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1.
A population of rhesus monkeys (Macaca mulatta) at the ancient site of Tughlaqabad on the southern outskirts of New Delhi, India, showed moderate growth throughout the 1960s and 1970s and very rapid growth in the last 4 years. Between July 1980 and July 1983, the population increased 79%, from two groups of 160 monkeys to five groups of 286 monkeys, an average annual increase of 21.4%. The natality of the population has been high, averaging 82.4% over three birth seasons. Mortality and disappearance rates, especially of juveniles and adults, have been remarkably low with total annual mortality averaging only 3.7% from 1980 to 1983. We believe the striking record of population growth in this population can be attributed to total protection, abundant food, good cover, a lack of predators, a generally improving habitat, and low disease. With the right combination of ecological and behavioral factors, rhesus populations can double in four years. The Tughlaqabad population provides important guidelines for the restoration and conservation of primate populations.  相似文献   

2.
The Woodpigeon Columba palumbus population in a 1070 ha study area in East Anglia was studied from 1961 to 1986. This paper relates variations in Woodpigeon numbers to changes in the areas and types of crops grown. In the early 1960s the mean Woodpigeon population fluctuated between 60 and 112 birds per 50 ha during the winter months. Subsequently there was a steady decline until the population levelled out in the early 1970s at around 30 birds per 50 ha. From a very low point in 1977, the numbers of birds increased reaching in 1986 a mean of 55 birds per 50 ha. Marked changes occurred in the types of cereals grown in the area. In the 1960s spring-sown barley was the major crop with winter-sown wheat occupying most of the remaining area. Throughout the 1970s winter wheat was increasingly grown and winter-sown barley replaced the spring-sown variety. Although the area of permanent pasture did not change significantly, the area of clover ley was reduced markedly in the late 1960s. In the mid 1970s silage and oilseed rape were introduced and the cultivation of peas was expanded. On the basis of the crop types grown, the study period was divided into two 11-year blocks 1961–1971 and 1975–1985. Crop preferences of Woodpigeons were calculated for each month within each of these 11-year periods. A series of stepwise regressions was then conducted on both of the 11-year periods in order to see how well the areas of preferred crops in a particular month could account for the mean population size of that month. In the winters 1961/62 to 1971/72 the winter Woodpigeon population size was influenced by two crops. The area of cereal sowings largely determined how many birds remained in the area in December. The availability of clover ley, which depended upon both the area of clover ley and the amount of snow cover, controlled the population size in January and February. In the winters 1975/76 to 1985/86 the population size was again affected by two crops. In November the amount of grain on both stubbles and sowings influenced how many young birds stayed in the area. The area of oilseed rape in December then set the population size which changed very little throughout the rest of the winter. The change in the pattern of population regulation has profound implications for the likely success of shooting Woodpigeons in winter as a means of reducing local numbers.  相似文献   

3.
Tetanus was a major cause of mortality in the free-ranging population of rhesus monkeys (Macaca mulatta) on Cayo Santiago. From 1977 to 1984 the mean (±1 SD) annual total mortality rate (excluding neonatal deaths within 48 h postpartum, abortions, and stillbirths) was 6.39% ± .94%, and the mean annual tetanus mortality rate was 1.33% ± .45%. Tetanus deaths accounted for 19.5% of the total mortality in the colony. In 1985, all monkeys on the island, except infants and six adult monkeys, were given primary inoculations of tetanus toxoid. The following year, boosters were administered, and yearlings received primary inoculations. One fatal case of tetanus and one recovery from mild disease occurred in uninoculated adult monkeys in 1985, but no additional cases have been observed since. For 1985–1986 the mean annual total mortality rate was 3.69% ± .05%, and the mean annual tetanus mortality rate was .08% ± .08%. Thus, during the 2 years after inoculation against tetanus, the mean annual total mortality rate and the mean annual tetanus mortality rate declined by 42.2% and 94.0%, respectively, when compared to the 8-year period (1977–1984) prior to inoculation. These differences were significant [(χ2 = 12.48; P < .005), (χ2 = 16.94; P < .005)]. The elimination of tetanus infections through mass inoculation of the Cayo Santiago colony is expected to have a profound impact on the demography of the population by increasing the rate of population growth, by decreasing the differential rates of increase of the component social groups, and by changing the age distribution of the population.  相似文献   

4.
A survey of rhesus monkeys (Macaca mulatta) and hanuman langurs (Presbytis entellus) was conducted in urban and forest areas of Varanasi, India. Data were collected on group size and composition. Nine groups of rhesus monkeys inhabited various urban niches, but langurs were completely absent from urban areas. Approximately 159 rhesus monkeys and 720 langurs lived in the forested area. Both the urban and the forested habitats of this area are being reduced in size, and it is suggested that these populations be moved to nearby forest preserves.  相似文献   

5.
《Ostrich》2013,84(1-2):10-19
Long-term (1951–1985) data on the breeding waterbird populations and habitat modifications at Cape Flats sewage treatment works (Strandfontein) and Rondevlei Bird Sanctuary (Rondevlei) were assessed to establish the main factors affecting the breeding species richness and nest abundance. Fifty-two 'water-associated' breeding species were recorded in the Zeekoe River catchment waterbodies, 46 (88.5%) at Strandfontein, 38 (73.1%) at Rondevlei Bird Sanctuary (Rondevlei), 33 (63.5%) at Zeekoevlei and ten (19.2%) at Princess Vlei. Thirteen (25.5%) of the species were unique to Strandfontein and five (9.8%) to Rondevlei. Sorenson's similarity indices indicated high similarity (Cs = 0.81) in species richness and low similarity in nest abundance pattern (CN = 0.10) for the paired sites Strandfontein-Rondevlei. The lowest breeding species richness (11 species) was in winter (June) and the peak (42 species) was in spring (October). Twenty-four species joined the breeding population of Strandfontein during 1959–1976 (during which time pond water surface area increased 2372%). The mean breeding species richness increased significantly (χ 2 2 = 14.42, P <0.001) at Strandfontein during three distinctive periods: 1951–1958 (pre-construction), 1959–1976 (construction) and 1977–1985 (stabilization). At Rondevlei there were no significant differences in breeding species richness during the same periods. However, there were significant differences in the nest abundance pattern between these grouped years, both at Strandfontein (χ 2 2 = 1472.2, P <0.001) and at Rondevlei (χ 2 2 = 60.28, P <0.001). It is suggested that the same pool of species use the heterogeneous habitats at all the sites in the catchment according to their availability. The remarkable increase in species richness and nest abundance at Strandfontein after the late 1970s is attributed to higher habitat structural complexity, broad habitat types, stabilization and maturation of pond water and the subsequent increase in food diversity and availability. The decrease in Rondevlei nesting populations after the 1960s is probably related to fluctuations in water levels, cover of mudbanks with vegetation and high density of alien fish. A multipurpose management concept for conservation is proposed for the Zeekoe River catchment area. Strandfontein provides the greatest diversity of aquatic habitats not available elsewhere in the catchment (habitats for rare breeders such as Avocet, Black-winged Stilt, Red-billed Teal and some plovers) Rondevlei has a complementary habitat spectrum (suitable for Great Crested Grebe, Podiceps cristatus, Little Bittern, Ixobrychus minutus, and reedbed species). Zeekoevlei provides a large area of reedbed habitat for colonial breeding species (African Spoonbill and herons) and Princess Vlei is suggested for attracting Laridae.  相似文献   

6.
Mitochondrial DNA, purified from 36 samples of 23 local populations which are widely distributed in Vietnam, Burma, and 10 provinces of China, has been analyzed to model the phylogeny of rhesus monkeys. The 20 local populations of China may represent nearly all major populations in China. Using 20 restriction endonucleases of 6-bp recognition, we observed a total of 50–61 sites in the various samples. By combining the cleavage patterns for each enzyme, the 36 samples were classified into 23 restriction types, each of which was found exclusively in the respective population from which samples were obtained. By combining the earlier study of Indian rheusus monkeys, phylogenetic trees, which have been constructed on the basis of genetic distance, indicate that rhesus monkeys in China, Vietnam, India, and Burma can be divided into seven groups. Integrating morphological and geographical data, we suggest that rhesus monkeys in China, Vietnam, and Burma may be classified into six subspecies—M. m. mulatta, M. m. brevicaudus, M. m. lasiotis, M. m. littoralis, M. m. vestita, and M. m. tcheliensis-and rhesus monkeys in India may be another valid subspecies.M. m. tcheliensis is the most endangered subspecies in China. Divergence among subspecies may have begun 0.9–1.6 Ma. The radiation of rhesus monkeys in China may have spread from the southwest toward the east. The taxonomic status of the Hainan monkey and the Taiwan monkey require further investigation.  相似文献   

7.
Densities of microtine rodents in two habitat complexes in the tundra of Finnmarks-vidda, Norwegian Lapland, were studied during 1977-89 by means of snap trapping (Small Quadrat Method) Predator populations were studied by mapping breeding raptors and by snow-tracking small mustelids During 1977-85, snow-trackmg was conducted only during peak and decline years, whereas during 1986-89, snow-tracking was conducted every winter (November-December) and live-trapping (in August) was used as an additional method
Lowland vole populations had regular density fluctuations with peaks in 1978-79. 1982-84 and 1987-88 Highland vole populations fluctuated less regularly and at lower over-all densities Highland lemming populations had two outbreaks, in 1978 and 1988, ending in abrupt winter crashes In the lowland, outbreak levels were reached only in 1978 All microtine declines in relatively productive lowland habitats were accompanied by intense activity of small mustelids. whereas avian predators were common only in 1983 Lowland declines also showed clear between-habitat asynchrony they started in areas with an exceptional abundance of productive habitats and then spread to more barren areas These lowland data are consistent with the hypothesis of a mustelid-microtine limit cycle, although also several other hypotheses remain unrefuted The highland lemming data suggest a simple exploiter-victim interaction between lemmings and the vegetation  相似文献   

8.
Annual surveys in 1985–1987 revealed that, since 1975, the total population of the Tana River red colobus (Colobus badius rufomitratus)declined by approximately 80%. An intensive study in 1986–1988 of two groups of colobus in the Tana River Primate National Reserve indicated that habitat disturbance from the changing river course and shifting agricultural practices were primarily responsible for the decline. Clearcutting around Mchelelo forest in the late 1960s compressed colobus populations to levels probably above the carrying capacity. Between 1975 and 1986 primate population density declined dramatically, the number of red colobus groups in Mchelelo forest decreased by half, and the size of the remaining group was greatly reduced. In 1986, there were fewer solitary colobus and small parties in the forest, harem male takeovers did not occur, infant survivorship increased, and demographic parameters generally had improved. The colobus groups in Mchelelo in 1973–1975, living at higher densities, showed different feeding and ranging behaviors than 1986–1988 groups. Range size was smaller in 1975, range overlap occurred, and a greater portion of the forest was used per day and per month. Mature leaves accounted for a much higher proportion of the diet. Time spent feeding and resting was the same in both studies. Social organization in predominantly one- male groups was maintained and adult and subadult females transferred between groups.  相似文献   

9.
Prior to 1985 tetanus was a major cause of mortality in the free-ranging colony of rhesus monkeys on Cayo Santiago, accounting for almost a quarter of annual deaths. In 1985 and 1986 all animals (except infants) received primary and booster doses, respectively, of tetanus toxoid. In subsequent years primary immunizations were given to all yearlings, and boosters were administered to all 2-year-old animals during the annual capture of the colony. The main objectives of the tetanus immunization program were to reduce the pain and suffering caused by tetanus infections and to decrease mortality in the colony. Other objectives were to evaluate the efficacy of the two-dose tetanus toxoid immunization protocol and to determine whether additional boosters might be required to provide adequate long-term protection against tetanus infections. The immediate effect of the mass immunization program was the elimination of clinical tetanus infections in the population and a 42.2% reduction in the overall mortality rate. Since the immunization program began, no cases of tetanus have been observed in the colony, except in two unimmunized infants, and it has not been necessary to give tertiary injections of tetanus toxoid to maintain protection against infection. A sample collected in 2004 of the original cohort of monkeys immunized in 1985 and 1986 showed that 93.3% (14/15) had protective tetanus antibody titers (>0.01 IU/ml) at the ages of 20-23 years, which is close to the life expectancy of the Cayo Santiago rhesus macaques. Two intramuscular doses of tetanus toxoid provided long-term, if not lifelong, protection against tetanus for rhesus monkeys living in a tropical clime where tetanus is enzootic and the risk of infection is great.  相似文献   

10.
An isolated population of rhesus monkeys living in Xinglung County, north of Beijing (latitude 40⪤gree N), was a natural population at the northernmost range of the species in Asia. Rhesus had been reported there at the end of the last century, based on a few specimens, but were not well known by zoologists until the beginning of the 1960s. The population remained approximately 50–60 individuals in the 1960s but then declined to only 4 or 5 monkeys about 5 years ago. It has been confirmed by local hunters and two recent field trips that the population is now probably extinct. As a result, the northern extent of the remaining natural range of the rhesus macaque in Asia has dropped 650 km southward to the Jiyuan Nature Reserve on the border of Hunan and Shanxi provinces, just north of the Yellow River.  相似文献   

11.
This set of cross‐sectional and longitudinal data from children and young adults in certain Bougainville and Solomon Islands populations undergoing rapid modernization during the period 1966–1986 reveals very different responses to essentially the same stimuli—the introduction and widespread availability of western dietary items and reductions in habitual activity. Our analyses of over 2,000 children and young adults first measured in 1966–1972, with follow‐up surveys in 1968–1970 and 1985–1986, show changes in overweight/obesity in these communities have their onset around puberty, and are not related to differences in childhood growth stunting. The prevalence of overweight and obesity increased substantially during the period of this study among young adults, particularly women, and in groups with more Polynesian affinities, where the frequency of overweight (BMI ≥ 25) tripled over this 20‐year interval. However, the BMI of the more Papuan groups on Bougainville remained remarkably stable, even though they were close to the epicenter of modernization during this period, the Bougainville Copper Mine. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

12.
Five hundred forty-five serum samples from rhesus monkeys imported to the Sukhumi monkey nursery from India, China, and Viet-Nam were investigated by the starch gel electrophoresis method. A high level of transferrin polymorphism was noted, 11 alleles and 38 phenotypes being detected.Statistical verification of transferrin distribution correspondence to theHardy-Weinberg equation revealed a statistically significant excess of monkeys with Tf DD in the Vietnamese group and in the group of monkeys imported from India in 1950–1968. The adaptive advantage of monkeys with this phenotype is believed possible. Analysis of genetical dissociation makes it possible to suggest that there exist two populations of rhesus monkeys, namely, the Chinese-Vietnamese and Indian.  相似文献   

13.
Eighty-two percent of a group of rhesus monkeys removed from Cayo Santiago were seropositive for B virus (Herpesvirus simiae) antibodies. Similar results were obtained from the Cayo Santiago macaque population two decades ago and from feral Indian rhesus monkeys. Thus it is likely that B virus has been enzootic in the Cayo Santiago population since 1938, when the colony was established with stock imported from India.  相似文献   

14.
Four aerial survey projects were conducted between 1977 and 1986 to determine the abundance, density and distribution of West Indian manatees (Trichechus manatus), in the northern Banana River, Kennedy Space Center, Florida. Manatee density and distribution within selected portions of the 78.5 km2 study area were determined. Peak numbers of manatees occurred in spring of each year. The maximum counts increased from 56 in 1978 to 297 in 1986. Manatee abundance was lowest in the winter of each year. Mean density per flight increased from 0.52 manatees/km2 in 1977–78 to 2.73/km2 in 1984–86. This increase may reflect increases in the east coast population or shifts in the population distribution. Distributional changes were observed in the study area through time, with a lower percentage of manatees occurring in industrial areas and a correspondingly higher percentage of manatees in nonindustrial areas by 1985.  相似文献   

15.
Corynebacterium pseudotuberculosis causes caseous lymphadenitis, a disease primarily affecting sheep and goats which occurs as a chronic infection characterized by suppurative lymphadenitis (Lovell 1959, Marsh 1965, Jubb & Kennedy 1970, Ayers 1977, Addo & Eid 1978). The disease has an insidious nature and a high prevalence, resulting in large economic losses due to condemnation of carcasses and organs at slaughter (Turner 1973).  相似文献   

16.
西藏哺乳类名录   总被引:4,自引:0,他引:4  
十九世纪30-40年代,曾一度旅居尼泊尔的霍奇森(Hodgson),通过各种渠道获得一批西藏标本。本世纪初,沙俄军官科兹洛夫(1901)率“探险队”入藏考察;沃尔顿(Walton,1903,1904)随英军到藏南收集动物标本;沃拉斯顿(Wollaston,1921)以及路德洛(Ludlow,1932,1934,1938,1946-1947)等,相继在藏南(包括珠穆朗玛峰地区)、藏东南和藏西北等地区调查采集。  相似文献   

17.
Continuing investigations on the South Amherst Drosophila melanogaster natural population following the significant decline and recovery of lethal (le) and semilethal (sle) frequencies in the late 1960's (Ives, 1970) show that the population has been remarkably stable although it contains MR (male recombination) and/or P DNA elements (Kidwell et al., 1977a; Green, 1980). A 13-year study affirms that the lethals present are nonrandomly distributed along the second chromosome and deficient on the right; they differ significantly in distribution from spontaneous (Ives, 1973) and δ-induced lethals (Minamori and Ito, 1971). Between 1970 and 1977, a total of 4,083 second chromosomes from the Markert subpopulation were analyzed; 28.9% of the chromosomes were lethal and 7.25% were semilethal in homozygous condition. Frequencies are similar for early summer and late fall collections although the rate of allelism among lethals is significantly higher in early summer than in late fall. For the large fall (1970–1979) Porch site population, 2,519 second chromosomes were analyzed; 29.5% were lethal and 8.0% were sublethal as homozygotes; the rate of allelism among lethals was 1.50%. At Hockanum, 1977–1983, lethal and semilethal frequencies were lower; the rate of allelism among lethals was 1.43%. The chromosome map distribution of lethals does not change between summer and late fall at Markert. The overall distributions of lethals at the Markert and Hockanum sites are similar. In tests for male recombination (MR) activity in the population over a 6-year period, a total of 0.47% recombinants were observed; these were uniformly distributed along the second chromosome. Comparisons are made with other long studied D. melanogaster populations.  相似文献   

18.
Because wild rhesus macaque (Macaca mulatta) populations have suffered major declines, there is a growing need to characterize their genetic and population structure in order to protect the genetic integrity of this species. In this study, we genotyped a sample comprising 120 wild rhesus macaques from six sites in Sichuan Province for 30 nuclear microsatellite (STR) loci using an ABI 3130xl genetic analyzer. Bayesian analyses and PCA clearly differentiated monkeys from Heishui from those at other sites. The samples from all six sites exhibited high gene diversity suggesting that the Sichuan wild rhesus macaque populations are not threatened by a lack of genetic diversity. Deviation from Hardy–Weinberg equilibrium was more frequent in the Danba and Heishui populations. This may be due to the more fragmented habitat and less disturbance by humans in this area that foster greater subpopulation structuring than occurs in eastern China. We suggest that this population subdivision is the result of both long-term geographic barriers and human activity.  相似文献   

19.
Six villages in upland West Bengal, India were resurveyed in 1987 and the results compared with the data from a larger area studied in 1977–1978. There has been a 6.4% increase in the human population, but the number of households has decreased 1.7%. The cattle population has increased 14.4% with male cattle accounting for the bulk of the increase. A crossbreeding program implemented 8 years ago has had virtually no beneficial effects. Other observations on the general welfare of humans and domestic animals are presented.This research was funded by a 1986–1987 Fulbright Award.  相似文献   

20.
This study investigates changes in the prevalence of linear enamel hypoplasia (LEH) before and after the shift from irregular to regular provisioning in the Cayo Santiago rhesus monkey population. Prior to 1956, monkeys on this island colony did not receive consistent provisions, and were reported to be in poor health (Rawlins and Kessler [1986] The Cayo Santiago Macaques; Albany: State University of New York Press). A regular provisioning program, instituted in August 1956, resulted in the improved health of individuals and the growth of the population (Rawlins and Kessler [1986] The Cayo Santiago Macaques; Albany: State University of New York Press). LEH, a developmental defect of enamel, is a sensitive indicator of systemic physiological stress (Goodman and Rose [1990] Yrbk. Phys. Anthropol. 33:59-110). It was therefore hypothesized that the prevalence of LEH would be higher in monkeys who were irregularly provisioned than in monkeys who experienced regular provisioning. To test this hypothesis, teeth were examined for LEH in a sample of 181 female rhesus monkeys. The results support the hypothesis: the mean number of defects was statistically significantly higher in the preprovisioned group than it was in the postprovisioned one. When LEH prevalence was assessed using only defects occurring on antimeric pairs, the preprovisioned group again had a higher prevalence than the postprovisioned one, although the difference was not statistically significant, most likely because of the reduced sample size. The results of this study indicate that changes in LEH prevalence, at least in this population of rhesus monkeys, are associated with changes in nutritional status.  相似文献   

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