That the activities of commercial fishermen have caused mortality of marine birds surprises no one nowadays. Traditions of exploitation of marine birds by fishermen date from previous centuries, and fishing has contributed to the extinction of some species. For example, great auks (Pinguinus impennis) and other birds were used as food by fishermen fishing for Atlantic cod (Gadus morhua) on the Grand Banks of Newfoundland since the beginning of that fishery in the early 16th century (Collins 1884; Lucas 1890). The last great auk died in 1844, but smaller species, such as storm-petrels (Hydrobatidae), greater shearwaters (Puffinus gravis), and black-legged kittiwakes (Rissa tridactyla), were used for food until rather recently (Templeman 1945). This practice has now lapsed, however.
Inshore Fisheries
Until the advent of the offshore salmon gill-net fisheries in the North Pacific in 1952 and the North Atlantic in 1965, most seabird mortality in these areas was the result of local fishing close to shore. Several records of such bird mortality have been published. For example, 8,000-10,000 seabirds—presumably mostly alcids—were reported caught annually off Hammerfest in northern Norway (Holgersen 1961). E. Brun (personal communication) reported that the longline fishery off the coast of Norway is having serious consequences on Norwegian populations of murres.
Numbers of alcids are caught in nets set for Atlantic salmon (Salmo salar) around the coasts of Ireland and Scotland (Biddy 1971). A similar situation exists along the west Greenland coast, although it is overshadowed there by the direct exploitation of huge numbers of alcids by hunting. Nonetheless, in 1967 for example, 15,000 alcids were recovered from fish nets in southwestern Greenland, where they were sold as food (Evans and Waterston 1976). The annual salmon catch of the west Greenland inshore fishery has fluctuated between 60 and 1,500 metric tons and has averaged about 1,000 tons. There are no data comparing the relative catch of birds and fish in this fishery.
Atlantic cod follow the spawning capelin (Mallotus villosus) inshore along the east coast of Newfoundland in late June and early July. They are traditionally fished with traps and handlines along this coast, but there has been a recent trend toward using drift nets set on the bottom. Since alcids feed extensively on capelin at this time, many are caught in the cod nets set in areas close to the large colonies off Witless Bay (D. N. Nettleship, personal communication). Additionally, gill nets are set at the surface for salmon in the same area. Common murres (Uria aalge) are most affected, but Atlantic puffins (Fratercula arctica) are also taken.
There are as yet no estimates of the total alcid mortality from this fishery, although the annual catch of birds is believed to be smaller during the present than during the last decade because the fishing effort is reduced, and fishermen in the area now avoid setting nets near alcid concentrations because of the annoyance of having to remove the birds from their nets. The Witless Bay colonies contain over 77,000 pairs of common murres, or 11% of the total eastern North American population, and over 235,000 pairs of Atlantic puffins, or 71% of the North American population outside of Greenland (Brown et al. 1975). The potential danger is obvious.
There are few data on mortality of seabirds from inshore commercial fisheries in the North Pacific. Some mortality of alcids has been shown to take place in Cook Inlet, Alaska, from beach-netting for Pacific salmon (Oncorhynchus spp.) adjacent to seabird rookeries and from drift-netting in the inlet (D. A. Snarski, personal communication), but this mortality has not been quantified.
Bilateral agreements between the United States and Japan, the U.S.S.R. and the Republic of Korea, concerning the use of inshore waters adjacent to some of the Aleutian Islands, Kodiak, Nunivak, St. Matthew, St. George, Kayak, and Forrester Islands permit trawling, longlining, and loading fish and fuel in some of these areas and at certain periods. Although these activities may affect the seabirds of these areas, the extent of the effects are not known (U.S. Department of the Interior, Alaska Planning Group 1974). Murie (1959) indicated, however, that the disappearance of the ancient murrelet (Synthliboramphus antiquus) from Sanak Island, Gulf of Alaska, was probably due as much to fisheries as to the blue fox industry. It has been suggested that the Japanese murrelet (Synthliboramphus wumizusumi) may have declined as the result of fishing activities near breeding sites off the coast of Japan (Bourne 1971).