Dissertational Improvement: Water and Energy Balance Constraints on the Nesting Ecology of Tropical Seabirds

论文改进：热带海鸟筑巢生态的水和能量平衡约束

• 批准号: 9321759
• 负责人: Robert Ricklefs
• 金额: --
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-03-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9321759&HistoricalAwards=false
• 关键词: Dissertational; Improvement; Water; Energy; Balance

9321759 Ricklefs Both energy and mass constraints are continually interacting to influence the ecology of organisms. No where is this more clearly demonstrated than in nesting tropical seabirds where there is strong selection to store energy for the incubation shift and also to maintain water balance in this hot, harsh, environment. In the Northwestern Hawaiian Islands, Wedge-tailed Shearwaters compete for nesting burrows, and those without burrows (44% of the population) must nest on the ground surface. If these sites have little protection from solar radiation, only 5-11% will produce chicks. In contrast to shearwaters, both Sooty Terns and Brown Noddies regularly nest in the open sun and 85% of the nests produce chicks. To better understand this disparity in ability to nest in a hot environment, the PI has constructed a conceptual model that links energy and material balances so that their interactions can be clearly understood. Since 1990, the PI has been collecting data to build this model and hopes to finish it this year by determining the total body water, water flux, and daily energy expenditure of shearwaters, terns, and noddies at nest sites varying in amount of shade. These determinations can be made by laboratory analysis of blood samples collected in 1991 from birds injected with deuterium or doubly-labeled water. In addition, the PI hopes to analyze the composition of meals, nasal secretions, urine and feces previously collected from the above relative importance of various energy and water balance variables. Some characteristics that may prevent shearwaters from successfully nesting in hot microclimates are long incubation shifts (9 days), infrequent drinking of seawater, and the formation of stomach oils that reduce the amount of gastric space available for water. The model of interacting balances, formed in this study, should be easily modified to evaluate the effect of other types of competing balances on the ecology of organisms. ***

9321759 Ricklefs 能量和质量约束不断相互作用，影响生物体的生态。没有什么地方比筑巢的热带海鸟更清楚地证明了这一点，那里有很强的选择来储存孵化过程中的能量，并在炎热、恶劣的环境中维持水平衡。 在夏威夷群岛西北部，楔尾海鸥会争夺筑巢洞穴，而那些没有洞穴的海鸥（占总数的 44%）必须在地表筑巢。如果这些场所几乎没有受到太阳辐射的保护，那么只有 5-11% 的场所能够产下雏鸡。与海鸥不同的是，乌燕鸥和褐燕鸥经常在阳光下筑巢，并且 85% 的巢穴会产下雏鸟。为了更好地理解在炎热环境中筑巢的能力差异，PI 构建了一个概念模型，将能量和物质平衡联系起来，以便清楚地理解它们之间的相互作用。自 1990 年以来，PI 一直在收集数据来建立这个模型，并希望在今年通过确定海鸥、燕鸥和海鸥在不同遮荫程度的筑巢地点的体内总水分、水通量和每日能量消耗来完成该模型。这些测定可以通过实验室分析 1991 年从注射了氘或双标记水的鸟类中采集的血液样本来做出。此外，PI希望根据上述各种能量和水平衡变量的相对重要性来分析之前收集的膳食、鼻腔分泌物、尿液和粪便的成分。可能阻止海鸥在炎热的小气候中成功筑巢的一些特征是孵化周期长（9天）、不经常饮用海水以及胃油的形成，从而减少了胃中可容纳水的空间。本研究中形成的相互作用平衡模型应该很容易修改，以评估其他类型的竞争平衡对生物体生态的影响。 ***