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~ \1-. e e 8 but "this is probably more a reflection of nets being more effective in those areas. The four spa\ming sites located 1n the St. Joe River were in the lower fastwater bE~tween 40 and 52 miles above the river's mouth. In all four sites the common denominators were a substrate of large gravel small rubble 3 to 15 cm in diameter and free of sand and silt and a low water velocity near the substrate. In the one spawning site mapped bottom velocities where eggs were deposited were almost universally less than 1.0 ft per second. DE!pth was apparently of only secondary consideration and average depths at the 4 sites were approximately 2.0, 1.5, 3.0 and 8.0 m. Combinations of the appropriate substrate and bottom velocities are atypical in the St. Joe River. In most areas of low velocity considerable deposftion occurs and the substrate consists of fine material. Where the substrate is free of fines, velocities are too great for squawfish to hold positions. This n~y account for the low number of areas used by squawfish for spawning in the river. All four spawning sites were associated with braids in the river channel. Two were located where channels met below an island and two were in pool-like eddies in side channels where shelves at the head of the pool directed high velocity flows along the surface. In the Clearwater River, the one spawning site located was 9 miles above its mouth. The substrate at the site was gravel 3 to 10 cm in diameter which was free of sand to 10 em below-the substrate surface. The site was in a dished out area in a braided area where three side channels joined. Average depth was approximately 1 m. Northern squawfish were observed to spawn in large aggregations in both the St. Joe and Clearwater rivers. At one site in the St. Joe River where extensive observations were made, an estimated 3000 spawners were gathered 1n '\ a pool 10 m wide. IS m long and 2 m deep. Males outnumbered females by an