A series of stone dams, usually four, were constructed along some shallow spot in a river. The lower dams had narrow gaps through which migrating fish could pass. The upper dam, however, blocked the river completely and the trapped fish proved easy prey for the Copper Eskimo. G.H. Wilkins, the photographer for the Canadian Arctic Expedition, described a fishing venture at Nulahugyuk Creek near Bernard Harbour in 1915:
The men and sometimes the women would run into the water with their spears and jab and poke at the fish as they swam around. Some of the women would run to the walls of the weir and catch the fish as they stuck in between the stones in their attempts to get away. By this method the fish would soon get thinned out and there would be great competition for the remaining few. Eight or ten people would sometimes be spearing for the same fish with the result that some one or other's toe would suffer. I never saw any argument as the result of this, but the injured one would retire from the fray for a moment or so and rub his toe. Soon the possibility of getting the fish would induce him to try for it between the other people's legs, with the frequent result that another would be delayed for a minute or so to rub his toe or shin. All the knocks were taken good-naturedly and they would discuss their injuries after the fray without any sign of ill feeling. When a fish was caught either by the men or women, they would run it through with a bone needle threaded on a string with a cross piece at the end and drag the fish about with them in their endeavours to secure another one. Sometimes when the pond was almost cleaned out they would stop to kill the fish by knocking it on the head with a stone picked up from the river bed before threading it on the line.
