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15 <br />containers maintained at ambient lake temperature (15.0-17.0°C). Fish <br />were starved 48 hours to allow evacuation of guts and 10 razorback <br />sucker larvae were introduced to each jar. All were consumed within <br />0.25 hours. Sunfish were then sacrificed and dissected at 2-hr <br />intervals. <br />At 2 hrs after ingestion, larvae appeared as whole individuals <br />readily identified as razorback sucker, although fins were slightly <br />eroded and body shape distorted. At 4 hrs, larvae were digested into <br />amorphous masses of flesh beyond specific identification; individuals <br />retained only enough integrity to be accurately enumerated (N = 10). <br />After 6-hrs of digestion larvae were no longer distinguishable - only 12 <br />eye lenses remained of the 20 originally present - others had been <br />digested beyond recognition or defecated. Larvae were undetectable <br />after 8 hrs - not even lens tissue remained which could be so <br />identified. <br />This simple, short-term experiment will be refined, expanded, and <br />repeated. Until confirming data are available, results of previous <br />studies, including our own, of potential predation on larval razorback <br />sucker should be viewed with caution. A sampling regime where potential <br />predators are preserved or dissected immediately after capture will be <br />necessary to adequately evaluate impacts of predation. In the case of <br />threadfin shad, biochemical techniques may be required to adequately <br />assess predation; because of their gizzard-like foregut, stomach <br />contents are usually well masticated and difficult to identify (Burns <br />1966).