Delayed sexual maturity and demographics of blanding's turtles (Emydoidea blandingii): implications for conservation and management of long-lived organisms
Delayed sexual maturity and demographics of blanding's turtles (Emydoidea blandingii): implications for conservation and management of long-lived organisms
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布兰丁龟（Emydoidea blandingii）性成熟延迟和人口统计：对长寿生物体保护和管理的影响
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
R. C. V. L. Sels
中科院分区：
文献类型：
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作者：
J. Congdon;A. Dunham;R. C. V. L. Sels
摘要：一项在过去37年中有27年对布朗德海龟进行的研究提供了足够的人口统计学数据，以检验生活史特征如何限制长寿生物的种群反应。8个独立估计的成人年存活率超过93%。巢存活率每年在0.0%~63%之间变化，1976~1984年的平均值为44%，1985~1991年的平均值为3.3%。招募青少年和成年人足以取代估计在研究期间死亡的个人。种群生命表的结果是队列世代时间为37年，1至13岁的幼虫需要72%的年存活率才能维持稳定的种群。种群稳定性对成虫或幼虫存活率的变化最敏感，对性成熟年龄、巢存活率或繁殖力的变化不太敏感。本研究的结果表明，长寿生物体的生活史特征由共同进化的特征组成，这些特征导致种群对长期干扰的反应能力受到严重限制。成功的长寿生物管理和保护计划将是那些认识到对所有生命阶段的保护是必要的。在缺乏降低年龄较大的青少年和成年人死亡率的计划的情况下，例如提前启动或仅保护筑巢地点等计划，似乎不足以拯救海龟和一些乌龟等长寿生物。对已经减少的长寿生物种群进行可持续收获的概念似乎是一个矛盾的修饰法。
Abstract: A study of Blanding's turtles conducted during 27 of the last 37 years provided demographic data sufficient to examine how life-history characteristics may constrain population responses of long-lived organisms. Eight independent estimates of annual adult survivorship exceeded 93%. Nest survival was variable and ranged from 0.0 to 63% annually, with a mean of 44% from 1976 to 1984 and 3.3% from 1985 to 1991. Recruitment of juveniles and adults was sufficient to replace individuals estimated to have died during the study. A life table for the population resulted in a cohort generation time of 37 years and required a 72% annual survivorship of juveniles between 1 and 13 years of age to maintain a stable population. Population stability was most sensitive to changes in adult or juvenile survival and less sensitive to changes in age at sexual maturity, nest survival, or fecundity. The results from the present study indicate that life-history traits of long-lived organisms consist of co-evolved traits that result in severe constraints on the ability of populations to respond to chronic disturbances. Successful management and conservation programs for long-lived organisms will be those that recognize that protection of all life stages is necessary. Programs such as headstarting or protection only of nesting sites, in the absence of programs to reduce mortality of older juveniles and adults, appear to be less than adequate to save long-lived organisms such as sea turtles and some tortoises. The concept of sustainable harvest of already-reduced populations of long-lived organisms appears to be an oxymoron.