Abstract Relative contributions of aquaculture-origin and naturally-reproduced grass carp (Ctenopharyngodon idella) in the Laurentian Great Lakes have been unknown. We assessed occurrence and distribution of aquaculture-origin and wild grass carp in the Great Lakes using ploidy and otolith stable oxygen isotope (δ18O) data. We inferred natal river and dispersal from natal location for wild grass carp using otolith microchemistry and estimated ages of wild and aquaculture-origin fish to infer years in which natural reproduction and introductions occurred. Otolith δ18O indicated that the Great Lakes contain a mixture of wild grass carp and both diploid and triploid, aquaculture-origin grass carp. Eighty-eight percent of wild fish (n = 49 of 56) were caught in the Lake Erie basin. Otolith microchemistry indicated that most wild grass carp likely originated in the Sandusky or Maumee rivers where spawning has previously been confirmed, but results suggested recruitment from at least one other Great Lakes tributary may have occurred. Three fish showed evidence of movement between their inferred natal river in western Lake Erie and capture locations in other lakes in the Great Lakes basin. Age estimates indicated that multiple year classes of wild grass carp are present in the Lake Erie basin, recruitment to adulthood has occurred, and introductions of aquaculture-origin fish have happened over multiple years. Knowledge of sources contributing to grass carp in the Great Lakes basin will be useful for informing efforts to prevent further introductions and spread and to develop strategies to contain and control natural recruitment.

中文翻译：

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确定导致劳伦斯大湖中入侵草鱼的来源和年份分类

摘要 劳伦斯大湖中源自水产养殖的草鱼 (Ctenopharyngodon idella) 的相对贡献尚不清楚。我们使用倍性和耳石稳定氧同位素 (δ18O) 数据评估了五大湖中水产养殖源和野草鱼的发生和分布。我们使用耳石微化学和估计野生和水产养殖来源鱼类的年龄来推断野生草鱼的出生河流和从出生地点的扩散，以推断自然繁殖和引入发生的年份。耳石 δ18O 表明五大湖中含有野生草鱼和二倍体和三倍体、水产养殖草鱼的混合物。88% 的野生鱼类（n = 49 of 56）是在伊利湖盆地捕获的。耳石微量化学表明，大多数野生草鱼可能起源于桑达斯基河或莫米河，先前已证实在那里产卵，但结果表明，可能发生了至少来自五大湖其他支流的补充。三条鱼显示出它们在伊利湖西部推断的出生河流与五大湖盆地其他湖泊中的捕获地点之间移动的证据。年龄估计表明，伊利湖流域存在多年级别的野草鱼，已经发生了成年期的招募，并且引入了水产养殖来源的鱼类已经多年。