Yang J.,Sichuan Agricultural University |
Yang J.,Chengdu Research Base of Giant Panda Breeding |
Zhang Z.,Chengdu Research Base of Giant Panda Breeding |
Shen F.,Chengdu Research Base of Giant Panda Breeding |
And 6 more authors.
Current Zoology | Year: 2011
Understanding present patterns of genetic diversity is critical in order to design effective conservation and management strategies for endangered species. Tangjiahe Nature Reserve (NR) is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tangjiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 individuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low F IS-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number (A), Allelic richness (AR) and mean expected heterozygosity (H E) for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort. © 2011 Current Zoology.
Zhang W.,Chengdu Research Base of Giant Panda Breeding |
Yie S.,Chengdu Research Base of Giant Panda Breeding |
Yue B.,Sichuan University |
Zhou J.,Southwest forestry University |
And 9 more authors.
PLoS ONE | Year: 2012
It has been recognized that other than habitat loss, degradation and fragmentation, the infection of the roundworm Baylisascaris schroederi (B. schroederi) is one of the major causes of death in wild giant pandas. However, the prevalence and intensity of the parasite infection has been inconsistently reported through a method that uses sedimentation-floatation followed by a microscope examination. This method fails to accurately determine infection because there are many bamboo residues and/or few B. schroederi eggs in the examined fecal samples. In the present study, we adopted a method that uses PCR and capillary electrophoresis combined with a single-strand conformation polymorphism analysis (PCR/CE-SSCP) to detect B. schroederi infection in wild giant pandas at a nature reserve, and compared it to the traditional microscope approach. The PCR specifically amplified a single band of 279-bp from both fecal samples and positive controls, which was confirmed by sequence analysis to correspond to the mitochondrial COII gene of B. schroederi. Moreover, it was demonstrated that the amount of genomic DNA was linearly correlated with the peak area of the CE-SSCP analysis. Thus, our adopted method can reliably detect the infectious prevalence and intensity of B. schroederi in wild giant pandas. The prevalence of B. schroederi was found to be 54% in the 91 fecal samples examined, and 48% in the fecal samples of 31 identified individual giant pandas. Infectious intensities of the 91 fecal samples were detected to range from 2.8 to 959.2 units/gram, and from 4.8 to 959.2 units/gram in the fecal samples of the 31 identified giant pandas. For comparison, by using the traditional microscope method, the prevalence of B. schroederi was found to be only 33% in the 91 fecal samples, 32% in the fecal samples of the 31 identified giant pandas, and no reliable infectious intensity was observed. © 2012 Zhang et al.
Guan T.,Beijing Normal University |
Guan T.,Mianyang Normal University |
Ge B.,Yancheng Teachers University |
Mcshea W.,Smithsonian Conservation Biology Institute |
And 5 more authors.
Acta Theriologica Sinica | Year: 2012
Knowledge of the home range of wildlife is the basis of effective conservation and management. We studied takin (Budorcas taxicolor tibetana) home range in spring with two widely applied methods using GIS related software, where we compared differences between the home range estimates with and without terrain information. All four takin (2♀2♂) were fixed with GPS radio collars and the data were obtained in the spring of 2007 and of 2008. The results showed home range size derived with terrain information (FKE95%=7.50±2.27, MCP=7.01±1.99) was significantly larger than that derived without topographic information (FKE95%=5.94±1.54, t=3.31, df=3, P=0.045, MCP=5.47±1.52, df=3, t=3.34, P=0.041). The difference between estimates based on 95% Fixed kernel home range and Minimum convex polygon home range were not significant regardless of including terrain information (t=0.612, df=3, P=0.584) or not (t=0.718, df=3, P=0.524). However, we also found significant differences of home range size between individuals (One way ANOVA, df=3, F=7.226, P=0.001). The post hoc test between individuals found significant differences between M1 and F1 (P=0.001), M1 and F2 (P=0.031), M1 and M2 (P=0.02), F1 and F2(P=0.044), whereas no significant difference was detected between M2 and F2 (P=0.221), M2 and F1 (P=0.598). We also tested the difference of the two methods on the results of spatial overlap between individuals, but no significant difference was detected. Researchers should select appropriate smooth parameters (h)/bandwidth, because different bandwidth may derive different conclusions of the degree of home range overlap, or even contradictory results.
Guan T.P.,Mianyang Normal University |
Ge B.M.,Yancheng Teachers University |
Chen L.M.,Tangjiahe National Nature Reserve |
You Z.Q.,Mianyang Normal University |
And 3 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2015
Migrant and resident are observed to return or stay within a specific range of habitat, close to or completely overlap with its original distribution area, known as habitat fidelity. In this study, we estimated takin seasonal and annual home range size and its fidelity between years by utilizing 9 GPS radio collars on adult takin(2006—2009). Results shown annual home range of takin was (MCP/ FKE)(15.01±2.92)km2 / (9.02±1.85) km2, suggesting individual home range varied among individuals and years. For each individual, we found variation of seasonal home range between years. Most of individuals shown similar pattern of seasonal home range variation, thus the largest home range always found in summer or spring. We extracted the centriods of seasonal / annual home range polygon and calculate its distance between years. We tried the distance between two centriods as one surrogate of home range fidelity. Besides, we considered the overlap ratio of home range between two consecutive years as the most important parameter of home range fidelity.Therefore, we found annual home range fidelity of certain season variation exist, especially for summer and autumn. Both ways of home range fidelity assessment produced similar results. © 2015, Ecological Society of China. All rights reserved.
Wen Z.,CAS Institute of Zoology |
Wen Z.,University of Chinese Academy of Sciences |
Wu Y.,CAS Institute of Zoology |
Wu Y.,University of Chinese Academy of Sciences |
And 6 more authors.
Biotropica | Year: 2014
Our understanding of geographic patterns of species diversity and the underlying mechanisms is increasing rapidly, whereas the temporal variation in these patterns remains poorly understood. We examined the seasonal species richness and species turnover patterns of non-volant small mammals along three subtropical elevational gradients in southwest China. Small mammal diversity was surveyed in two seasons (early wet season and late wet season) using a standardized sampling protocol. The comparison of species richness patterns between two seasons indicated a temporal component in magnitude and shape, with species richness at high elevations clearly increased during the late wet season. Species richness demonstrated weak correlations with modelled temperature and precipitation. The elevational pattern of species turnover measured by Chao-Sørenson similarity index also changed seasonally, even though the temporal pattern varied with scale. Species turnover between neighboring elevations at high elevations was slower in the late wet season. Meanwhile, there was an acceleration of species turnover along the whole range of the gradient. The seasonal change in species diversity patterns may be due to population-level increases in abundance and elevational migration, whereas seasonal variation in factors other than temperature and precipitation may play a greater role in driving seasonal diversity patterns. Our study strongly supports the seasonality in elevational patterns of small mammal diversity in subtropical montane forests. Thus it is recommended that subsequent field surveys consider temporal sampling replicate for elevational diversity studies. © 2014 The Association for Tropical Biology and Conservation.
Li Y.,China West Normal University |
Zhang Z.,China West Normal University |
Sun Y.,China West Normal University |
Chen L.,Tangjiahe National Nature Reserve |
And 2 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2012
Habitat selection among allied species is one of the key supports for niche theory in ecology. Line transects and systematic sampling was used to study habitat selection by Chevrier's field mouse and the South China field mouse from June to August 2009. The two species are sympatric in the Tangjiahe Nature Reserve, Qingchuan County, Sichuan Province, China. We compared habitat plots used by both mammals and control plots reflecting the environment at large to investigate their habitat use patterns. 140 plots were measured totally. Of which, 49 were used by Chevrier's field mouse, 41 were used by South China field mouse and the rest 50 were control plots. 21 environmental variables potentially influencing their habitat selection were measured. In univariate analysis, 16 variables were significantly different between plot groups, indicating the two mammals both have a distinct significant habitat preference. In addition, their selected habitats overlapped to some extent: they both preferred for habitats with gentle slopes, lower canopy height, significant fallen leaf ground coverage, a relatively higher proportion of open land, larger tree diameter at breast height, greater tree height, moderate shrub bamboo and herb density, and larger herb coverage when compared with the control plots. Significant differences in habitats selected indicated the two species have distinct habitat selection patterns. Chevrier's field mouse occurred more frequently in habitats with lower elevations (about 1400 m) and taller herbs (about 16-30 cm), while South China field mouse occurred in habitats with higher elevations (about 1900 m) and shorter herbs (<15 cm). Moreover, Chevrier's field mouse preferred for habitats characteristic of evergreen and deciduous mixed broad-leaved forests, a shorter distance to water sources (<50 m), vegetation in earlier successional stage (a small growth of trees) and shorter bamboo height(<1 m). South China field proved to be more of a generalist with no prominent selectivity for the above ecological factors. This indicated the former's habitat is more decentralized while Chevrier's field mouse's habitat is more centralized or its habitat use is more specialized. Stepwise discriminant function analysis showed the four variables of elevation, vegetation stage of succession, canopy, and herb height contributed more to habitat separation between the two small mammals than others. The higher discriminant function coefficients indicated the two species could coexist sympatrically. Habitat-use strategies are often cited as the means by which sympatric species avoid competition. Occupying separate microhabitats is common among sympatric species. It seemed that these two small mammals can coexist and evolve in the same region contributing to their temporal and spatial separation in habitat use. Since they have similar body sizes and breeding dates and share the same food sources, we hypothesize habitat separation between the two species may not have resulted from differences in physiological and ecological requirements, but from ecological or evolutionary adjustment to reduce interspecific competition. Based on our findings, different habitat management strategies should be adopted for the two species.
Pi H.Q.,China West Normal University |
Quan Q.M.,China West Normal University |
Gao H.,China West Normal University |
Li Y.X.,China West Normal University |
And 3 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2016
The anthesis, visitors, pollinators and their behaviors, nectar secretion, breeding system of Caragana sinica (Buchoz) Rehd were investigated in Sichuan Tangjiahe National Nature Reserve. The results showed that the flowering span of single flower and the population approximately lasted 5, 20 days for C. sinica (Buchoz) Rehd, respectively. Pollinator functional groups were consisited of Anthophora, Bombus, Aethopyga. According to comparing difffrent pollinators of visitation frequency and pollen deposition on stigmas, the Pyganthophora rubricus Dours and Aethopyga gouldiae were primary efficient pollinators, Bombus was secondary efficient pollinator, formicidae and Apis mellifera Linnaeus were main robbers. The largest amount of nectar secretion of bagged flowers occurred at around 16:00 in diurnal, and the maximum volume of nectar occurred in fifth day, along with anthesis; All of them with an increasing trend. There was a positive correlation between nectar secretion and visiting frequency. Detection of breeding system indicated that pollen-ovule ratio was about 3779±320.9. The most suitable time of stigma receptivity happened at 2-3day after flowering. In conclusion, C. sinica (Buchoz) Rehd needed pollinators and belong to melittophilae and ornithophilous cross-pollinated. © 2016, Ecological Society of China. All rights reserved.