Age‐0 Walleye Sander vitreus are stocked throughout North America to maintain and supplement populations. Predation has been implicated as a factor limiting survival of stocked age‐0 Walleye; however, the timing, duration, and extent of poststocking predation remains uncertain. Our objectives were to estimate the abundance of predators in areas adjacent to stocking locations, estimate temporal variation in the proportion of stocked age‐0 Walleye (98–287 mm) in predator diets, and estimate the total proportion of stocked age‐0 Walleye that were consumed. The diets of Largemouth Bass Micropterus salmoides, Northern Pike Esox lucius, and adult Walleye were examined in East Okoboji and West Okoboji lakes, Iowa, before and after age‐0 Walleye stocking, and bioenergetics models were used to estimate the number of age‐0 Walleye consumed from stocking through ice‐up. During both years, Largemouth Bass had the highest densities in West Okoboji Lake, whereas densities of all other predators were similar in East Okoboji Lake. The highest proportions of age‐0 Walleye in predator diets (up to 1.0) generally occurred within 14 d after the most recent stocking event, with the proportion of age‐0 Walleye in predator diets decreasing thereafter. Northern Pike had the highest proportion of age‐0 Walleye in their diets (mean ± SD = 0.12 ± 0.32 age‐0 Walleye/individual) followed by Largemouth Bass (0.11 ± 0.30 age‐0 Walleye/individual) and adult Walleye (0.04 ± 0.20 age‐0 Walleye/individual). At the end of 2016, the estimated proportion of age‐0 Walleye consumed was 0.15 ± 0.08 (95% CI) in East Okoboji Lake and 0.29 ± 0.13 in West Okoboji Lake. At the end of 2017, the estimated proportion of age‐0 Walleye consumed was 0.47 ± 0.16 in East Okoboji Lake and 0.64 ± 0.02 in West Okoboji Lake. Overall, predators consumed large proportions of stocked Walleye, suggesting that alternative stocking practices should be considered.

中文翻译：

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使用生物能学估算一组食肉动物对零龄角膜白鲸的消耗

北美地区都有0岁的Walleye Sander玻璃体库存，以维持和补充人口。捕食被认为是限制0岁长角Wall存养的生存的因素。但是，后期库存捕食的时间，持续时间和范围仍不确定。我们的目标是估计与放养地点相邻的区域中的捕食者数量，估计捕食者零食中的年龄-0岁角膜白斑（98-287毫米）所占比例的时间变化，并估计被消耗了。大口黑鲈的饮食加州鲈，白斑狗鱼白斑狗鱼在爱荷华州-0岁角膜幼体放养之前和之后，对爱荷华州东奥科波吉湖和西奥科波吉湖成年角膜白斑进行了检查，并利用生物能学模型估算了从冰蓄冰到放养所消耗的0岁角膜幼体的数量。在这两年中，大口黑鲈在西奥科波吉湖中的密度最高，而所有其他捕食者的密度在东奥科波吉湖中相似。在最近的放养事件后的14天内，捕食者中0岁角膜白斑的比例最高（最高1.0），此后捕食者中0岁角膜白斑的比例下降。在饮食中，Northern Pike的0岁角膜白斑比例最高（平均±SD = 0.12±0.32 0岁角膜白斑/个体），其次是大嘴鲈鱼（0.11±0.30岁0角膜白斑/个体）和成年角膜白斑（0.04± 0.20年龄-0角膜白斑/个体）。截至2016年底，东部Okoboji湖的估计0岁角膜白眼所消耗的比例为0.15±0.08（95％CI），而西部Okoboji湖的估计比例为0.29±0.13。截至2017年底，东部Okoboji湖的估计0岁角膜白眼所消耗的比例为0.47±0.16，而西部Okoboji湖的估计比例为0.64±0.02。总体而言，捕食者消耗了大量的角膜白斑，这表明应该考虑其他的放养方式。