| The conservation of endangered species constitutes the critical component and priority mission of both wildlife management and biodiversity conservation. On site conservation and off site conservation are the two dominant species conservation approaches. The objective is to restore and maintain the natural populations. Ultimately the ecosystem is revived and conserved through conservation of the key species, and through preservation and maintenance of biodiversity. The success or failure of the conservation of endangered species relies on both the genetic diversity and population viability. Needless to say, this is also pertinent to establishment and management of a captive breeding population, reintroduction of the population, habitat management, preparation and implementation of the protected area planning and conservation action plan.The rare bird species, Tragopan caboti, endemic to China, is among the critically endangered species globally. It is distributed in only such provinces (regions) as Zhejiang, Fujiang, Jiangxi, Hunan, Guangdong and Guangxi. Some 4,000 individuals of this species are estimated to be surviving in their natural habitat, however the population is seriously fragmented and isolated. So far upwards of 30 nature reserves, in the main distribution area of the species, have been established and on site conservation has been carried out. In addition, one captive breeding population each has been established in Hunan and Beijing respectively and initial headway made on off site conservation. So far there has been little documentation of the genetic diversity and population viability analyses in relation to Tragopan caboti, either at home or abroad.1. The key technique for establishment of a captive breeding population of Tragopan caboti was studied. This research distilled expertise for introduction, domestication, disease control and other management in relation to Tragopan coboti captive breeding population. Finally a set of technical standards and parameters was established. An inventory of the parasites infesting introduced natural individuals of Tragopan caboti demonstrated that dominant parasites included Coccidiosis and Histomoniasis and effective control measures against these diseases were gleaned, which provided experience for the introduction aimed at establishment of a captive breeding population, disease quarantine and control as well. Tests were made to prevent and control five dangerous and seven common diseases. The results indicated that the diseases infesting Tragopan caboti or poultry shared common grounds. Cross infestations were found between poultry and Tragopan caboti, which laid scientific foundation for effective cure approaches for such diseases as Newcastle Disease, Avian Pasteurella and Escherichia coli. Particularly a rapid test method, using AGID to testify Newcastle Disease, was found. The disease, caused by the bacterium, Botulism was cured for the first time, which filled the gap of disease control for both captive and natural populations of Tragopan caboti.2. The breeding behavior was studied. Taking into consideration the behavior characteristics and demands of Tragopan caboti, research on the reproduction pattern of the ecological population was conducted. The comparison between group-rearing under ecological conditions to couple-rearing in captive conditions showed that there was a close relationship between reproduction rate and size of the population, living space, vegetation and concealment. Generally group-rearing, larger living space, and abundant vegetation could improve the reproduction rate. Group-rearing can increase egg-laying by 50% and the average of individual egg-laying marked 8.5 eggs a-1, the fertilization ratio increased by 32.3%, reaching 82.6%. Nutrition elements and forage formula for different growth periods were screened for Tragopan caboti, through nutrition analysis and comparison researches. In addition nutrition formula, in light of bionomics of the birds, on the day-age basis during the nestling rearing periods, and regular immunity were adopted. As a result the survival rate of the nestlings peaked at 91.3%.3. The reproduction regularity of Tragopan caboti was understood. Consecutive research for seven years on reproduction showed that the estrus of the female was markedly earlier than that of the male. The discrepancy in the estrus led to a drop in fecundation, which was considered as the underlying cause of the low reproduction rate and status of being endangered. A study on artificial incubation indicated that the Tragopan caboti demonstrated strong emergency response and the number of eggs laid was three times of that under natural conditions. Under natural conditions the annual average of eggs laid per female was three eggs whilst under artificial condition it was 8.5 eggs. The initial egg-laying commenced in earlier March under the latter condition. For instance, up to 19 eggs were produced by one female from the cage H2 in 2002,6 times of the average under natural conditions, which implied that the survival potential of this species was adequately high. In addition, the research also showed that some 25%-30% of the reproductive individuals were able to produce fertilized eggs in the second year and culminated in nestlings. However the male individuals at the same age could not successfully produce progeny. This illustrated that the male sex maturation lagged behind the female. 4. Different mate combination patterns were examined. Such mate patterns as one male coupling one female, one male matching multi-female, and multi-male matching multi-female were tried and the results indicated that the last pattern was the best. Moreover, out of various options of multi-male matching multi-female, the option of the males outnumbering the females was the best, which generated 83.1% fecundation rate and 89.2% incubation rate, clearly higher than the other options. This implies that this species developed the ecological strategy of K-Selection. In other words, improving the number of viable population through larger proportion of males, and controlling the abundance of the entire population and securing the adequate gene heterozigosity of the population.5. The artificial incubation technique and relevant indicators were developed. The incubation rate reached 89.2%, at a critical temperature of 37.5?, humidity of 65-67%, nestling emerging temperature of 36.5?and emerging humidity of 65-100%. These development conditions differed greatly from that for the domestic chickens, Phasianus colchicus, Chrysolophus pictus, and Syrmaticus ellioti reared in the reproduction site, with lower critical temperature and emerging temperatures but higher humidity.6. Randomly amplified polymorphic DNA markers and Microsatellites analysis were applied to analyze the genetic diversity of the different group/populations, i.e. wild group, the captive breeding four groupsfirst filial generation.40 primers were used,and 10 loci were tested. The results reveal that captive breeding decreases the genetic diversity of the species. And these results also imply it is not proper to conserve species by captive breeding.7. The genetic similarity and distances of the different groups were analyzed by RAPD and SSR testing. The genetic similarity and distance for every two groups and individuals were calculated with a matrix of RAPD and SSR based. However, the genetic similarity declined gradually for wild and captive breeding groups, and genetic distance increased with each generation. The genetic variation that occurred distinctly increased with each generation for captive breeding groups.8. The genetic variation of wild and captive breeding groups was studied RAPD-based. The analysis results also showed that average heterozygosity(Hpop) by population was 0.1073 for whole groups, average heterozygosity (Hsp) by species was 0.1752, the average genetic variability by species (HPOP/Hsp) was 0.7331, and average genetic variability by population ((Hsp-Hpop)/Hsp) was 0.2668. This indicated that the most genetic variation was from groups, only 26.7% genetic variability was tested in different individuals. 9. Hardy-Weinberg genetic equilibrium was used to test genetic diversity for all the groups of Tragaopan caboti through ten loci, analysis revealed that heterozygosity excess and deficiency respectively in wild, first captive breeding groups and third, fourth, fifith captive breeding groups. Moreover, analysis detected that first captive breeding groups and third, fourth, fifith captive breeding group showed a remarkable genetic disequilibrium and heterozygosity distinct deficiency at loci MCW330,?MCW29?MCW34.10. The population viability of the captive breeding group of Tragopan caboti was examined with the software Vortex 9.51. About 100 simulations for 50 years were tested, on the basis of data collected for eight years in a row. Considering the human factor, inbreeding stress and impact of the environment variance, with assumption carrying capacity marking 500±50 (SD=0.1), under the condition of no harvesting, the determined rate of natural increase R was 0.113 birds (SD= 0.238, PE=0.1). Before reaching the carrying capacity ceiling, the stochastic increase rate was 0.053 (SD=0.238, PE=0.1) and the mean increase rate 0.0458 (SE=0.0035; SD= 0.2401), under the integrated impact of all factors. The ultimate population size (including existing and extinct populations) averaged 348.35 (SE=14.57, SD=145.72) or 362.56 (SE=13.23, SD=129.67), removing extinct populations. The length of the population generation lasted 4.85 years. In other words, the population gene would be reshuffled once every 4.85 years. The female's reshuffle took 4.16 years whilst the male's 5.45 years. The finite rate of increase (?) was 1.12 (time/per year) and net increase (RO) 1.604. The number of the adult males was 1.259 times that of the adult females. At least one extinction occurred within 25 modelings and four extinctions happened within 50 years.11. The sensitivity of the lethal factors was analyzed. Specifically such factors affecting the population fluctuation factors as the reproduction rate, mortality, sex ratio, catastrophes, environmental carrying capacity, initial population size, and metapopulation effect were examined to understand their sensitivity. As a result, the key factors affecting the survival of the population were identified after analysis. The findings suggested that the reproduction rate of the females, chick mortality, carrying capacity, initial population size and the subpopulation size were the key lethal factors. The impact of the lethal loci on the small population was obvious. In addition the minimum viability population (MVP), the size and sex ratio of initial population for reintroduction, and parameters for key techniques were determined.12. The population features of Tragopan caboti were examined. The analysis of population viability and captive breeding showed that Tragopan caboti was very sensitive to environmental variance. Thus the metapopulation consisting of multi-subpopulations was conducive to maintaining relatively high genetic diversity and offseting the impact of environmental variance. More, effective population can be augmented through the strategy of raising the male proportion. This attests to the feature of metapopulation under natural conditions, a contest strategy adopted by this species under the precondition of retaining genetic diversity. Given the carrying capacity at 100,200,300,400, and 500 birds (SD=0.1), there existed a high correspondence between the number (N) of the subpopulation and the regression equation, i.e. N=5.6390+0.813991K, with R=0.9997 and RR=0.9994.13. Strategies for on site conservation and off site conservation, pertinent to the Tragopan caboti, were provided. Taking into consideration the quantity of the Tragopan caboti, genetic diversity, population viability, social economic conditions and the requirements of the species conservation, the approach of combining both on site conservation and off site conservation should be adopted. Also the established management techniques of captive breeding population should be applied and captive breeding populations augmented. At the same time, genetic diversity should be preserved. Particularly restoration of the natural population at more sites should be achieved to maintain the adequate quantity of natural population and survival probability so as to overcome the impact brought by environment factors, particularly the events of catastrophic proportion leading to population extinction. |
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