Effect of the Nest Environment on Survival by Embryonic and Neonatal Turtles

巢穴环境对胚胎和新生龟生存的影响

• 批准号: 9305875
• 负责人: Gary Packard
• 金额: $ 9.4万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-15 至 1997-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9305875&HistoricalAwards=false
• 关键词: Effect; Nest; Environment; Survival; Embryonic

9305875 Packard Embryonic turtles survive to hatching in some nests but not in others. Moreover, hatchlings from some of the successful nests are large and robust whereas neonates from other successful nests are small and weakly. Why does survival by embryos vary? Why do hatchlings differ so much in size and vigor? Does the variation in vigor of hatchlings affect their ability to survive once they have emerged from the nest cavity? Research outlined in this proposal first will test the hypothesis that survival by embryonic turtles is affected by the physical environment in their nests (as well as by maternity). The contents of natural nests of both snapping turtles (Chelydra serpentina) and painted turtles (Chrysemys picta) will be manipulated so that effects of the environment on hatching success can be clearly distinguished from genetic and nongenetic effects related to maternity. The physical environment will be measured in these same nests so that strong inferences can be made concerning the specific causes of embryonic mortality. The program next will test the hypothesis that substantial variation in size and vigor of hatchlings is induced by the environment during incubation, and that this environmentally-induced variation affects the survival by turtles during the neonatal period. The program of study will document critical links between the environment encountered by developing embryos, survival by embryos to hatching, phenotypic variation in hatchlings, and survival by hatchlings during the neonatal period. The findings consequently will have important bearing on conservation programs that entail captive propagation and "head- starting" for several kinds of sea turtles. ***

小行星9305875 胚胎龟在一些巢中存活到孵化，但在另一些巢中则不然。 此外，孵化的一些成功的巢是大而强大的，而新生儿从其他成功的巢是小而弱。 为什么胚胎的存活率不同？ 为什么刚孵化出来的小海龟在大小和活力上差别如此之大？ 幼体的活力变化是否会影响它们从巢腔中出来后的生存能力？ 这项提案中概述的研究首先将测试一个假设，即胚胎海龟的生存受到巢穴中的物理环境（以及母性）的影响。 的内容的天然巢穴的鳄龟（Chelydra serpentina）和彩绘龟（Ammemys picta）将被操纵，使孵化成功的环境的影响，可以清楚地区分与母性有关的遗传和非遗传效应。 将在这些相同的巢中测量物理环境，以便可以对胚胎死亡的具体原因进行强有力的推断。 该计划接下来将测试这样一个假设，即孵化期间环境会引起幼龟大小和活力的显著变化，并且这种环境引起的变化会影响新生期海龟的生存。 该研究计划将记录发育胚胎所遇到的环境，胚胎存活到孵化，孵化后代的表型变异以及新生儿时期孵化后代的存活之间的关键联系。 因此，这些发现将对保护计划产生重要影响，这些计划需要圈养繁殖和几种海龟的“领先优势”。 ***