Seal-Induced Injuries on Adult Atlantic Salmon Returning to Maine

AbstractSeals (Phocidae) are known predators of Atlantic Salmon Salmo salar from their entry into the estuary as smolts until their return to freshwater as adults. We developed a written protocol for identifying seal-induced injuries on adult Atlantic Salmon returning to Maine rivers. The protocol, which includes photos and category definitions, has been used since 2006 by Maine Department of Marine Resources biologists when handling adult Atlantic Salmon at the Veazie Dam fishway on the Penobscot River and at other adult capture facilities in Maine. The written protocol has ensured that reporting is consistent among years and rivers; photos of wounds serve as quality assurance for the protocol. For adults returning to the Penobscot River in 2006 and 2007, seal-induced injuries were more likely to be found on two-sea-winter fish; to appear as gashes or arched wounds; to be open rather than healed; and to occur on the center third of the body below the lateral line. Larger two-sea-winter fish (>67 cm FL) r...