A series of rock jetty and A‐Jack structures was built in 1998 at Branched Oak Reservoir, Nebraska, in an attempt to reduce shoreline erosion and cove degradation. In conjunction with the habitat enhancement project, Flathead Catfish Pylodictis olivaris were stocked to help control the abundant White Perch Morone americana population. Previous research found that Flathead Catfish utilized the habitats created by the enhancement project; however, the research was conducted while the Flathead Catfish population was still developing and the reservoir water elevation was held for an extended period below conservation pool. We sampled three habitat types (rock jetty structures, concrete A‐Jack structures, and new‐growth trees) during the summer months from 2015 to 2019 using daytime low‐frequency electrofishing to determine differences in size distribution and relative abundance among habitat types. Flathead Catfish utilization of the rock jetty structures was characterized by high catch rates (137 fish/h) and smaller fish (<400 mm). Lower catch rates were found in the A‐Jack structures (86 fish/h) and new‐growth trees (36 fish/h); however, these habitats were primarily utilized by larger fish (>600 mm). Habitat use changed with the developing population and the availability of a new habitat type, inundated new‐growth trees. The catch‐and‐release regulation changed both density and size structure of the Flathead Catfish population in Branched Oak Reservoir. The results of this study can assist fisheries managers in locating or enhancing favorable reservoir habitats for Flathead Catfish.

中文翻译：

---

美国内布拉斯加州分支橡树水库中捕捞和释放调节的Reg鱼种群栖息地使用评估

为了减少海岸线侵蚀和海湾退化，1998年在内布拉斯加州分支橡树水库建造了一系列的岩石码头和A-Jack结构。结合栖息地改善项目，平头Flat鱼Pylodictis olivaris被放养，以帮助控制丰富的美洲白鲈人口。先前的研究发现，扁平头Cat鱼利用了增强项目创造的栖息地。但是，该研究是在扁平头Cat鱼种群仍在发育且水库水位保持在保护池以下一段较长时间内进行的。我们在2015年至2019年夏季使用白天低频电鱼捕捞对三种栖息地类型（岩石码头结构，混凝土A-Jack结构和新生长树）进行了采样，以确定栖息地类型之间的大小分布和相对丰度差异。平头Cat鱼利用岩石码头结构的特点是捕获率高（137条鱼/小时）和小鱼（<400毫米）。在A-Jack结构（每小时86条鱼）和新树（每小时36条鱼）中发现较低的捕获率；然而，这些栖息地主要被较大的鱼类（> 600毫米）利用。生境的使用随着人口的增长和新栖息地类型（新生长树被淹没）的可用性而改变。捕捞和释放法规改变了分支橡树水库中Flat鱼种群的密度和大小结构。这项研究的结果可以帮助渔业管理者找到或改善平头鱼的有利水库栖息地。