| Abstract/Description or Keywords |
Adult trout migration in the Hill Creek spawning channel was monitored in 2007 by a three channel “Crump weir “ style resistivity counter. The fish counter collected contiguous data from April 20th through June 25th, except for one period on June 3rd of about 10 hours when power was lost from the site. A total of 334 upstream migrant fish and 274 downstream migrants were recorded by the fish counter between April 20th and June 11th. Total escapement was estimated as be in the range of 107 to 334 spawners dependant on recycling rates. Crump weir sensors indicated a weak relationship between peak signal size as described by the counter and fish length, based on video records (n=28). Utilizing this data for upstream migrants, fish over 50cm in fork length, represented approximately 201 or 60% of the total observed up migrant counts. Confidence limits cannot be placed on these data as yet due to a poor relationship between downstream migrant size and peek signal strength. Peak migration of all upstream fish occurred between April 28th and June 3rd. Larger migrants (>50cm) exhibited a more restricted migration timing, with peak observations between April 28th and May 19th. Greatest daily upstream movement was 20 large migrants recorded on May 5th. No obvious delays in migration were apparent, and there were no major periods of debris build on the counter. Video records were restricted due to fish migrating at night when cameras were not operational and due to power supply issues at this remote site. |
