云南大理苍山西坡红瘰疣螈身体状况与繁殖时间研究

Body Status and Breeding Time of Tylototriton shanjing in West Slope of Cangshan Mountain,Dali,Yunnan

2019年6—7月,采用样线法对云南省大理白族自治州苍山西坡红瘰疣螈 Tylototriton shanjing 的种群数量、繁殖时间和个体身体状况进行调查,并对红瘰疣螈两性个体的繁殖时间,不同繁殖时段个体体质量、头体长、肥满度、重长比进行了分析。共观察到红瘰疣螈个体664只,其中雄性410只,雌性254只,整体性比偏雄,雄性个体的比例由繁殖前期的69%逐渐降至后期的49%。雌性个体体质量、头体长和肥满度在不同繁殖时段的差异有统计学意义,繁殖前期雌性个体大于繁殖后期的个体;除头体长和体质量外,雄性个体肥满度和重长比在不同繁殖时段的差异均无统计学意义。繁殖后期,雌雄两性红瘰疣螈小个体的比例均增加,体质量小于5 g,头体长小于50 mm的雄性个体比例由0逐渐增加到13.16%和10.53%;体质量小于10 g,头体长小于60 mm的雌性个体比例由0逐渐增加到10.26%和7.69%,显示两性个体中的较小个体参与繁殖时间均较晚。较小个体身体状况相对较差,运动能力、繁殖潜力和配偶竞争等都不具优势,可能采用了较晚繁殖的繁殖策略。

From June to July 2019,the population number,reproduction time and body condition of red knobby newt(Tylototriton shanjing)were investigated in the west slope of Cangshan Mountain,Yunnan Province,and the body mass,snout-vent length,relative fatness and ratio of body mass to snout-vent length of individuals in different reproductive periods were analyzed.Six hundred and sixty-four individuals,including 410 males and 254 females,were observed,and some morphological characters of the newts were measured in the 2 months of breeding season.The overall sex ratio was male biased.The proportion of males decreased gradually from 69%at the early breeding stage to 49%at the later stage.Based on the statistics of body mass,body size and relative fatness,the female individuals showed significant differences in body mass,snout-vent length,and relative fatness at different breeding stages.The body mass,snout-vent length and relative fatness of female individuals at early breeding stage were significantly larger than those at the later stage.Whereas the males did not show any significant difference in body condition index and ratio of body mass to snout-vent length except for snout-vent length and body mass.In both sexes,the proportion of small-size individuals increased during the late breeding stage.The proportion of male individuals with body mass less than 5 g and snout-vent length less than 50 mm increased gradually from 0 to 13.16%and 10.53%,and the proportion of female individuals with body mass less than 10 g and snout-vent length less than 60 mm gradually increased from 0 to 10.26%and 7.69%,respectively,indicating that the smaller individuals of both sexes participated in reproduction later.The body status of the smaller individuals was relatively poor,and they had no advantages in movement,fecundity and local mate competition,etc.,they might adopt the reproductive strategy of later reproduction.