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1.
This pilot project began establishing a nutritional profile for free‐ranging giraffe. The results will be used as a tool to begin assessing the nutritional status of captive giraffe. In October 2004 serum samples were collected opportunistically from seven adult and 17 sub‐adult giraffe being anesthetized for different studies. Seventeen animals were from Double Drift Game Reserve and seven animals were from Kariega Private Game Reserve. The serum samples were analyzed for circulating concentrations of amino acids, fatty acids, lipoproteins, vitamins, and minerals. Information from 15 serum samples collected from anesthetized giraffe in Kruger National Park during April and August 2003 was included in the calcium and phosphorus concentration data. No significant differences were identified between genders. Significant differences between locations were identified for concentrations of certain amino acids, fatty acids, and lipoproteins. Differences between locations are likely due to different nutrient concentrations of foods and possibly the result of different animal densities forcing different food choices among locations. This pilot project may expand to include changes in circulating nutrient concentrations for free‐ranging giraffe as is influenced by other locations, seasonal food availability, and different giraffe subspecies. Zoo Biol 0:1–13, 2007. © 2006 Wiley‐Liss, Inc.  相似文献   

2.
During a 3-year study in Nairobi National Park, 1965–1968, 250 giraffe were identified by their neck markings. The herd structure of these animals was studied, including the relationships between particular individuals. Population information collected included the times of calving, the growth and longevity of giraffe, their reproductive potential, the age structure of the population and its density. Immigration, emigration and home range studies were completed with the help of radio telemetry equipment. The effect of giraffe on the vegetation and the possibility of giraffe surviving without free water are discussed.  相似文献   

3.
Giraffe were historically free‐ranging across most of sub‐Saharan Africa but are now most often confined to national parks, conservation areas, or private ranches. Five viable populations of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) remain in protected areas in Kenya and Uganda. The viable population in Uganda is Murchison Falls National Park and the four populations in Kenya are Lake Nakuru National Park (LNNP), Ruma National Park, Giraffe Manor, and Mwea Natural Reserve. The Kenya Wildlife Service queried a rapid decline in LNNP giraffe numbers falling from 153 individuals (1995) to 62 individuals (2002) and the failure of that population to recruit young in those years. Significantly reduced browse options, inbreeding depression and preferential lion predation were considered as potential reasons for this trend. Population genetic parameter estimates derived from multilocus genotype analyses suggest that the LNNP population was in good genetic health with respect to the likelihood of inbreeding depression. The population decline coincided with the drought attributed to the 1994 El Niño. Possible dietary complications from highly concentrated tannin levels because of forced over consumption of the park’s declining acacia trees may have compromised young giraffe, making them easy and opportunistic prey for the park’s lion population.  相似文献   

4.
The iconic giraffe, an ecologically important browser, has shown a substantial decline in numbers across Africa since the 1990s. In Serengeti National Park, Tanzania, giraffes reached densities of 1.5–2.6 individuals km−2 in the 1970s coincident with a pulse of Acacia tree recruitment. However, despite continued increases in woody cover between the 1980s and the 2000s, giraffe recruitment and survival rates have declined and density has dropped to only 0.3–0.4 giraffes km−2. We used a decision table to investigate how four extrinsic factors may have contributed to these declines: food supply, predation, parasites, and poaching, which have all been previously shown to limit Serengeti ungulate populations. Lower recruitment likely resulted from a reduction in diet quality, owing to the replacement of preferred trees with unpalatable species, while decreased adult survival resulted from illegal harvesting, which appears to have had a greater impact on giraffe populations bordering the western and northern Serengeti. The Serengeti giraffe population will likely persist at low-to-moderate densities until palatable tree species regain their former abundance. Leslie matrix models suggest that park managers should meanwhile redouble their efforts to reduce poaching, thereby improving adult survival.  相似文献   

5.
The giraffe restraint device manufactured at the Cheyenne Mountain Zoo has the capability to fully support the weight of an immobilized adult giraffe in an upright posture and allow physical restraint of giraffe. The unit has been used for either chemical or physical restraint 74 times, in 22 months, on seven different adult giraffe, without animal or personnel injuries. Habituation and desensitization of the giraffe are critical prerequisites for the successful use of the giraffe restraint device. Yohimbine effectively reversed the effects of xylazine sedation of giraffe. A drug combination of detomidine and azaperone offers promise as an alternative to either physical restraint or immobilization of giraffe for selected clinical and investigative procedures. Using the restraint device it has been possible to perform tuberculin testing, venipuncture, vaginal examination, rectal palpation, rectal ultrasound, cervical catheterization, hoof-trimming, and placement of a hoof block on awake, habituated, and desensitized giraffe.  相似文献   

6.
In the context of a broader ecological investigation, food habits of giraffe were studied in Tsavo National Park (East). The only method employed was direct observation of feeding animals in the field. Each instance in which one animal fed on one individual plant was counted as one food record for this plant species; 4025 records are analysed. A total of sixty-six plant species was found to be eaten, the great majority being trees and shrubs, with a few creepers and vines. There were marked seasonal differences in the diet of giraffe, deciduous trees, shrubs and vines being dominant in the green season, evergreen plants (partly in riverine forest) in the dry season. All the trees and larger shrubs common in the study area were eaten by giraffe, while few records for very small shrubs and none for herbs and grasses were obtained. An analysis of the available vegetation was made in part of the dry-season habitat, and for twenty species the frequency in the habitat was compared with the frequency in the giraffe's diet, revealing selection for or against certain species. Giraffe utilized the upper vegetation layers, where available, but overall c. 50% of all browsing was below 2 m above ground, i.e. within reach of smaller browsers. Results of this study are compared with what is known on food habits of giraffe in other areas. Possible competition of giraffe with other browsers and the relationship between giraffe and their habitat are discussed. Continued survival of giraffe, and other browsers, in Tsavo National Park depends primarily on (1) adequate control of fire, and (2) the impact of future vegetation changes on the amount and variety of available browse plants.  相似文献   

7.
Censuses indicated similar elephant densities in some habitats to those in certain other East African Parks where woodland has been almost completely destroyed. Giraffe densities were low. Herd structure indicated a healthy elephant population; but poor recruitment in the giraffe population. Policy for the national parks is discussed. It is suggested that it is not in the interests of Uganda or science to allow Kidepo Valley Park to become dominated by elephant in the same way as Kabalega and Rwenzori Park. Evidence that this is happening under current elephant use is strong. Cropping of two thirds of the elephant in the Narus valley is recommended. The revenue from cropping should be used for essential fire control measures and for a monitoring programme to ascertain optimum elephant numbers. Elephant should not be cropped in the absence of fire control.  相似文献   

8.
In cohesive social groups, travel progressions are often led by dominant or older individuals, but the leadership traits of individuals residing in flexible social systems are poorly known. Giraffe reside in herds characterized by fission–fusion dynamics frequently mediated by kinship. We analyzed 41 years (1971–2012) of longitudinal data collected from a community of Thornicroft's giraffe (Giraffa camelopardalis thornicrofti) living around South Luangwa National Park, Zambia, to assess the characteristics of herd leaders. Movement of giraffe in a single file progression was not associated with either season or time of day, but progressions were significantly more likely to occur when giraffe traveled in open areas. The oldest female in a herd was significantly more likely to be at the front position than expected, occupying the leadership niche on 79% of observations. We reason that matriarchal leadership in giraffe, as in African elephants, Loxodonta africana, is associated with resource learning. Giraffe societies are constructed on a heretofore unrecognized foundation that integrates relatedness and familiarity with matriarchal leadership in herd movement.  相似文献   

9.
Two geographically distinct populations of giraffe (Giraffa camelopardalis) were sampled for this study, the northern Namib Desert and Etosha National Park. Population genetic parameters and relationships within subpopulations were estimated to better understand the genetic architecture of this isolated subspecies. Gene flow between the geographically separated populations can be attributed to recent translocation of giraffe between the two populations. Inbreeding estimates in the six subpopulations studied were low though we found evidence that genetic drift may be affecting the genetic diversity of the isolated populations in northern Namibia. Population dynamics of the sampling locations was inferred with relationship coefficient analyses. Recent molecular systematics of the Namibian giraffe populations indicates that they are distinct from the subspecies Giraffa camelopardalis giraffa and classified as G. c. angolensis. Based on genetic analyses, these giraffe populations of northern Namibia, the desert‐dwelling giraffe and those protected in Etosha National Park, are a distinct subspecies from that previously assumed; thus we add data on G. c. angolensis to our scientific knowledge of this giraffe of southern Africa.  相似文献   

10.
Association partners of young chimpanzees at the Mahale Mountains National Park were analyzed. Juvenile and adolescent chimpanzees associated frequently with their mothers, although mother-offspring association decreased as the offspring grew up. Males tended to leave their mothers and associate with adult males, while females remained frequently associating with their mothers in early adolescence. In late adolescence and young adulthood, males usually associated with adult males and cycling adult females. Females may transfer into neighboring unit-groups in this stage. Although an immigrant female tended to be alone when her estrous cycle stopped, she associated with many individuals, in particular with adult males, when she resumed cycling. Some orphans were observed to associate frequently with particular adults. The findings were discussed in relation to the unique characteristics of chimpanzee social system.  相似文献   

11.
12.
Thornicroft's giraffe, Giraffa camelopardalis thornicrofti, is a geographically isolated subspecies of giraffe found only in north‐east Zambia. The population only occurs in Zambia's South Luangwa Valley, an area which interestingly places it between the current distribution of Masai (G. c. tippelskirchi) giraffe to the north, and the Angolan (G. c. angolensis) and South African (G. c. giraffa) giraffe in the south‐west and south, respectively. Specific studies have been undertaken on the ecology of this subspecies, but their population genetics remains unknown. We studied 34 individuals from the South Luangwa National Park and adjacent Lupande Game Management Area and seven individuals from northern Botswana. The complete cytochrome b and control region sequences of the mitochondrial genome were sequenced and analysed together with database data by maximum likelihood tree reconstruction and maximum parsimony network analyses. The giraffe from Zambia's South Luangwa Valley are most closely related to the subspecies G. c. tippelskirchi and part of their radiation. However, they form a unique population that would benefit from increased research and conservation management.  相似文献   

13.
A herbivore can manipulate certain factors of its feeding behaviour in order to achieve the metabolic requirements for reproduction. These factors include the choice of habitat in which to feed, the selection criteria for choosing food items, and the time allocated to feeding or devoted to other energy-consuming activities. The manipulation of these behavioural factors by giraffe in the Serengeti National Park, Tanzania is analysed in relation to the seasonal changes in the quantity and quality of the food resource.
The pattern of habitat choice demonstrates seasonal movements by giraffe across the drainage catena in response to differences in the rates of browse production between woodland types.
Giraffe show a positive inter-specific selection for the minor food items with a low available biomass, and utilize the dominant species in approximate proportion to their availability. Plant part selection is shown for the flushing shoots with very high protein contents.
Selection criteria include a significant selection for phosphorus, and in the dry season a selection for high energy material by breeding females. With the high nutritional qualities of the diets, negative criteria such as secondary chemical compounds are important. Patterns of browse selection are correlated with inter-specific seasonal changes in plant phenology.
Giraffe devote more time to foraging as the biomass and quality of the food declines in the dry season. Energy is conserved by minimizing energy-consuming activities at the most demanding times of day.  相似文献   

14.
A squeeze cage at Woodland Park Zoo has become a valuable tool in giraffe management. The cage has been used 63 times in 4 years with no serious injuries to animals or personnel. Conditioning the giraffes to the cage is of foremost importance in planning a successful restraining procedure. Individual giraffes react differently to the stress of being confined, so careful monitoring of behavior throughout is imperative to anticipate and prevent potential problems. Staff should be fully trained in the use of the equipment and familiar with the temperament of the giraffe. The cage is used for hoof trimming and routine medical examinations, including blood collection, X-rays, and giving injections.  相似文献   

15.
Patella ferruginea is the most endangered endemic marine invertebrate of western Mediterranean rocky shores. From 2012 to 2015, we performed a census and an ecological study for this gastropod mollusc in the Zembra Archipelago National Park in Tunisia, where a large population still remains. In 1986, a total of 20,000 individuals were estimated, with 0.7?ind/m2, 4.4?cm adult mean size and low recruitment rate. In 2009, the estimated population reached 38,559 individuals with 2.65?ind/m2, 5.42?cm adult mean size and high recruitment rate. During the present work, 43,790 individuals were estimated in 2012, 27,359 in 2013, 33,170 in 2014 and 40,404 in 2015, with an average density ranging from 0.1 to 8.5 individuals per square metre, but reaching as many as 25?ind/m2 on some shores. This makes the archipelago one of the most important Mediterranean ‘hot spots’ for P. ferruginea, as it has a large and well-conserved population of this species. Variability of the population size is influenced by various biotic and abiotic factors, but is principally impacted by poaching of the species. The poachers target individuals larger than 6?cm in length, and the sex ratio study has shown that over 70% of individuals become females at that size. In addition, high recruitment rates were recorded in 2012 and 2013, but these decreased in 2014 and 2015, although population numbers show the opposite pattern. Moreover, growth rate is low and P. ferruginea may need many years to reach a large adult size. The loss of reproductive potential due to poaching inevitably causes a significant imbalance in the limpet population. Our results indicate the importance of the National Park for P. ferruginea and underline the need for this species to be protected and monitored over a long period to provide the most appropriate management measures.  相似文献   

16.
Giraffes (Giraffa camelopardalis) are often stated to be unable to swim, and while few observations supporting this have ever been offered, we sought to test the hypothesis that giraffes exhibited a body shape or density unsuited for locomotion in water. We assessed the floating capability of giraffes by simulating their buoyancy with a three-dimensional mathematical/computational model. A similar model of a horse (Equus caballus) was used as a control, and its floating behaviour replicates the observed orientations of immersed horses. The floating giraffe model has its neck sub-horizontal, and the animal would struggle to keep its head clear of the water surface. Using an isometrically scaled-down giraffe model with a total mass equal to that of the horse, the giraffe's proportionally larger limbs have much higher rotational inertias than do those of horses, and their wetted surface areas are 13.5% greater relative to that of the horse, thus making rapid swimming motions more strenuous. The mean density of the giraffe model (960 gm/l) is also higher than that of the horse (930 gm/l), and closer to that causing negative buoyancy (1000 gm/l). A swimming giraffe - forced into a posture where the neck is sub-horizontal and with a thorax that is pulled downwards by the large fore limbs - would not be able to move the neck and limbs synchronously as giraffes do when moving on land, possibly further hampering the animal's ability to move its limbs effectively underwater. We found that a full-sized, adult giraffe will become buoyant in water deeper than 2.8 m. While it is not impossible for giraffes to swim, we speculate that they would perform poorly compared to other mammals and are hence likely to avoid swimming if possible.  相似文献   

17.
18.
J. B. Foster    M. J. Coe 《Journal of Zoology》1968,155(4):413-425
The large animals of Nairobi National Park have been censused intermittently once a month from mid-1960 until the end of 1966. Of the 23 species discussed, the density per kilometre has been determined accurately for the following: Grant's gazelle, Thomson's gazelle, water-buck, impala, wildebeest, hartebeest, eland, buffalo, warthog, giraffe, zebra and ostrich. From these figures the biomass has been calculated for each species each year. After a peak biomass of 12,775 kg/sq. km during the drought of 1960–61 the population declined to and remained fairly level at about 5690 kg/sq. km from 1962 to 1966. This figure includes about 1050 kg/sq. km of cattle and sheep. The large predators account for only about 1.4 % of the total biomass of wild animals while removing about 15.5% from this group annually.  相似文献   

19.
We describe dental microwear in baboons (Papio hamadryas sensu lato) from the anubis-hamadryas hybrid zone of Awash National Park, Ethiopia, outline its variation with sex and age, and attempt to relate the observed microwear pattern to environment and diet. Casts of the maxillary second molar of 52 adult and subadult individuals of both sexes were examined with a scanning electron microscope at x 500. Digitized micrographs were taken at a consistent location on facet 9, and microwear was recorded with an image analysis software package. Univariate and multivariate statistics were used to investigate the shape, size, and density of microwear features. The overall pattern of microwear exhibits an unusual combination of high feature density, with numerous small pits and relatively wide striations, and a high correlation between width of pits and striations across individuals. We interpret this pattern as predominantly the consequence of abrasion by relatively small-caliber environmental grit when accidentally ingested with tough foods such as dried seeds and fruits, as expected in a terrestrial omnivore living in a dusty habitat. Statistical analysis revealed no significant differences between groups defined by sex, age, or troop membership, a result consistent with qualitative observations of feeding habits in this population, and which lends no support to the hypothesis that the longer jaws of adult males should result in longer striations. A trend towards greater feature density in females, however, might be due to limited sexual dinichism, and merits further investigation.  相似文献   

20.
Antler growth and form was examined for a sample of 303 sika stags (Cervus nippon) culled over an eight-year period from a feral population in Killarney National Park, County Kerry, Ireland. Most antler measurements taken were highly correlated with each other and growth was complete after the sixth year. Few abnormalities were recorded and the degree of asymmetry in structure was less than previously reported for other sika populations. Variability in structure decreased with age and there was no effect of year of birth or cull on antler size for either adult or yearling stags. The growth pattern was similar to that of other populations except that the proportion of 'eight pointers' was low. An examination of antler damage was used to estimate fighting frequency across age classes. The results are discussed in relation to the genetic history of the herd and the use of antlers as weapons for intra-specific combat.  相似文献   

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