An oriental weatherfish (Misgurnus anguillicaudatus) population established in Washington state

The objective of this paper was to present some preliminary life history ob servations on a new exotic species, oriental weatherfish (Misgurnus anguill icaudatus), in the Lake Washington watershed of Washington State. During 19 99 electrofishing surveys of Lake Washington Ship Canal (Portage Bay, Lake Union, Fremont Cut, and Salmon Bay), 21 oriental weatherfish were collected . An additional 15 specimens were observed but not captured. Two additional oriental weatherfish were found in the stomach of a largemouth bass (Micro pterus salmoides). Oriental weatherfish were collected in areas that contai ned aquatic macrophytes and a mud/silt substrate. Most female oriental weat herfish were gravid. On average, females were considerably larger than male s. Only 7 of 19 oriental weatherfish contained prey. Chironomid larvae and pupae, amphipods, and cladocerans made up 96% of the diet by wet weight. Cl adocerans and chironomid larvae were the most frequently consumed prey. It is unclear what impact oriental weatherfish will have on the fish assemblag e in the Lake Washington Ship Canal. Since oriental weatherfish can withsta nd a wide range of environmental conditions, they may expand to many areas of the Lake Washington basin.