Abstract Understanding the relationship between a species and its habitats is important for both conservation of imperiled species and control of invasive species. For migratory species, we hypothesize that maintaining connectivity between segregated habitats is more important than improving the quality of each habitat. In the case of anadromous lampreys of conservation concern, we posit that restoring passage routes between spawning, rearing and feeding habitats will result in higher larval abundance upstream from barriers than efforts to improve quality of these freshwater habitats. To explore this hypothesis, we reviewed conservation actions for native anadromous lampreys in freshwater and found that: i) improving passage between habitats results in immediate and quantifiable increases in larval abundance, ii) anadromous lampreys are capable of existing in suboptimal habitats, and iii) small reservoirs of production drive rapid expansion when anadromous lampreys are released from passage constraints. Hence, maintaining habitat connectivity is clearly crucial for conservation of anadromous lampreys. There are fewer examples of improvements to freshwater habitat that increased larval lamprey abundance, perhaps because lampreys are rarely the focus of these efforts. However, habitat limitations such as stream de-watering, chemical pollution, and scour occur and will likely be exacerbated by climate change. Documenting habitat actions that reverse these problems may provide evidence for the merits of lamprey-specific habitat improvement. Our observations are relevant to sea lamprey control in the Great Lakes because barriers and chemical treatment are key instruments of population regulation, and can be strategically deployed to limit production.

中文翻译：

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溯河七鳃鳗的通道和淡水栖息地要求：保护和控制的考虑

摘要 了解物种与其栖息地之间的关系对于濒危物种的保护和入侵物种的控制都很重要。对于迁徙物种，我们假设保持隔离栖息地之间的连通性比提高每个栖息地的质量更重要。就保护问题的溯河七鳃鳗而言，我们假设恢复产卵、饲养和觅食栖息地之间的通道将导致屏障上游的幼虫丰度高于改善这些淡水栖息地质量的努力。为了探索这一假设，我们回顾了淡水中原生溯河七鳃鳗的保护行动，发现：i) 改善栖息地之间的通道会导致幼虫丰度立即和可量化的增加，ii) 溯河七鳃鳗能够存在于次优生境中，以及 iii) 当溯河七鳃鳗从通道限制中释放时，小型生产水库会推动快速扩张。因此，保持栖息地连通性对于保护溯河七鳃鳗显然至关重要。改善淡水栖息地增加幼体七鳃鳗丰度的例子较少，也许是因为七鳃鳗很少成为这些努力的重点。然而，栖息地的限制，如河流脱水、化学污染和冲刷，可能会因气候变化而加剧。记录扭转这些问题的栖息地行动可能为七鳃鳗特定栖息地改善的优点提供证据。