Study On The Breeding Ecology And Early Embryonic Development Of Odorrana Schmackeri In Nanzhao County Of Henan Province

Odorrana schmackeri (Anura,Ranidae,Odorrana), an endemic species to China,widelydistributed in Henan,Shaanxi,Gansu,Chongqing,Sichuan,Guizhou,Anhui,Hubei,Hunan,Jiangsu,Jiangxi,Guangdong,Guangxi,etc. The reseach currently has mainly focused on the morphology andclassification,karyotype,histology and phylogenetic aspects,etc. The basic knowledge of breeding ecologyis very poor,while the early embryonic development research is still a blank. The aim of this study was tomaster and understand the breeding ecology and behavior of Odorrana schmackeri,and to explore theecology adaptation in the early embryonic development of the species.In July to November of2010and April to August of2011,we did the research for5times withinthe range of200m (111°59.182′～111°59.477′E,33°30.743′～33°30.872′N) of Pine river section ofNanzhao county in Henan province. Tied colored cotton to knee joint,we estimated the number ofOdorrana schmackeri by repeat mark-recapture method; to research the breeding season and matingsystem,we used continuous observation and Pearson correlation coefficient to estimate the intensity of thesize-assortative mating;using Spearman and Pearson correlation coefficient,we analysed the correlationbetween the body length,weight and the clutch size,egg size to study the reproductive investment;thoughsimulation experiment and independent-t-test,we studied the male-male competition and sexualselection;according to Gosner(1960),we studied the early embryonic development through interval andcontinuous observation.The results showed that:1.The number of Odorrana schmackeri was between82～178in2010-2011.2.Spawning activities of the frogs occured from late July to early August, lasting about one week,which belonged to explosive breeding. The sex ratio of males to females was2.61:1in2010, while in2011,it was2.88:1, both of which was male-biased. Significant size-assortative mating was not found in thepopulation.3.There was no significant negetive correlation between female body length and clutchsize(r=-0.09,p=0.86>0.05,n=6),while for female body length and egg size,there was no significant positivecorrelation(r=0.72,p=0.11>0.05,n=6). There was aslo no sigificant postive correlation between female body weight and clutch size(r=0.06,p=0.92>0.05,n=6),and the same condition occured between female bodyweight and egg size(r=0.24, p=0.64>0.05,n=6).There was no significant negetive correlation between eggsize and clutch size(r=-0.24,p=0.64>0.05,n=6).4.Male-male competition was present in this population. The competition behavior of the malesincluded calling,fighting,biting,collision,and so on.5.The whole process of the early embryonic development may be devided into25stages. Theembryo of the species hatched at muscular response stage,which was earlier than most of other amphibians.The early embryonic development of Odorrana schmackeri took324.13hours(about13.5days) under thewater temperature of20～26℃.