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Hubert and Patton: Fish Catches with Hoop Nets 3 METHODS p We used hoop nets with two designs: metal-framed D nets and wood-framed round nets. The D nets consisted of seven hoops; the first hoop was D-shaped and 1 m in width, and remaining hoops were round and 0.7 m in diameter. The mesh size was 3.8 cm (bar measure) between the first and second hoops and 2.5 cm on the remaining hoops. Round nets were made with seven hoops; the frrst was 0.75 m in diameter, and remaining hoops decreased progressively to 0.6 m at the cod end. The netting was 5.0 cm at the open end and decreased to 2.5 cm at the cod end. Both types of hoop nets had square throats attached to the second hoop and a finger throat on the fourth hoop. We sampled at eight sites from 28 May to 19 August 1991 and from 13 May to 20 August 1992 (Fig 1). Two D nets and one round net were placed in the thalweg at each site. A steel rod was driven into the streambed, and nets were attached with a 5-10-m length of rope. Nets were placed 20-50 m apart in random sequence. The position of the round net among the three nets was random in order to avoid possible location effects. The content of each net was removed and identified two to three times weekly. Nets that were collapsed or had holes in them upon retrieval were not included in the sample. Nets were slightly relocated at some sites as the flow declined to keep them submerged. Catch per unit effort was recorded as the number of each fish species captured per net-night. Total length was measured on all fish captured in 1991 to make assessment of possible size selectivity with the two net types. The frequency distributions of CPUE were not nonnally distributed, and a rank ttansfonnation was made on all distributions. Variation in CPUE between the two types of nets, between sampling years, among sampling sites, and among sampling months was assessed for the six most abundant species as well as the total catch of all species. Two-sample comparisons of CPUE were made with two- sample t-tests, and multiple comparisons were made with one-way analysis of variance (Sokal and Rohlf 1981). Length distribution of fish captured in the two types of nets were assessed for differences using a two-sample t-test. Chi-square goodness-of-fit tests were used to assess differences in species composition between net types and sampling years. Analyses were made with STATISTIX 3.1 (Analytical software 1990). Significance was accepted at P:5; 0.05 in all tests. RESULTS A total of 575 fish was captured during 1712 net-nights in 1991 and 978 fish during 2126 net-nights in 1992. In 1991, we captured 382 fish (66% of total fish) with the D nets during 1204 net-nights (70% of total effort) and 165 fish with the round nets during 508 net-nights. In 1992, we captured 578 fish (59% oftotal fish) with the D nets during 1444 net-nights (68% of total effort) and 400 fish with the round nets during 682 net -nights. In 1991, the mean CPUE did not differ by type of