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To evaluate mortality of landlocked Atlantic salmon (Salmo salar) caught on flies and worms in a typical river nursery area, a study was carried out at the East Outlet of Moosehead Lake, Maine, in June 1975‐1977. Of 177 fish caught in the 3 yr, 22% died after hooking. All of the 74 control fish caught in a fishway trap survived. Mortality of worm‐hooked fish (35%) was significantly greater than that of fish hooked on flies (4%). Higher mortality of worm‐hooked fish was attributed largely to anatomical site of hooking. Nearly 37% of worm‐caught fish were hooked in the esophagus, but most fly‐caught fish were hooked either in the jaws or mouth. Mortality of fish that bled after hooking (86%) was significantly greater than that of nonbleeding fish (15%). No significant differences were found between hooking mortality of fish of ages II and III nor between legal size (≳356 mm) and sublegal fish. We concluded that closure of heavily fished landlocked Atlantic salmon nursery areas to worm fishing may be justified in areas where juvenile fish production is important to the lake or river fisheries involved.

Experiments to evaluate mortality of age I+ hatchery‐reared landlocked Atlantic salmon (Salmo salar) caused by hooking with four terminal gear types were conducted at the Cobb Fish‐cultural Station, Enfield, Maine in fall, 1972–1974. For the 3 study years, there was an overall mortality of only 3.3% for 1,200 salmon caught by angling, and a mortality of only 0.3% for control fish. Of the total mortality of angled fish, 42.5% occurred within the first 24 hours. Worm‐hooked salmon suffered significantly greater mortality (5.7%) than fish caught on all hardware (single‐ and treble‐hook data combined) (P < 0.001) and by single‐hook hardware only (P < 0.01). Fly‐hooked salmon mortality (4.6%) was significantly greater (P < 0.01) than mortality of fish hooked on all hardware. There was no significant difference in mortality between worm‐hooked and fly‐hooked salmon. Mortality caused by hooking with worms was primarily from fish hooked in the eye (76%) and gill or gill arch (12%). Fly‐caught mortalities had been hooked mainly in the isthmus or tongue (42%), esophagus or stomach (25%), and eye (25%).

To evaluate hooking mortality of lake‐angled landlocked Atlantic salmon (Salmo salar), angled and net‐trapped (control) fish were held for 5 days after capture in each spring and fall for 4 yr. Angled fish suffered a significantly greater mortality than controls in both spring (P < 0.001) and fall (P < 0.05). Mortality of fall‐angled salmon was significantly less than that of spring‐angled fish (P < 0.01). No significant differences (P > 0.05) were found between hooking mortality of age II and III fish, nor between legal‐sized (⩾356 mm, total length) and sublegal salmon. Most mortality occurred within 24 h of hooking. No significant differences (P > 0.05) were found between mortality caused by single‐ and treble‐hook gears, nor between flies and lures. Mortality of gill‐hooked fish was significantly greater (P < 0.001) than that of salmon hooked in the mouth area. No particular gear, hook, or lure type was more prone to hook fish in vital anatomical locations. Mortality of fish bleeding from hooking was significantly greater (P < 0.001) than that of nonbleeding fish. Hooking deaths (y) were predicted accurately from accumulated angler‐hours (x) by the formula: y = 2.772 + 0.029x.

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