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1.
We documented the occurrence and abundance patterns of Angola black-and-white colobus (Colobus angolensis palliatus) in 46 coastal forest fragments ranging from 1 ha to >1400 ha in the Kwale District, Kenya. In field surveys conducted in
2001, we also recorded forest spatial, structural, resource, and disturbance characteristics to determine the effects of habitat
quality and fragmentation and the factors most critical to the continued survival of the little-known species. We tested 13
hypotheses to explain variation in patch occupancy and abundance patterns of Colobus angolensis palliatus in relation to habitat attributes. Minimal adequate models indicated that the occurrence of colobus in forest fragments is
positively associated with fragment area and canopy cover, whereas the density of colobus in occupied fragments is attributable
to forest area, the proportion of forest change over the previous 12 yr, and the basal area of 14 major food trees. Large-scale
illegal extraction of major colobus food trees in the District for human resource use, in both protected and unprotected forests,
together with ongoing forest clearance and modification, are the major threats to Colobus angolensis palliatus in Kenya. 相似文献
2.
The effects of human activity on population and social structure are a pantropical concern for primate conservation. We compare census data and social group counts from two forests in the Udzungwa Mountains, Tanzania. The main aim is to relate differences within and between the forests to current theory on the effect of human disturbance on primate abundance and group size. The survey reveals the presence of the restricted-range red colobus, Procolobus gordonorum, in New Dabaga/Ulangambi Forest Reserve (NDUFR). The primate community of NDUFR is impoverished compared to that in Ndundulu forest. Red colobus and black-and-white colobus (Colobus angolensis palliatus) abundance and group size are lowest in NDUFR. Fission-fusion of red colobus social groups may be occurring in previously logged areas of both forests. Our observations are consistent with current theory on the effect of habitat degradation and hunting on primates, but the relative effects of the 2 factors could not be differentiated. We pooled the results with previous data to show that abundance of red colobus in the Udzungwa Mountains is lowest at high elevations. Low red colobus group sizes appear to be related to human activity rather than elevation. Black-and-white colobus and Sykes monkeys (Cercopithecus mitis) show no relationship with elevation. Future studies will require more detailed information on vegetation, diet and ranging patterns to interpret fully intraspecific variation in population demography and social structure in the Udzungwa Mountains. 相似文献
3.
Monica M. McDonald Scott M. Johnson Edward R. Henry Pamela M. K. Cunneyworth 《American journal of primatology》2019,81(6)
Ecological niche models can be useful for clarifying relationships between environmental factors and a species’ geographic distribution. In this study, we use presence‐only data and environmental layers to create an ecological niche model to better understand the distribution of the East African Angolan black and white colobus monkey, Colobus angolensis palliatus, and to assess whether the model supports considering the population as two separate subspecies, Colobus angolensis sharpei and C. a. palliatus. We found the range of the predicted distribution for suitable habitat of C. a. palliatus as currently classified to be only 12.4% of that shown in the International Union for Conservation of Nature Red List range map and to be fragmented. As C. angolensis is considered a “Least Concern” species, this difference suggests that generalized maps may lead to understating the species’ extinction risk. When presence points were divided into two previously proposed subspecies —C. a. palliatus (Kenya and Northern Tanzania) and C. a. sharpei (Southern Tanzania)—we found significant environmental differences between the distributions. The most important ecological variable for C. a. palliatus was predominantly precipitation of the driest month (69.1%) whereas for C. a. sharpei annual precipitation (44.8%) and land cover (normalized difference vegetation index, 16.4%) were the most important. When comparing suitable ranges for the separate distributions, we found only a 1.2% geographical overlap. These differences are consistent with previous subspecies delineations of C. a. palliatus and C. a. sharpei based upon morphology, pelage, and genetics. Our study suggests that extirpation of C. a. palliatus in suitable habitat areas and occurrence of this subspecies in anthropogenic environments, warrant further consideration for conservation actions. 相似文献
4.
Claudia Barelli Valentina Oberosler Nathalie Cavada Arafat S. Mtui Steven Shinyambala Francesco Rovero 《Biotropica》2023,55(3):617-627
Anthropogenic activities driving tropical forests' loss imperil global biodiversity and provision of ecosystem services. In this context, systematic monitoring programs evaluating wildlife trends are essential. Non-human primates are relevant conservation targets since they represent vital components of tropical forests by serving as pollinators and seed dispersers. Here, we present primate group counts data collected over 19 years in a primate hotspot in Tanzania. We analyzed data with a hierarchical dynamic model accounting for imperfect detection that estimates local group abundance and temporal rates of change, to assess whether habitat protection explained trends of the arboreal and diurnal Peters' Angola colobus (Colobus angolensis palliatus), Udzungwa red colobus (Piliocolobus gordonorum), and Tanzania Sykes' monkey (Cercopithecus mitis subsp. moloneyi). We targeted populations occurring in two forest blocks with contrasting protection regimes, with one block impacted by targeted poaching of the two Colobus species. We found that these latter species were much less abundant in the more human impacted forest, underwent a rapid decline, and subsequently remained at low abundance and without signs of recovery once this forest was granted greater protection. Instead, Sykes' abundance did not differ between forests, and improved protection was associated with a slight increase in abundance. Age class composition for social groups of both Colobus species differed between forests, indicating altered births and survivorship rates in the impacted forest. Results suggest that targeted hunting can prevent recovery for several years and even after increased habitat protection. Our approach appears valuable to monitor population dynamics over the long term, highlighting species-specific variations in both vulnerability to anthropogenic disturbance and recovery patterns in primate populations. 相似文献
5.
We considered the relationship between dental sexual dimorphism and diet in 542 specimens of olive, red, and black-and-white
colobus. Using univariate statistical techniques, we examined 41 measurements of the maxillary and mandibular dentitions.
The results reveal two trends of dental sexual dimorphism in black-and-white colobus wherein (i) maleColobus guereza andC. angolensis are generally larger than females throughout the dentition and (ii)C. satanas and, to a lesser degree,C. polykomos exhibit reduced sexual differences in the canine base and females are slightly larger than males in noncanine dimensions.
Females of the red colobus,Procolobus (Piliocolobus) badius, are slightly larger than males in most noncanine measurements but canine sex differences are more pronounced than those
of black-and-white colobus.Procolobus (Procolobus) verus, the olive colobus, is characterized by some of the largest canine sex differences, yet the sexes do not differ much in noncanine
mean values. When patterns of sexual dimorphism are considered in terms of specific ecology and behavior, it is possible to
relate sex differences, in part, to known dietary differences. For example, overall dental morphology and the trend of sexual
differences inC. satanas andC. polykomos seem to be associated with the consumption of a diet rich in seeds. The pattern of dental sexual dimorphism inC. badius may also be influenced by dietary factors in that their patrilineal social organization could restrict female access to certain
foods thereby affecting rates of attrition and creating selection pressure for larger teeth. Relatively less is known of the
ecology and social organization ofP. verus but their dental sexual dimorphism is possibly less related to dietary factors than is the case for red or black-and-white
colobus. 相似文献
6.
Little is known about genetic variation in the 6–8 subspecies of Colobus angolensis, currently distinguished by pelage differences. We present a comparative genetic analysis of one of these subspecies, C. a. palliatus, in Kenya and Tanzania that assesses evolutionary relationships and patterns of mitochondrial genetic diversity in 103 individuals across its geographic range. Fecal samples from approximately 156 individuals were collected in four localities: (1) Diani Forest, Kenya; (2) Shimoni, Kenya; (3) Udzungwa Mountains National Park, Eastern Arc Mountains, Tanzania; and (4) Mount Rungwe, Southern Highlands, Tanzania. These samples represent at least six groups, with 5–15 samples from each. Comparative sequence analysis of a 1,795 base pair mtDNA fragment revealed 19 unique haplotypes in four populations. Phylogenetic analyses suggest that sampled Kenyan haplotypes are paraphyletic, with one Kenyan haplotype basal to all other sampled haplotypes. Analysis of molecular variance (AMOVA) suggests high levels of genetic variation among populations (ΦST 0.72, P<0.001). Genetic data are concordant with a subspecies level differentiation between C. a. palliatus populations in Kenya and those in Central and southern Tanzania, as earlier suggested based on pelage differences. This study highlights the evolutionary distinctiveness of Kenyan populations of C. a. palliatus relative to Tanzanian populations. Although C. a. palliatus habitat in Tanzania is currently better protected than in Kenya, our results suggest Kenyan and Tanzanian populations should be considered distinct units, and the protection of C. a. palliatus habitat in Kenya, as well as habitat connectivity between Kenyan populations, should be prioritized for conservation and management. Am. J. Primatol. 72:715–724, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
7.
The Angola black-and-white colobus (Colobus angolensis palliatus) is a flagship species for Kenya's coastal forests, a global biodiversity hotspot and a region for "priority" conservation investment. This study provides the first evaluation of colobus distribution, status, and current threats within its Kenyan range: the southern coastal District of Kwale. Line transect and sweep count surveys were carried out between July and November of 2001, covering 25,514 ha of coastal forest within 124 forest fragments. A total of 55 colobus populations were located, with total Kenyan C. a. palliatus population estimates ranging between 3,100 and 5,000 individuals (560-900 groups). The Shimba Hills National Reserve protects both the largest forest and largest colobus population in the District. A total of 3,000 ha of coastal forest (12%) still remain unprotected and provide critical habitat for over 17% of the national colobus population. The Diani and Shimoni forests in particular, are highlighted as key habitat for future colobus (and coastal forest) conservation initiatives. Local semistructured interviews and archival research into the historical distribution of the taxon in North Coast Kenya confirmed its occurrence (and subsequent range contraction) in the Kilifi District, with the last sightings occurring in the Arabuko Sokoke Forest in 1979. Differences in the settlement distribution, associated habitat loss and hunting preferences of the nine coastal tribes (Mijikenda) may explain why colobus have disappeared from the north coast, but persist in the south. 相似文献
8.
Peter J. Fashing Felix Mulindahabi Jean-Baptiste Gakima Michel Masozera Ian Mununura Andrew J. Plumptre Nga Nguyen 《International journal of primatology》2007,28(3):529-550
With group sizes sometimes >300 individuals, the Angolan black-and-white colobus (Colobus angolensis ruwenzorii) population
in Nyungwe Forest, Rwanda is an intriguing exception to the tendency for folivores to live in smaller groups than expected
relative to body size. Researchers have hypothesized that the unusually high quality of foliage at Nyungwe allows colobus
there to avoid intragroup feeding competition, releasing constraints on the formation of large groups (Fimbel et al., 2001). We collected data on the activity and ranging patterns of a >300-member Nyungwe colobus group and compared our results
to those from smaller groups in other black-and-white colobus (Colobus spp.) populations. Colobus at Nyungwe spent far more
time feeding and moving (62%) and far less time resting (32%) than black-and-white colobus at any other site. The annual home
range of the Nyungwe colobus was also many times larger (95% minimum convex polygon: 20.7 km
2
; 95% fixed kernel: 24.4 km
2
) than those for other populations. We terminated our research after the group engaged in an unprecedented migration among
black-and-white colobus by moving 13 km south of their former range. Our results suggest that intragroup scramble competition
may be more intense than originally believed within the large colobus groups at Nyungwe and that long periods of resource
renewal may be necessary after a large colobus group passes through an area, thereby potentially helping to explain their
wide ranging patterns. We discuss the socioecological convergence between the Nyungwe colobus and Chinese snub-nosed monkeys
(Rhinopithecus spp.) and suggest directions for future research on the unique black-and-white colobus population at Nyungwe.
相似文献
Peter J. FashingEmail: |
9.
Taxonomy and phylogeny of black-and-white colobus monkeys. Inferences from an analysis of loud call variation 总被引:1,自引:0,他引:1
Field recordings of male loud calls (or roars) from each major form of black-and-white colobus monkey have been analyzed spectrographically, and features of tempo and pitch measured. Considered together with data on cranial dimensions, coat pattern, and geographical distribution, the results of this analysis suggest that there are five species of black-and-white colobus: Colobus angolensis, C. guereza, C. polykomos, C. satanas, and C. vellerosus. C. guereza and C. vellerosus may have differentiated most recently during a major arid event prior to the last Pleistocene glacial maximum; they have an identical low-pitched roar which we consider to be a shared, derived character. The other species, of which C. satanas has the most distinct roar, may belong to older lineages. 相似文献
10.
Tuguo Tateoka 《Journal of plant research》1978,91(3):141-171
Relationships amongCalamagrostis longiseta var.longiseta, C.l. var.longe-aristata andC. fauriei, which are principally at the 2n=28 chromosome level, were studied mainly on the basis of population samples. The populations
comprised (1) “pure” populations of each ofC.l. longiseta, C.l. longe-aristata andC. fauriei and (2) populations showing a gradation fromC.l. longiseta toC. fauriei via the intermediateC.l. longearistata and fromC.l. longiseta toC.l. longe-aristata. Hybridization betweenC.l. longiseta andC. fauriei was estimated to be ultimately related to the geneses of the population structures detected, and it was concluded thatC.l. longe-aristata must be of hybrid origin betweenC.l. longiseta andC. fauriei. Populations showing a gradation fromC.l. longiseta toC.l. longe-aristata were regarded to have been brought about by the extinction ofC. fauriei from the hybridizing population coupled with the change of environments and also by the secondary contact betweenC.l. longiseta and plants ofC.l. longe-aristata migrating from the area that produced it. No significant reduction of pollen fertility and seed productivity was found inC.l. longe-aristata. Based on the results of population analyses, the delimitation of the taxa concerned was made clearer. The examination of
herbarium specimens showed that the range ofC.l. longe-aristata considerably exceeds the overlapping area of the present ranges ofC.l. longiseta andC. fauriei. The three taxa were deviated ecologically, and “pure” populations ofC.l. longe-aristata were found on several damp subalpine fields in central and northern Honshu that seemed to represent the most suitable niche
for this taxon. It was estimated thatC.l. longe-aristata would evolve into a new good species if the future organism-environment interactions are favorable for it. 相似文献
11.
The two West African black-and-white colobus taxa,Colobus polykomos andC. vellerosus, are distinct species. A supposedly intermediate subspecies,C. polykomos dollmani, is actually a hybrid swarm, in whichC. vellerosus genes greatly predominate. We propose a hypothesis to explain this situation. 相似文献
12.
V. Labeyrie 《BioControl》1961,6(4):257-263
Summary The layings ofCassida deflorata
Suffr. are parasited in southern France byMymaridae (Anaphoidea sp. andFulmekiella ovata
soyka),Trichogrammatidae (Monorthochaeta nigra
Blood.) andEulophidae (Foersterella flavipes
Foerst. andTetrastichus rhosaces
Walk.).
In the Alpes-Maritimes, two successive generations ofMymaridae andTrichogrammatidae seem to attack the layings ofC. deflorata.
In Corsica, parasitism byMymaridae andF. flavipes is very frequent and may be the essential regulating factor of the populations ofCassida.
In the other regions that have been studied, although the large number ofCassida imagos appearing in spring show that mortality during the aestivation and hibernation is not the primary factor, it does
not seem that the limitation of the populations is essentially caused by the activity of oophagous insects.
相似文献
13.
Masazumi Mitani 《Primates; journal of primatology》1990,31(4):625-634
Brief results of a survey are reported for the primate fauna in south-eastern Cameroon and northern Congo. The survey was
carried over the period from October 1988 to January 1989. I confirmed the occurrence ofMandrillus sphinx in the south-eastern part of Cameroon, viz. the south bank of the Dja river, the occurrence ofCercocebus albigena in almost all the survey areas, the occurrence ofCercopithecus cephus, C. nictitans, C. pogonias, andGorilla g. gorilla throughout the areas, and the occurrence ofCercopithecus neglectus andColobus badius near Bomassa, 70 km north of Ouesso, in Congo. I also confirmedColobus polykomos satanas in some parts of Cameroon, but this species is declining. Local people provided information onCercocebus galeritus agilis, Colobus guereza, andPan troglodytes in almost all the areas, in some of which I confirmed the animals directly. They also provided information aboutCercocebus torquatus on the north bank of the Dja river in Cameroon andMiopithecus talapoin in Sembe in Congo, although I could not confirm these species myself. Human activities had begun reducing the populations
of the above primates, particularly those ofMandrillus sphinx, Colobus polykomos satanas, andGorilla g. gorilla, in south-eastern Cameroon and in northern Congo despite the low density of the human populations. 相似文献
14.
M. Mei 《Insectes Sociaux》1992,39(2):145-156
Summary An up-to-date synthesis is presented of the available faunistic and biological data concerning the Italian species belonging to the socially parasitic ant generaEpimyrma Emery andChalepoxenus Menozzi.The first known populations ofE. corsica (Emery) andE. stumperi (Kutter) in Italy were discovered in the Lucretili mountains (Latium) and in Alto Adige, the former species being previously recorded only in Corsica and Dalmatia (Yugoslavia), the latter in the French and Swiss Alps.The first records ofE. ravouxi (André),E. kraussei (Emery) andC. muellerianus (Finzi) in central Italy are presented. Since no species of either genera has ever been collected in Italy in the area between the Po valley and Calabria, these new records are of great interest.Maps, showing the currently known distribution of each taxon in Italy, are provided. 相似文献
15.
Summary Three sympatric aphid species of European origin (Euceraphis betulae (Koch),Callipterinella calliptera (Hartig) andBetulaphis brevipilosa Börner) feed onBetula pendula Roth in northern California. The component species of this guild partition resources by plant part, feeding sites within leaves and leaf phenological state. Overall niche overlap between species reached a maximum of 49.9% betweenB. brevipilosa andC. calliptera. Co-occurence ofE. betulae with both other species on leaves was random while co-occurrence ofC. calliptera andB. brevipilosa was aggregated. Morphological features (stylet length and body weight) act to mediate niche organization within this guild.California populations ofE. betulae andB. brevipilosa appear to utilize resources in a fashion similar to endemic Danish populations. Whereas DanishC. calliptera usually feed inside leaves silked together by spiders or Lepidoptera,C. calliptera in California also commonly feed on exposed leaf surfaces. This species, which has thus expanded its endemic niche, occupies the most generalized niche of the three species studied. 相似文献
16.
Isabella A. Abbott 《Journal of phycology》1967,3(3):139-149
Pacific coast species of the red algae Halymenia and Cryptonemia are described Of the 8 previously reported species of Halymenia 3 (H. abyssicola Dawson, H. megaspore Dawson, H refugiensis Dawson) hive been placed in synonymy with other species. Halymenia hollenbergii from southern California is described as new; H cocinea is transferred from Schizymenia (and includes Aeodes gardneri Kylin) and H. templetonii is a transfer from Weeksia. Five species of Cryptonemia are described; one of them, C. taylorii from the Revillagigedo Archipelago, as new. Wider distribution ranges are given for the remaining species, C. ovalifolia, C. obovata, C. bore alis and C. angustata. Keys to genera of the west coast Cryptonemiaceae and to the species of Halymenia and Crypronemia are provided. 相似文献
17.
M L Eberhard M N Njenga A J DaSilva D Owino E K Nace K Y Won J M Mwenda 《The Journal of parasitology》2001,87(6):1394-1397
From March 1999 through August 2000, 511 stool samples collected from 11 different primate species in 10 geographically distinct locations in Kenya, East Africa, were screened for the presence of Cyclospora spp. oocysts. Positive samples (43/102, 42%) were identified in vervet monkeys (Cercopithecus aethiops) in 4 of 4 locations; 19/206 (9%) in yellow and olive baboons (Papio cynocephalus, P. anubis, respectively) in 5 of 5 locations; and 19/76 (25%) in black and white colobus monkeys (Colobus angolensis, C. guereza, respectively) from 2 of 3 locations. DNA sequences obtained from 18 S rRNA coding regions from respective subsets of these positive samples were typed as Cyclospora cercopitheci (samples from Cercopithecus aethiops). Cyclospora papionis (samples from Papio cynocephalus and P. anubis), and Cyclospora colobi (samples from Colobus angolensis and C. guereza). Cyclospora oocysts were not detected in samples collected from patas, highland sykes, lowland sykes, blue sykes, DeBrazza, or red-tailed monkeys. A coded map showing the geographic location of the collected samples is given. Stool samples from 1 troop of vervet monkeys were collected over a 12-mo period. Positive samples ranged between 21 and 63%. These results suggest that there is no strongly marked seasonality evident in Cyclospora infection in monkeys as has been noted in human infection. This is further confirmed by the recovery of positive samples collected from vervet monkeys, baboons, and colobus monkeys at all times of the year during this survey. This absence of seasonality in infection is especially notable because of the extreme weather patterns typical of Kenya, where marked rainy and dry seasons occur. A second noteworthy observation is that the striking host specificity of the Cyclospora species initially described was confirmed in this survey. Baboons were only infected with C. papionis, vervet monkeys with C. cercopitheci, and colobus monkeys with C. colobi, despite geographic overlaps of both the monkey and parasite species and wide geographic distribution of each parasite and monkey host. 相似文献
18.
Diets of two sympatric colobines in Zaire: More evidence on seed-eating in forests on poor soils 总被引:2,自引:0,他引:2
Recent studies have shown that the so- called folivorous African colobines eat a significant amount of seeds. There is disagreement
as to whether seed-eating is due to the poor quality of tree foliage, due in turn to poor soils, or to the fact that seeds
are a normal part of colobine diets. To test these hypotheses, we studied feeding of red colobus monkeys, Colobus badius tholloni,and black-and-white colobus monkeys, Colobus angolensis angolensis,in a tropical rain forest of Central Zaire (Salonga National Park). We conducted studies on soil properties, vegetation composition,
and the availability and chemical contents of food plants simultaneously. Soils were very acid, with a high percentage of
sand, very low cation exchange capacity, and very low exchangeable bases. The forest was dominated by legumes (45.6% of trees),
among which the Caesalpinioideae were the best represented (85%). C. badiusfed mostly on leaves (61%) and seeds (33%), legumes making up 65% of their diet. C. angolensisfed mostly on seeds (50%) and leaves (27%); 39% of their diet came from legumes. The two species tended to select items richer
in crude protein or lipids or both. Total phenolics and condensed tannins were abundant in the foliage and seeds but were
poor predictors of colobine choice of food. Intersite comparisons show that colobines in Zaire ate a higher proportion of
seeds than all other related species so far studied in Africa and that the Salonga forest had among the poorest soils and
harbored the highest percentage of Caesalpinioideae. Our results confirm that seed- eating is more common among colobines
living in areas where soils are poor. They strongly suggest that this link is mediated through forest composition, especially
the abundance of legumes, and that the development of seed- eating results both from the high availability of nutrient-rich
seeds and from the poor quality of mature tree foliage. 相似文献
19.
20.
Seven species ofCatapyrenium and one ofPlacidiopsis are reported from Greenland. Five taxa, viz.Catapyrenium michelii, C. norvegicum, C. squamulosum, C. waltheri andPlacidiopsis pseudocinerea are new to the area. Taxonomy, distribution and ecology are briefly discussed. A key to species and distribution maps are presented.Catapyrenium norvegicum is described as new. 相似文献