Bullheads Ameiurus spp. are found throughout much of the United States and are infrequently studied species. Although limited information has been published on the Black Bullhead A. melas and Yellow Bullhead A. natalis, it has been shown that bullheads can dominate the fish biomass in some north temperate U.S. lakes, resulting in a fish community exclusive of Walleye Sander vitreus and Yellow Perch Perca flavescens. Recently, recruitment and abundances of popular coolwater sport fishes, such as Walleye and Yellow Perch, have been declining in some northern Wisconsin lakes. These observed declines, coupled with high bullhead densities, led fisheries biologists to conduct whole‐lake bullhead removals on four northern Wisconsin lakes. Removal of Black and Yellow bullheads from these lakes resulted in substantial changes in the fish communities. The CPUE of naturally reproduced age‐0 Walleye increased in Lake Metonga and Patten Lake following the removal of bullheads. Additionally, survival of stocked Walleye increased in Crane and Pickerel lakes after bullhead removals, resulting in higher CPUE of age‐0 and age‐1 Walleye. Subsequently, adult Walleye abundance has increased or remained steady in all bullhead removal lakes. Significant declines in abundance of Bluegill Lepomis macrochirus and increases in abundance of Yellow Perch and Black Crappie Pomoxis nigromaculatus were also observed after bullhead removals, further illustrating a shift in fish community composition. Our observations suggest that when at high densities, bullheads can play a significant role in structuring fish communities and the removal of bullheads can increase recruitment, survival, and abundance of sport fishes like Walleye and Yellow Perch.

中文翻译：

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与威斯康星州北部的四个湖泊中的牛头去除相关的鱼类群落变化

Bullheads Ameiurus spp。被发现在美国大部分地区，是不经常研究的物种。尽管在Black Bullhead A. melas和Yellow Bullhead A. natalis上发布的信息有限，但已经表明，在美国北部温带湖泊中，牛头菌能控制鱼类的生物量，从而形成了不包括Walleye Sander玻璃体和黄色的鱼群落。鲈鱼河鲈苦参。最近，威斯康星州北部的一些湖泊中，诸如Walleye和Yellow Perch之类的流行冷水运动鱼类的招募和丰富度正在下降。这些观测到的下降，加上高的bull头密度，导致渔业生物学家对威斯康星州北部的四个湖泊进行了整湖bull头清除。从这些湖泊中清除黑头和黄头鱼导致了鱼类群落的巨大变化。去除牛头后，默顿加湖和帕滕湖的自然繁殖0岁角膜白斑的CPUE有所增加。此外，去除牛头后，克兰和皮克雷尔湖中存养的角膜白斑的存活期增加，导致0岁和1岁的角膜白斑的CPUE升高。随后，成年的角膜白鲑在所有去除牛头的湖泊中的丰度增加或保持稳定。去除牛头后还观察到了Lepomis macrochirus和黄鲈和Black Crappie Pomoxis nigromaculatus的丰度增加，进一步说明了鱼类群落组成的变化。我们的观察结果表明，在高密度时，bull鱼可以在构造鱼类群落中发挥重要作用，而去除bull鱼可以增加捕食，存活和丰度丰富的运动鱼（如Walleye和Yellow Perch）。