Data are presented from gut content analysis of 94 Awaous
stamineus (Edouyx & Souleyet) ('o'opu nakea) collected from the Wainiha River
on the north shore of the Hawaiian island of Kaua'i during the period from June
1990 to May 1991. Also presented are results from gut analysis of 11 preserved
museum specimens captured in La'iemalo'o stream, O'ahu, in February 1938
and June 1939. The results suggest that introductions of alien insects into the
Hawaiian biota are changing the diet of this endemic fish. Comparison with the
results of an earlier study indicate that A. stamineus is still dependent primarily
on freshwater algae in the genera Cladophora, Rhizoclonium, Oedogonium, and
Spirogyra; however, aquatic insect foods in the diet have increased from about
6% to nearly 13% in the current study. The findings suggest a reduced reliance
on native aquatic chironomids in the genera Calospectra and Telmatogeton and
an increased selection of immature stages of several recent aquatic insect
immigrants, most notably two alien caddisfly species, Cheumatopsyche analis
(Banks) (Tricoptera: Hydropsychidae) and Hydroptila arctia Ross (Tricoptera:
Hydroptilidae), first reported in Hawai'i in 1967 and 1971, respectively
