Consequences of Larval Interactions to Mayfly Survival, Fecundity and Population Growth

幼虫相互作用对蜉蝣生存、繁殖力和种群增长的影响

• 批准号: 9306842
• 负责人: Barbara Peckarsky
• 金额: $ 27.52万
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-01-01 至 1997-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306842&HistoricalAwards=false
• 关键词: Consequences; Larval; Interactions; Mayfly; Survival

9306842 Peckarsky The objectives of the proposed research are to (1) determine how much of the death rate of the stream-dwelling larval mayfly, Baetis bicaudatus, is due to stonefly and trout predation, and to parasitism by nematode worms, (2) measure the consequences of reduced feeding by mayflies while avoiding competitors, predatory stoneflies and trout in terms of female egg production and size-related male mating success, and (3) using methods to estimate mayfly population growth, determine the relative impacts of predators, parasites and competitors on the mayflys' ability to sustain populations over the long term. Meathods proposed to meet those objectives include: (a) experiments conducted in small (25cm) and large (1.5m) enclosures to measure the effects of stonefly and trout predation on mayfly death rate, (b) behavioral experiments to determine the risk of trout predation to mayflies that have entered the water column to escape stonefly predation, (c) dissections of mayfly larvae and adults to estimate stages and sexes of infection, sterilization and death cause by nematode worms, and (d) experiments conducted in small and large enclosures to measure the effects of predator on mayfly growth rates, sizes of adults and egg production, (e) field experiments will determine whether larger male mayflies have greater mating success, and (f) sizes and egg production and mayflies that completed their larval stage in sites or streams with different densities of predators competitors. These data will illustrate whether any effects of predator avoidance observed at a smaller scale (in enclosures) can be detected a t larger scales in natural streams. Data from these experiments will be used to compare mayfly population growth in the face of stonefly and trout predators, parasites and competitors. Filed estimates of mayfly population growth will be obtained as a "reality check" on experimentally derived population growth rates. The key contribution of this research is a unique investigation of connections between factors affecting larval morality and behavior and adult reproductive success. No previous studies have compared the consequences of a suite of selection pressures such as predation, parasitism and competition on one stage of a natural population, and interpreted these impacts on population growth in context of the complete life cycle. $ ! ! !8 ! F ( Times New Roman Symbol & Arial * " h k k 7 Crystal Blackshear Crystal Blackshear

9306842 Peckarsky 拟议研究的目标是 (1) 确定溪流中的蜉蝣幼虫 Baetis bicaudatus 的死亡率有多少是由于石蝇和鳟鱼的捕食以及线虫的寄生造成的，(2) 测量蜉蝣取食减少的后果，同时避免竞争对手、捕食性石蝇和鳟鱼在雌性产卵和 与体型相关的雄性交配成功率，以及（3）使用估计蜉蝣种群增长的方法，确定捕食者、寄生虫和竞争者对蜉蝣长期维持种群能力的相对影响。 为实现这些目标而提出的方法包括：（a）在小（25cm）和大（1.5m）围栏中进行实验，以测量石蝇和鳟鱼捕食对蜉蝣死亡率的影响，（b）行为实验，以确定鳟鱼捕食进入水体以逃避石蝇捕食的蜉蝣的风险，（c）解剖蜉蝣幼虫和成虫，以估计蜉蝣的阶段和性别 线虫引起的感染、绝育和死亡；(d) 在小型和大型围栏中进行的实验，以测量捕食者对蜉蝣生长速度、成虫体型和产卵量的影响；(e) 田间实验将确定较大的雄性蜉蝣是否具有更高的交配成功率；(f) 在具有不同捕食者竞争者密度的地点或溪流中完成幼虫阶段的蜉蝣的大小和产卵量以及完成幼虫阶段的蜉蝣。 这些数据将说明在较小规模（在围栏内）观察到的躲避捕食者的影响是否可以在较大规模的自然溪流中检测到。 这些实验的数据将用于比较蜉蝣在石蝇和鳟鱼捕食者、寄生虫和竞争对手面前的种群增长情况。 蜉蝣种群增长的归档估计值将作为对实验得出的种群增长率的“现实检验”而获得。 这项研究的关键贡献是对影响幼虫道德和行为的因素与成虫繁殖成功之间的联系进行了独特的调查。 之前的研究还没有比较自然种群某一阶段的捕食、寄生和竞争等一系列选择压力的后果，并在整个生命周期的背景下解释这些对种群增长的影响。 $！ ！ ！8！ F ( Times New Roman 符号 & Arial * " h k k 7 Crystal Blackshear Crystal Blackshear