编辑“︁鮭魚”︁（章节）

===與七鰓鰻的關係===
[[File:Chinook salmon (Garden R) crop.jpg|thumb|被七鳃鳗啃伤的[[帝王鲑]]]]
有研究發現，當[[七鰓鰻]]的數量減少，鮭魚的數量亦會隨之減少。和鲑鱼一样，许多七鳃鳗是洄游鱼种，在产卵后会死亡并腐烂向河溪中释放营养；而且与[[虹鳟]]和[[亚口鱼科#亞口魚屬（Catostomus）|亚口鱼]]一样，七鳃鳗在产卵时对水底的砾石会有清洁作用<ref>{{cite web | date = 19 January 2010 | title = Yuba River Steelhead Redd Surveys (preliminary draft) | url = http://www.yubaaccordrmt.com/Study%20Protocols/Steelhead%20Redd%202010%20Study%20Plan%201-19-10%20(deepwater%20strikeout).pdf | archive-url = https://web.archive.org/web/20180429222315/http://www.yubaaccordrmt.com/Study%20Protocols/Steelhead%20Redd%202010%20Study%20Plan%201-19-10%20(deepwater%20strikeout).pdf | archive-date = 29 April 2018 | url-status = live | publisher =  Yuba River Management Team (RMT) Web Site, Yuba County Water Agency }}</ref>。虽然一些七鳃鳗是[[吸血 (生物学)|吸血]]的[[寄生]]鱼种，但七鳃鳗的[[幼体]]是[[滤食性动物]]可以保持当地水体的健康，而且作为[[体脂肪率|体脂]]和[[鱼油|油性]]都更高的鱼种不但可以作为幼鲑捕食的食物，还可以优先吸引其他捕食者为幼鲑降低生存压力<ref>{{cite news | title = Elder's devotion to ugly fish lives on after his tragic death | date = 20 August 2014 | url = http://america.aljazeera.com/articles/2014/8/20/save-the-lampreyelmercrow.html | work = Al Jazeera America | archive-url = https://web.archive.org/web/20181116074100/http://america.aljazeera.com/articles/2014/8/20/save-the-lampreyelmercrow.html | archive-date = 16 November 2018 | url-status = live}}</ref>。在海中，成年七鳃鳗也是[[海豹]]和[[海狮]]的优先猎物（捕食七鳃鳗和鲑鱼的比例大概为30:1），使得更多的成年鲑鱼可以存活并洄游到河中繁殖<ref>{{cite news | title = Pacific Lamprey's Big Year | date = 18 June 2017 | url = http://kymkemp.com/2017/06/18/pacific-lampreys-big-year/ | work = Redheaded Blackbelt | archive-url = https://web.archive.org/web/20181116062430/http://kymkemp.com/2017/06/18/pacific-lampreys-big-year/ | archive-date = 16 November 2018 | url-status = live}}</ref><ref>{{cite web | year = 2014 | title = A Primeval Marvel | url = http://terra.oregonstate.edu/files/2014/01/Terra-all-pages-single.pdf | work = terra | publisher = Oregon State University | volume = 9 | number = 2 | archive-url = https://web.archive.org/web/20180503042128/http://terra.oregonstate.edu/files/2014/01/Terra-all-pages-single.pdf | archive-date = 3 May 2018 | url-status = live}}</ref>。