. Fish populations of the wild & scenic Missouri River, Montana . Fishing surveys; Wild and scenic rivers; Fishes; Fishes. gravel or sand and gravel substrate at the head of the larger pools in water at least m (5 ft.) deep. Nets placed on unstable substrate, such as sand or mud, usually resulted in poor catches and often became partially buried and were difficult to retrieve. To facilitate feeding out of the bait the nets were placed in areas with current velocity as swift as possible without washing away the nets. The first nets set in each section were left in the water for 48 to 72
. Fish populations of the wild & scenic Missouri River, Montana . Fishing surveys; Wild and scenic rivers; Fishes; Fishes. gravel or sand and gravel substrate at the head of the larger pools in water at least m (5 ft.) deep. Nets placed on unstable substrate, such as sand or mud, usually resulted in poor catches and often became partially buried and were difficult to retrieve. To facilitate feeding out of the bait the nets were placed in areas with current velocity as swift as possible without washing away the nets. The first nets set in each section were left in the water for 48 to 72 hours to allow sufficient time for the bait to feed out. The nets were then raised and data on the catch recorded. After the first set, the nets were checked approximately once every 48 hours. Information on the time of setting and raising, correct to the nearest five minutes was recorded for each net. Frame Traps Spawning migrations of sauger and other species were monitored on the lower Marias River with m (3 ft.) high by m (4 ft.) long frame traps (Figure 6). The traps were constructed from cm (1 in.) square mesh fence wire and cm (% in.) diameter reinforcing rod material. Similar traps were used successfully by Posewitz (1963) to capture fish in the middle Missouri River and the lower reaches of its (if •* Figure 6. Spawning migrations of sauger in the lower Marias River were monitored with frame traps. 12. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Berg, Rodney K; Montana. Dept. of Fish, Wildlife, and Parks. [Helena] : Montana Dept. of Fish, Wildlife & Parks
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Keywords: ., book, bookcentury1900, bookcollectionamericana, booksubjectfishes
