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) ~ ... Videography revealed spawning characteristics similar to those described by Minckley (1973, 1983). Fish, mostly males (80-90%), 'cruised' over the spawning area and often lay on the bottom presumably .l'~'aiting the arrival of ripe females. Typically, females attracted several males who would position their bodies against the females' posterior. Spawning occurs when the fish settled to the bottom and violently vibrated in unison for 2 to 4 sec. During this process, gametes were released, mixed, and driven into the interspaces of the gravel. The event caused considerable turbidity, which immediately attracted other razorback suckers that apparently fed on exposed eggs. Fish continued to feed in the area for 5 to 10 min, the period during which we assumed all exposed eggs were consumed. The density of spawning razorback suckers observed on the spawning site averaged 4.76 fishlm2 (range of 1.19 - 9.0; n=286). Based on the size of the area (90 m2) and the 2002 population estimate of 1,100 fish, this would suggest that nearly one third of the sucker population was typically in the spawning area. Razorback suckers would often lie quietly on the bottom in front of the camera. The species has the ability to roll and expose the reflective lining (sclera) of its eyes which causes a distinctive white reflection (photos 5 & 6). This unique peculiarity proved to be relatively common (n=>50). Its purpose, if any, is not understood, however, it is difficult to imagine such a distinctive display not having some purpose for such a highly camouflaged fish. Photos 5 & 6. A comparison of a razorback sucker "winking" and not winking its eyes. Bonytail. We did not witness any daytime schooling over spawning sites as we did last year. Bonytai1 were not seen from the bank or by snorkeling. Spawners were recorded by underwater videography during the second week of April. Fungused eggs were found between'the 8th of April and the 6th of May, which suggests spawning occurred during most of April when water temperatures ranged from 20.4 to 21.6 C (Figure 1). 9