Haas Taylor F, Castro-Santos Theodore, Miehls Scott M, Deng Zhiqun D, Bruning Tyler M, Wagner C Michael
Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, East Lansing, MI USA.
U.S. Geological Survey, Eastern Ecological Science Center, S.O. Conte Research Laboratory, Turners Falls, MA USA.
Anim Biotelemetry. 2023;11(1):9. doi: 10.1186/s40317-023-00318-1. Epub 2023 Mar 11.
Little is known about the transformer stage of the parasitic lampreys, a brief but critical period that encompasses juvenile out-migration from rivers to lakes or oceans to begin parasitic feeding. Information about this life stage could have significant conservation implications for both imperiled and invasive lampreys. We investigated tag retention, survival, wound healing, and swim performance of newly transformed sea lamprey () implanted with a new micro-acoustic transmitter, the eel-lamprey acoustic transmitter (ELAT), in a controlled laboratory environment.
The 61-day survival of our tagged subjects was 71%, within the range reported in similar studies of juvenile lampreys. However, survival was significantly lower in the tagged animals (vs control), with no effect statistically attributable to measures of animal length, mass, condition, or population of origin (Great Lakes vs. Atlantic drainage). Mortality in tagged fish was concentrated in the first four days post-surgery, suggesting injury from the surgical process. An unusually long recovery time from anesthesia may have contributed to the increased mortality. In a simple burst swim assay, tagged animals swam significantly slower (- 22.5%) than untagged animals, but were not significantly different in endurance swim tests. A composite wound healing score at day four was a significant predictor of maximum burst swim speed at day 20, and wound condition was related to animal mass, but not length, at the time of tagging.
Impairments to survival and swim performance of juvenile sea lamprey implanted with the ELAT transmitter were within currently reported ranges for telemetry studies with small, difficult to observe fishes. Our results could be improved with more refined anesthesia and surgical techniques. The ability to track migratory movements of imperiled and pest populations of parasitic lampreys will improve our ability to estimate vital rates that underlie recruitment to the adult population (growth, survival) and to investigate the environmental factors that regulate the timing and rates of movement, in wild populations.
对于寄生七鳃鳗的变态阶段，人们了解甚少。这是一个短暂但关键的时期，包括幼体从河流洄游到湖泊或海洋开始寄生摄食。关于这个生命阶段的信息对于濒危和入侵性七鳃鳗的保护可能具有重要意义。我们在可控的实验室环境中，研究了植入新型微声学发射器——鳗鱼-七鳃鳗声学发射器（ELAT）的新变态海七鳃鳗（）的标记保留、存活、伤口愈合及游泳能力。
我们标记的实验对象61天的存活率为71%，在类似幼体七鳃鳗研究报告的范围内。然而，标记动物的存活率显著低于未标记动物（与对照组相比），且在统计学上，动物的体长、体重、健康状况或来源种群（五大湖与大西洋水系）均无显著影响。标记鱼的死亡集中在手术后的头四天，表明手术过程造成了损伤。麻醉后的恢复时间异常长可能导致了死亡率增加。在简单的爆发式游泳试验中，标记动物的游泳速度比未标记动物显著慢（- 22.5%），但在耐力游泳测试中无显著差异。第4天的综合伤口愈合评分是第20天最大爆发式游泳速度的显著预测指标，且伤口状况与标记时动物的体重相关，但与体长无关。
植入ELAT发射器的幼年海七鳃鳗在存活和游泳能力方面的损伤在目前关于小型、难以观察鱼类的遥测研究报告范围内。采用更精细的麻醉和手术技术可改善我们的研究结果。追踪濒危和有害寄生七鳃鳗种群洄游运动的能力，将提高我们估计构成成年种群补充（生长、存活）基础的生命率的能力，并有助于研究调节野生种群运动时间和速度的环境因素。
