Two Variations of a Salmonid Smolt Trap for Small Rivers

Abstract

Trap nets were designed and constructed to capture steelhead smolts (Salmo gairdneri) that had been stocked as fry in two coastal streams of British Columbia. The traps were fabricated from knotless nylon netting material and had a horizontal screening section to cope with fluctuations in water flow and debris. The nets were suspended from cables from which they could be detached easily for cleaning or during extreme flows. The trap nets were used in flows of approximately 2.4 to 18.0 m 3/s on Lynn Creek and from 3.4 to 14.0 m 3/s on the Englishman River. Both nets remained operational at flows of approximately 10 m 3/s. In efficiency tests, 78.1 and 54.7% of the steelhead smolts released above the trap nets were captured in the Lynn Creek and the Englishman River traps, respectively. The nets were an effective and inexpensive means of fishing these streams. They provide an easily cleaned, large screening area and can be modified for other locations.