01 Department of Agriculture, Conservation and Forestry



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Tributaries.
Roach River
The following description of fish habitat in the Roach River is taken from the Roach River Strategic Plan for Fisheries Management prepared by IF&W in 1985.
First Roach Pond to Moosehead Lake. From its origin at the outlet of Third Roach Pond, the Roach River flows 19 miles (9 miles through Second Roach Pond and First Roach Pond) to Moosehead Lake. There are three geographically distinct sections to the Roach River. They will be described individually as follows: from the outlet of First Roach Pond to Moosehead Lake; from the outlet of Second Roach Pond to First Roach Pond, and from the outlet of Third Roach Pond to Second Roach Pond.
The section best known for its fishery and most important for its contribution to the natural reproduction of landlocked salmon and brook trout for Moosehead Lake is the 6.3-mile section below First Roach Pond. From the base of the dam at First Roach Pond to Moosehead lake at its normal pool elevation (1,029 feet), the Roach River drops approximately 190 feet, an average gradient of about 32 feet per mile. The river width varies from approximately 50 feet to 132 feet during normal flows, averaging 75 feet. However, when water covers the entire river bed, the average width is approximately 100 feet. The depth varies from about 1 to 6 feet during normal flows. The river flows through well-defined banks, once heavily forested. Except for narrow green-belts on either side of the river, the forest was clear-cut in the 1960's and early 1970's.
Approximately 90% of the river bottom consists of rock and boulder riffles providing excellent nursery areas for salmon and brook trout. The remaining 10% is small rocks, gravel, and sand; the rubble's coarseness is best suited for salmon spawning. The most extensive gravel area is located in the river's lowest 200 to 300 yards. Another major salmon spawning site is within the upper one-half-mile below the pool at the First roach Pond dam. There are scattered salmon and brook trout spawning sites among the larger rocks or at the edges of bars in the river's wider sections. There are few resting pools available for adult salmon and trout.
Two major tributaries enter this section of the Roach River. Jewett Brook enters less than 1 mile from Moosehead Lake. This small stream has some brook trout in the springy areas, but salmon spawning areas are not available and trout spawning areas are limited.
Lazy Tom Stream, entering approximately 1 mile below First Roach Pond, has spawning and nursery facilities available in the 2-mile section between the river and an old dam at the outlet of Lazy Tom Deadwater. The flowage was used to store pulpwood that was driven through the dam on high water and into the river. Bulldozed streamside landings and the pulpwood drives widened the stream and removed much of the bank and stream cover during the wood driving years. Recovery has been slow but the stream banks are again vegetated. Electrofishing has provided evidence that a limited number of salmon parr are again using Lazy Tom Stream as a nursery area.
A minimum flow of 75 cfs has been established for the Roach River from First Roach Pond to Moosehead. Lesser flows are injurious to aquatic insects and plant life so necessary for fish populations, destroy eggs of fish and insects, reduce the size of salmon and trout nursery areas, and make fish more vulnerable to preying birds and mammals.
In July 1971, the entire reach from First Roach Pond to Moosehead Lake was surveyed to evaluate its spawning and nursery suitability. Determination of spawning suitability was made based on visual comparisons of the river bottom to areas within the river where salmon spawning was known to occur annually. Since 1971, the two major areas deemed suitable for salmon spawning have been repeatedly visited during the subsequent spawning seasons and both spawning adults and redds have been observed. No attempt was made to calculate actual acreage of suitable spawning gravel. Nursery areas were rated based on visual comparison with area where salmon parr had historically been electrofished in significant numbers. Areas suitable for brook trout reproduction were noted when observed. At the time of the survey, the flow through the First Roach Pond dam was estimated at 50 cfs. Lazy Tom Stream contributed an additional estimated 10 cfs. A summary of field observations is given in Table 4. The widths shown in the table are of the wetted area of the river channel.
The total area of this section of the Roach River was calculated to estimate the amount of salmon nursery area available. Measurements were made from aerial photographs (scale 1:15,840 or 4 inches to the mile) obtained from Scott Paper Company. The length was measured, using a map measurer, three times and the results averaged. Also from the aerial photos, twenty measurements of width were made and the mean calculated. The potential nursery area on the Roach River from the dam at First Roach Pond to Moosehead Lake is 2,502 units (one habitat unit equals 100 square yards). Estimates of parr abundance have been made using standard electrofishing techniques. The area sampled is, on appearance, typical of most of the river that was rated as "very good" nursery habitat. The two most recent estimates were made in August 1978 and 1979 (4.68 parr and 5.12 parr per habitat unit. Based on these estimates the total potential parr production for the roach River might average 12,250 per year. Using observations made by biologists equipped with SCUBA gear who floated sections of the river counting salmon parr, and estimates based on electrofishing done prior to 1978, the actual number of parr per habitat unit may be as high as 7.0. AuClair chose to use 7.0 parr per unit to determine potential production for the Roach River.7 The resulting estimate was approximately 17,500 salmon parr, approximately one-half of the total estimated parr production from all of the Moosehead Lake tributaries.




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