Of tooth AReas (ROAR). Derived from measurements taken from lions aged 3–13 years for which exact ages were known, the formula explains 92% of the total variance. The method of calculating the pulp/tooth area ratio, which has been used extensively in forensic science, is novel in the study of lion aging. As a quantifiable measure, ROAR offers improved lion age estimates for population modeling and investigations of age-related mortality, and may assist national and international wildlife authorities in judging compliance with regulatory measures involving age.  相似文献   

18.
Lions were the most widespread carnivores in the late Pleistocene, ranging from southern Africa to the southern USA, but little is known about the evolutionary relationships among these Pleistocene populations or the dynamics that led to their extinction. Using ancient DNA techniques, we obtained mitochondrial sequences from 52 individuals sampled across the present and former range of lions. Phylogenetic analysis revealed three distinct clusters: (i) modern lions, Panthera leo ; (ii) extinct Pleistocene cave lions, which formed a homogeneous population extending from Europe across Beringia (Siberia, Alaska and western Canada); and (iii) extinct American lions, which formed a separate population south of the Pleistocene ice sheets. The American lion appears to have become genetically isolated around 340 000 years ago, despite the apparent lack of significant barriers to gene flow with Beringian populations through much of the late Pleistocene. We found potential evidence of a severe population bottleneck in the cave lion during the previous interstadial, sometime after 48 000 years, adding to evidence from bison, mammoths, horses and brown bears that megafaunal populations underwent major genetic alterations throughout the last interstadial, potentially presaging the processes involved in the subsequent end-Pleistocene mass extinctions.  相似文献   

19.
The use of transabdominal ultrasonography to assess the oestrous cycle has not been previously described in the African lion (Panthera leo). Twelve sexually mature lionesses and five female cubs had their reproductive organs assessed by transabdominal ultrasound. Ovarian findings were compared to laparoscopic findings while performing laparoscopic ovariectomy or salpingectomy. Vaginal cytology was performed and serum progesterone levels were determined. By combining all data the oestrous cycle stage of each lion was determined. One lion was far pregnant and was not operated on. In adults a uterine body could be seen ultrasonographically in 67% of lions while mural structures could be distinguished in 44% of lions. Five uterine horns could be seen in 3 lions. In 12 adults 10 ovaries were found of which eight had discernable follicles or luteal structures. During laparoscopy 12 active ovaries were seen with luteal structures seen in 11 ovaries and follicles in 2 ovaries. Using laparoscopy as the gold standard, ultrasonography had a sensitivity of 66% and specificity of 83% to detect ovarian reproductive activity. Two uterine cysts and a cluster of periovarian cysts were seen in three different lions. Three lions were pregnant, two were in oestrus, three in a luteal phase (dioestrus), and four were in anoestrus. Transabdominal ultrasound in combination with serum progesterone levels and vaginal cytology can be used to assess ovarian cyclical activity with reasonable accuracy in captive bred lions.  相似文献   

20.
We define African savannahs as being those areas that receive between 300 and 1,500 mm of rain annually. This broad definition encompasses a variety of habitats. Thus defined, savannahs comprise 13.5 million km2 and encompass most of the present range of the African lion (Panthera leo). Dense human populations and extensive conversion of land to human use preclude use by lions. Using high-resolution satellite imagery and human population density data we define lion areas, places that likely have resident lion populations. In 1960, 11.9 million km2 of these savannahs had fewer than 25 people per km2. The comparable area shrank to 9.7 million km2 by 2000. Areas of savannah Africa with few people have shrunk considerably in the last 50 years and human population projections suggest they will likely shrink significantly in the next 40. The current extent of free-ranging lion populations is 3.4 million km2 or about 25 % of savannah area. Habitats across this area are fragmented; all available data indicate that between 32,000 and 35,000 free-ranging lions live in 67 lion areas. Although these numbers are similar to previous estimates, they are geographically more comprehensive. There is abundant evidence of widespread declines and local extinctions. Under the criteria we outline, ten lion areas qualify as lion strongholds: four in East Africa and six in Southern Africa. Approximately 24,000 lions are in strongholds, with an additional 4,000 in potential ones. However, over 6,000 lions are in populations of doubtful long-term viability. Lion populations in West and Central Africa are acutely threatened with many recent, local extinctions even in nominally protected areas.  相似文献   

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