Tag retention and survival of juvenile bighead carp implanted with an acoustic tag at three temperatures

Bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix (together, the bigheaded carps) are considered among the most problematic of invasive fishes in North. Movement and behavior of bigheaded carps has been studied through telemetry methods although the majority of work has occurred on large, adult fish; smaller, juvenile bigheaded carps have not yet been evaluated. Reductions in the size of transmitters have provided an opportunity for such work. However, the effects of surgical implantation of telemetry tags on small bigheaded carps have not previously been evaluated. The goal of this study was to determine tag retention and survival associated with implanting acoustic tags into small bighead carp (range 128-152 mm total length) at three separate temperatures (13 degrees C, 18 degrees C, and 23 degrees C), as well as determining differences in fitness of the carp, defined as changes in weight or critical swimming speed.

鳙鱼（Hypophthalmichthys nobilis）与鲢鱼（Hypophthalmichthys molitrix，二者合称为大头鲤类）被认为是北美地区危害最为严重的外来入侵鱼类之一。当前针对大头鲤类的运动与行为研究多采用遥测技术（telemetry）开展，但绝大多数研究对象为大型成体个体，小型幼体大头鲤类的相关评估尚未见报道。遥测发射器（transmitters）尺寸的缩减为这类研究提供了可行条件，但此前尚无针对小型大头鲤类开展外科植入遥测标签影响的相关评估。本研究旨在探究：在13℃、18℃及23℃三种水温条件下，向总长度为128~152mm的小型鳙鱼体内植入声学标签（acoustic tags）后的标签留存率与存活率，并评估该手术对鱼类健康状态的影响——以体重变化或临界游泳速度（critical swimming speed）的改变作为健康状态的衡量指标。