Ballast water moved by transoceanic vessels has been recognized globally as a predominant vector for the introduction of aquatic nonindigenous species (NIS). In contrast, domestic ships operating within confined geographic areas have been viewed as low risk for invasions, and are exempt from regulation in consequence. We examined if the St. Lawrence River could serve as a source of NIS for the Laurentian Great Lakes by surveying ballast water carried by domestic vessels and comparing biological composition in predominant St. Lawrence River-Great Lakes port-pairs in order to determine the likelihood that NIS could be transported to, and survive in, the Great Lakes. Thirteen potential invaders were sampled from ballast water, while 26 taxa sampled from St. Lawrence River ports are not reported from the Great Lakes. The majority of NIS recorded in samples are marine species with low potential for survival in the Great Lakes, however two euryhaline species (copepod Oithona similis, and amphipod Gammarus palustris) and two taxa reported from brackish waters (copepod Microsetella norvegica and decapod Cancer irroratus) may pose a risk for invasion. In addition, four marine NIS were collected in freshwater samples indicating that at least a subset of marine species have potential as new invaders to the Great Lakes. Based on results from this study, the ports of Montreal, Sorel, Tracy and Trois Rivières appear to pose the highest risk for new ballast-mediated NIS from the St. Lawrence River to the Great Lakes.

中文翻译：

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国内船只是从圣劳伦斯河到五大湖的非本土物种的潜在途径。

经跨洋运输的压载水已被公认为引入水生非本地物种（NIS）的主要媒介。相反，在受限地理区域内作业的国内船舶被视为入侵风险低，因此不受管制。我们调查了圣劳伦斯河-大湖港主要港口对中的压载水，并比较了生物组成，从而研究了圣劳伦斯河是否可以作为劳伦斯大湖的NIS来源。可以将NIS运送到大湖地区并在其中生存。从压舱水中取样了十三种潜在入侵者，而从大劳克斯湖中未报告从圣劳伦斯河港口取样的二十六个分类单元。样本中记录的大多数NIS是在大湖地区具有较低生存潜力的海洋物种，但是据报道有两种淡水鱼类（足脚纲Oithona similis和两栖纲伽马兽palustris）和两种分类群来自微咸水域（足足纲Microsetella norvegica和十足纲巨蟹座irroratus）可能会造成入侵的危险。此外，在淡水样品中收集了四个海洋NIS，表明至少有一部分海洋物种具有作为五大湖新入侵者的潜力。根据这项研究的结果，从圣劳伦斯河到大湖地区，蒙特利尔，索雷尔，特雷西和三河沿岸的港口对于新的压舱物介导的NIS构成最高风险。和两栖类Gammarus palustris）和半咸水报告的两个类群（足足类Microsetella norvegica和十足类癌症irroratus）可能构成入侵的风险。此外，在淡水样品中收集了四个海洋NIS，表明至少有一部分海洋物种具有作为五大湖新入侵者的潜力。根据这项研究的结果，从圣劳伦斯河到大湖地区，蒙特利尔，索雷尔，特雷西和三河沿岸的港口对于新的压舱物介导的NIS构成最高风险。和两栖类Gammarus palustris）和半咸水报告的两个类群（足足类Microsetella norvegica和十足类癌症irroratus）可能构成入侵的风险。此外，在淡水样品中收集了四个海洋NIS，表明至少有一部分海洋物种具有作为五大湖新入侵者的潜力。根据这项研究的结果，从圣劳伦斯河到大湖地区，蒙特利尔，索雷尔，特雷西和三河沿岸的港口对于新的压舱物介导的NIS构成最高风险。