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The limited information available on larval razorback suckers and their inferred spawning dates <br />indicate watertemperature has an affect on timing. It is likely that razorback suckers spawn two <br />to four weelvearlier in the lower Green River than upstream. Spawning earlier on the hydrograph <br />m~t be beneficial if flooded habitats are critical for early life stage development /survival. ~; ~ ~'~~`- <br />C <br />~~ ~~~~ ~' <br />Colorado squawf-ash ~ t`{- <br />The results of this study indicate that Colorado squawfish did not spawn in the lower Green <br />River, near Millard Canyon in 1994. Concurrent sampling in late June 1994, in Desolation <br />Canyon .revealed large numbers of ripe male squawfish collected primarily with trammel nets. <br />Similar sampling conducted a week earlier at Nf~llard Canyon revealed none. Sampling for adults <br />at Millard Canyon in late June, 1995 may have been a bit pre-mature. Sampling in Desolation <br />Canyon occurred at the end of J~ , 1995 and again revealed good numbers of ripe male <br />squawfish. In other words the timing of Millard Canyon sampling was likely right in 1994 and <br />may have been early in 1995. <br />The early life history data collected during the subject study did not reveal any larval squawfish. <br />However, preliminary results from 1996 light trapping indicate some larval Colorado squawfish <br />were collected just downstream of Nfillard Canyon, at Anderson Bottom. Sizes ranged from 7.8 <br />mm to 10.2 mm indicating spawning may have occurred nearby. It is our feeling that if spawning <br />occurs at Millard Canyon it has likely dwindled to a very small population offish, particularly in <br />light of collection data at other known and suspected spawning areas. We discount this potential <br />spawning area with caution, based on our own experience sampling squawfish near suspected <br />spawning bars (Desolation Canyon studies). In Desolation Canyon we sample relatively short <br />stretches of river (0.5 mile on average} with six trammel nets. On several occasipns we have <br />handled more than ten fish in a night -with all the fish collected from one net. Wlhen these fish <br />congregate there seems to be specific habitats they occupy and paths they travel. The difference <br />between a strong catch offish and none is often contingent on the placement of one net. <br />DRAFT 17 <br />