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Triploid fish theoretically divert energy from sexual development and reproductive behavior into somatic growth. We found lengths, weights, and relative weights of triploid rainbow trout Oncorhynchus mykiss to be significantly (P < 0.05) less than those of diploid fish at the age of 45 months in three South Dakota ponds. Gonadal development in triploid females was negligible in 1989 and 1990 and reduced in triploid males during 1990. Catches of triploid fish were always lower than catches of diploid fish, suggesting lower survival. Physiological factors, perhaps environmentally induced, may have diminished the growth potential of triploid rainbow trout. Results of this study indicate that the use of triploid rainbow trout is not justified as a means of obtaining increased growth and survival under the conditions present in our study ponds.

Over the last 35 years there has been a shift in university wildlife and fisheries academic programs away from management and toward an ecology or conservation ethos. These university changes have been in both research and education. A similar change has occurred in direction among state and federal natural resource agencies. However, the changes exhibited by both groups have not been to the same degree. I believe university academic programs are now scaled more to the ecology—conservation side, while agencies still average to the management side. This represents a disconnect because university academic programs conduct research for these agencies (and others) and also educate future agency employees and provide technical services to agencies.

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A simple and rapid flow cytometric method of identifying triploidy in larval fish was developed. Prolarvae (4.6–8.0 mm total length) of walleye (Stizostedion vitreum) were mechanically dissociated into single‐cell suspensions and stained with the metachromatic fluorescent dye acridine orange. Dissociation of the prolarvae, application of a two‐step acridine orange staining procedure, and identification of ploidy level by flow cytometry was accomplished in under 10 min/sample. This procedure could be adapted for other fish species and could be used to identify other levels of polyploidy or mosaicism.