AGE-0 SILVER CARP AND GIZZARD SHAD DAILY GROWTH AND HATCH TIMING IN THE MIDDLE MISSISSIPPI RIVER

作     者：WOLF Michael C. HAUPT Kevin PHELPS Quinton E. WOLF Michael C.;HAUPT Kevin;PHELPS Quinton E.

作者机构：Department of Natural ResourcesFish and Wildlife Division204 Main Street East BaudetteMinnesota 56623USA U.S.Fish and Wildlife ServiceCarterville Fish and Wildlife Conservation Office 9053 Rt.148 Suite A MarionIllinois 62959USA West Virginia UniversityDivision of Forestry and Natural Resources307C Percival HallMorgantownWest Virginia 26505USA 

出 版 物：《水生生物学报》 (Acta Hydrobiologica Sinica)

年 卷 期：2018年第42卷第6期

页      面：1084-1088页

核心收录：

学科分类：090803[农学-渔业资源] 0908[农学-水产] 09[农学] 

主　　题：Dorosoma cepedianum Silver carp 

摘      要：The establishment of a highly efficient planktivore, Silver carp(Hypophthalmichthys molitrix), in the Mississippi River Basin has been documented as having negative impacts on native planktivore populations. Silver carp have the potential, to alter the trophic food web through negative interactions with native planktivores in large river systems. Due to increasing Silver carp ranges, interactions between Silver carp and other native planktivores is likely to increase. One abundant native planktivore that is often found in similar habitats as Silver carp is Gizzard shad(Dorosoma cepedianum). Potential competition for resources exists because of overlapping habitat use and forage. Given the similarities between these two planktivores, we sought to evaluate daily growth rates and determine hatch dates of age-0 Silver carp and Gizzard shad in the Middle Mississippi River. Silver carp and Gizzard shad were collected from the Middle Mississippi River using an electrified surface trawl from June through September with sizes ranging from 21—65 mm total length for Gizzard shad and 24—85 mm total length for Silver carp. A sample of age-0 fish(n=697) was collected at the end of the growing season including 292 Gizzard shad and 405 Silver carp. Size structure(total length in mm) of Silver carp(49.05±0.41; ± SE) was significantly greater(T= –16.43, df=695, P0.001) than Gizzard shad(38.95 ± 0.45). Hatch dates were similar between Silver carp(July 26 th to August 18 th) and Gizzard shad(July 28 th to August 19 th). Growth of Silver carp(2.24 mm per day) was significantly greater(P0.001,T= –11.1, df=82) than Gizzard shad(1.72 mm per day). Mortality was similar between Silver carp(28.1%)and Gizzard shad(25.1%) at this early life stage. The faster growth rates in Silver carp result in Silver carp entering the winter season larger in size with likely an increased capacity to consume plankton and decreased predation ultimately leading to higher recruitment. Knowing that there exists