Study On The Spatial Occupancy Of 11 Common Amphibians In Guangxi

The amphibians investigation in four areas (Dayao Mountain, Mao'er Mountain,Nonggang and Beiliu) of Guangxi was conducted by using the line transect method and the artificial shelter method in 2014-2016. The data results show that 42 amphibian species, belonging to 31 genera, 10 families and 3 orders, was found in 2014. 11 species of Frog family, 8 species of Tree frog family and 6 Microhylidae species were accounting for 26.19%,19.05% and 14.29% respectively of the total amphibian species observed. 44 amphibian species, belonging to 34 genera, 10 families and 3 orders, was found in 2015. Tree frog family, Frog family and Microhylidae species were accounting for 25.00%, 20.45% and 13.64% respectively of the total number of amphibian species observed. 45 amphibian species, belonging to 31 genera, 11 families and 3 orders, was found in 2016. Frog family, Tree frog family and Microhylidae species were accounting for 20.00%, 20.00% and 13.33%respectively of the total number of amphibian species observed. According to the survey statistics, Frog family, Tree frog family and Microhylidae are the dominant families with most species in the four areas of Guangxi, In this paper, site occupancy analysis of 11 common amphibian species (Duttaphrynus melanostictus,Boulengerana guentheri, Sylvirana latouchii, Fejervarya multistriata,Hoplobatrachus rugulosus,Quasipaa spinosa,Polypedates megacephalus,Microhyla pulchra, Microhyla butleri, Microhyla fissipes, Microhyla heymonsi) was conducted.The site occupancy analysis of the 11 amphibian species was conducted with the site-occupancy model in the PRESENCE program. The site occupancy probabilities and detection probabilities of 11 species in the April, June and August respectively were estimated by the single-season model. Then the site occupancy probabilities and detection probabilities of 11 species in 2014-2016 yearly were estimated by the multi-season model. Furthermore, this study introduced elevation and habitat types as the site-specific covariates and the temperature as a sampling-occasion covariate into the site-occupancy model, and it analyzed how the environmental factors influenced the distribution of amphibians. The results showed that the site occupancy rates of 11 species in the three period of April, June and August have had no significant seasonal change because the 11 species are also active in these seasons. The annual site occupancy rates of B.guentheri, H.rugulosus, P.megacephalus,M.pulchra and M.fissipes have presented a trend of decline from 2014 to 2016. However, the annual site occupancy rates of S.latouchii, F.multistriata and M.heymonsi have showed rising trend. According to the model weights calculated through the model selection,elevation has the highest model weights and then the habitat types. This illustrated that the elevation was likely the most important factor on the distribution of amphibians. And the habitat types probably may be correlated with the elevation.Both seasonal detection rates and the annual detection rates have heterogeneity indeed.And it was may be related to the weather conditions such as temperature, cloud cover,wind speed, precipitation, etc.Finally, in this study, the site occupancy model was evaluated by practicability of the model and the design of the survey program to make it more widely applied in amphibian monitoring and even other biodiversity surveying, and further to provide information for scientific protection and management of biodiversity.