Evaluation of a gastric lavage method for use on largemouth bass

The efficiency and delayed mortality caused by a new gastric lavage device was evaluated for use on largemouth bass Micropterits salmoides. A 12-V electric pump was specially fitted to flush stomach contents from largemouth bass larger than 200 mm. The device was easily operated by a single person and removed more than 90% of stomach contents. The lavage technique caused no immediate mortality of largernouth bass. Delayed (7-d) mortality of largemouth bass undergoing gastric lavage was not significantly different from that of controls. Further, mortality did not vary significantly with body length. Overall, the technique appears to be a viable method for rapidly collecting stomach contents from a broad size range of largemouth bass while causing minimal initial and delayed mortality.