Temporal patterns of three sympatric pheasant species in the Nanling Mountains: N-mixture modeling applied to detect abundance  

作　　者：Fasheng Zou Qiang Zhang Min Zhang Myung‑Bok Lee Xincai Wang Yuening Gong Changteng Yang 

机构地区：[1]Guangdong Key Laboratory of Animal Conservation and Resource Utilization,Guangdong Public Laboratory of Wild Animal Conservation and Utilization,Guangdong Institute of Applied Biological Resources,Guangzhou 510260,China [2]Guangdong Nanling National Nature Reserve,Ruyuan 512727,China

出　　处：《Avian Research》2019年第4期405-414,共10页鸟类学研究（英文版）

基　　金：supported by Guangdong Science and Technology Plan Project(2013B02031005);Guangdong Academy of Science(GDAS)Special Project of Science and Technology Development(2017GDASCX-0107,2018 GDASCX-0107);Guangdong Forestry Special Project(0877-16GZTP01D060,1210-1741YDZB0401);Special Fund of Guangdong Nature Reserve(RYCG12-14,GDHS15SGFX07060,Cabot’s Tragopan monitoring)

摘　　要：Background:The reliability of long-term population estimates is crucial for conservation and management purposes.Most previous studies assume that count indices are proportionally related to abundance;however,this assumption may not hold when detection varies spatially and temporally.We examined seasonal variations in abundance of three bird species(Cabot’s Tragopan Tragopan caboti,Silver Pheasant Lophura nycthemera,and Whitenecklaced Partridge Arborophila gingica) along an elevational gradient,using N-mixture models that take into account imperfect detection in our bird data.Methods:Camera-trapping was used to monitor temporal activity patterns of these species at Guangdong Nanling National Nature Reserve from December 2013 to November 2017(4 seasons per year).For abundance analysis(N-mixture modeling),we divided a year into 4 seasons,i.e.3 months per season,and performed the analysis by season.Elevation was incorporated into the N-mixture model as a covariate that may affect abundance.We compared the N-mixture model with a null model(no covariate model) and selected the better model based on AIC values to make an inference.Results:From 24 sampling sites,we obtained 6786 photographs of 8482 individuals of 44 bird species and 26 mammal species.Silver Pheasant was photographed much more frequently and showed higher temporal activity frequency than White-necklaced Partridge or Cabot’s Tragopan.Silver Pheasant was camera-captured most frequently in summer,and other two species in winters.All three species had two daytime activity peaks:between 6:00 a.m.and 10:00 a.m.,and between 5:00 p.m.and 7:00 p.m.,respectively.Our estimated abundance and detection probability from the N-mixture model were variable by season.In particular,all three species showed greater abundance in summer than in winter,and estimated abundance patterns of all three species were more similar with observed cameratrapping counts in summers.Moreover,in winter,elevation had a positive impact on abundance of Silver Pheasant and Cabot’s TragopanBackground:The reliability of long‑term population estimates is crucial for conservation and management purposes.Most previous studies assume that count indices are proportionally related to abundance;however,this assumption may not hold when detection varies spatially and temporally.We examined seasonal variations in abundance of three bird species(Cabot’s Tragopan Tragopan caboti,Silver Pheasant Lophura nycthemera,and Whitenecklaced Partridge Arborophila gingica)along an elevational gradient,using N‑mixture models that take into account imperfect detection in our bird data.Methods:Camera‑trapping was used to monitor temporal activity patterns of these species at Guangdong Nanling National Nature Reserve from December 2013 to November 2017(4 seasons per year).For abundance analysis(N‑mixture modeling),we divided a year into 4 seasons,i.e.3 months per season,and performed the analysis by season.Elevation was incorporated into the N‑mixture model as a covariate that may affect abundance.We compared the N‑mixture model with a null model(no covariate model)and selected the better model based on AIC values to make an inference.Results:From 24 sampling sites,we obtained 6786 photographs of 8482 individuals of 44 bird species and 26 mammal species.Silver Pheasant was photographed much more frequently and showed higher temporal activity frequency than White‑necklaced Partridge or Cabot’s Tragopan.Silver Pheasant was camera‑captured most frequently in summer,and other two species in winters.All three species had two daytime activity peaks:between 6:00 a.m.and 10:00 a.m.,and between 5:00 p.m.and 7:00 p.m.,respectively.Our estimated abundance and detection probability from the N‑mixture model were variable by season.In particular,all three species showed greater abundance in summer than in winter,and estimated abundance patterns of all three species were more similar with observed cameratrapping counts in summers.Moreover,in winter,elevation had a positive impact on abundance of Silver Pheasant and Ca

关 键 词：Abundance estimation CAMERA-TRAPPING Imperfect detectability Nanling Mountains Spatio-temporal distribution Sympatric distribution 

分 类 号：Q95[生物学—动物学]