Positive mortality effects in container mosquitoes

Cohorts of 150 newly-hatched <i>Aedes aegypti, A. albopictus, A. triseriatus, </i>and <i>Culex pipiens</i> were separately reared in 500 mL plastic containers. Cohorts were randomly assigned a treatment of either simulated mortality random harvest of 0, 10, 30, 50, or 70% removal on day 2 of the experiment, or mortality from predation by 1, 2, or 3 female <i>Mesocyclops longisetus </i>added on day 0 and removed on day 2. Any random harvest treatment cohorts that had fewer survivors than the number required to simulate their assigned mortality percentages from 150 had larvae added to reach the appropriate number. The conspecific larvae removed from other harvest treatments were used for these additions to ensure they were reared under the same conditions. On day 2, the number of survivors was counted for each cohort, and the amount of mortality experienced up to that point (Day2mort) was calculated as (#survivors - 150)/150. The experiment was conducted in 8 unbalanced temporal blocks. Four days prior to the start of the experiment, the experimental containers were filled with 400mL reverse-osmosis water, 1g dried live oak (<i>Quercus virginiana</i>) leaves, 0.05g dried decorated crickets (<i>Gryllodes sigillatus</i>), and 100 microliters microbial inoculum collected from a rain-filled bucket. Lids were placed on the containers with holes punched for ventilation. 0.5g dried oak leaves and 0.025g dried decorated crickets were added on days 16 and 30 for the three <i>Aedes </i>species cohorts and on days 9, 16, 23, and 30 for the <i>C. pipiens </i>cohorts. Containers were housed in an environmental chamber at 25C with a 14:10 light:dark photoperiod throughout the experiment.Containers were checked daily for pupae, which were removed, placed in glass vials with water and cotton stoppers, and housed in the same environmental chamber. Pupae were checked daily for adults, which were removed and sexed. The number of days to pupation (DaystoP) and to adulthood (DaystoA) were recorded for each individual.

初孵的150只埃及伊蚊（Aedes aegypti）、白纹伊蚊（Aedes albopictus）、三列伊蚊（Aedes triseriatus）以及淡色库蚊（Culex pipiens）的实验队列，分别置于500mL塑料容器中饲养。将各实验队列随机分配至两种处理组：其一为模拟死亡的随机收获组，即在实验第2天按0%、10%、30%、50%或70%的比例移除幼虫；其二为捕食致死组，即在实验第0天放入1、2或3只雌性长肢中剑水蚤（Mesocyclops longisetus），并于第2天移除该捕食者。对于随机收获组的队列，若其存活幼虫数量低于按初始150只计算的指定移除比例所需的存活数，则补充同种幼虫至对应数量。从其他收获组队列中移除的同种幼虫将被用于此类补充，以保证所有幼虫均处于相同饲养条件。实验第2天，统计每个队列的存活幼虫数量，并计算截至该时点的累计死亡率（Day2mort），计算公式为（存活个体数 - 150）/150。本实验在8个非平衡时间区组中开展。实验开始前4天，向实验容器中加入400mL反渗透水、1g干燥弗吉尼亚栎（Quercus virginiana）叶片、0.05g干燥装饰蟋蟀（Gryllodes sigillatus）成虫，以及从雨水桶中采集的100μL微生物接种物。为容器加盖并打孔以保证通风。针对3种伊蚊属队列，分别于实验第16天和第30天添加0.5g干燥栎叶与0.025g干燥装饰蟋蟀；针对淡色库蚊（C. pipiens）队列，则于第9、16、23和30天添加上述两种饵料。整个实验期间，容器均置于温度为25℃、光暗周期为14:10的人工气候箱中饲养。每日检查容器内的蛹，将其取出后放入盛有水并塞有棉塞的玻璃管中，继续置于同一人工气候箱内。每日检查蛹的羽化情况，将羽化出的成虫取出并进行性别鉴定。记录每头幼虫的化蛹天数（DaystoP）与羽化天数（DaystoA）。