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III). Identify light trap and drift net samples. Ongoing. Middle Green River ligbt trap samples. A total of95 light trap and seine samples were collected in 2002. Seine samples were collected this year because low water limited locations available for light trap sampling. Cliff Creek, Jensen Bridge, Greasewood Corral, Old Charlie Wash outlet, and Shepard Bottom outlet were among the sample sites in 2002. The first catostomid larvae, a single Catastamus lalipinnis, was collected on 15 May at Cliff Creek. The first razorback sucker larvae detected was on 20 May at that same location. Preliminary identifications have been made on about half of the samples; sample identification should be complete in early 2003. Lower Vampa River drift net sampling. Samples were collected in the Yampa River about 0.8 km upstream from the Green River, the same site that samples were collected at from 1990 to 1996 (Bestgen et a1. 1998) and in 1998 to 2001. A total of207 samples were collected between 18 June and 4 August 2001. These included samples collected at dawn, noon, dusk, and midnight on approximately weekly intervals on seven occasions to detect die! variation in drift abundance. Preliminary identification of samples has just begun so few results are available. We did detect drifting pikeminnow larvae as early as 26 June, well after planned high spring flow releases from Flaming Gorge Dam ceased. Reproductive success of Colorado pikeminnow was considered moderate in 2001, and perhaps similar to 1999 and 1998, when 685 and 716 pikeminnow larvae were collected, respectively. The total number of fish captured inI998 and 1999 were substantially higher than previous years from 1991 to 1997. In summer 2002, flows were very low and clear, conditions similar to 1994 when Colorado pikeminnow drift net captures were very low. 2001 light trap sampling data. Only preliminary data were available from 2001 light trap samples at the time of the December 2001 report deadline so we present that data now. A total of 4,046 specimens were captured in nine species in 2001 (Table 1). A total of 92 razorback sucker larvae (including 2 I specimens classified as razorback sucker?) were captured and represented 2.3 % of all fish captured. Larvae were captured from 23 May to 18 June when average daily water temperatures was increasing slowly and in the 14 to 18'C range (Fig. 1). Larvae ranged in size from 11 to 16 mm TL; most were II to 12 mm TL (Fig. 2). The largest 15 and 16 rom TL larvae were captured later in the season on or after 29 May (Fig. 3). All larvae were captured after discharge in the Green River peaked on 18 May at 14,400 cfs. The proportion of razorback suckers in 2001 middle Green River light trap samples compares favorably with proportions and catch rates from samples FY 2002 Annual Report 22fPage - 4