Awaous guamensis (Valenciennes 1837)

Adults move downstream to their prime breeding just above the estuary; males select crevices and caves formed by rocks on the stream bed where the females will lay their eggs; males guard nests until larvae hatch a day later (Ref. 44091).

Amphidromous. Refers to fishes that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.Characteristic elements in amphidromy are: reproduction in fresh water, passage to sea by newly hatched larvae, a period of feeding and growing at sea usually a few months long, return to fresh water of well-grown juveniles, a further period of feeding and growing in fresh water, followed by reproduction there (Ref. 82692).

Is an opportunistic feeder, takes aquatic and occasionally benthic terrestrial invertebrates when these are available (Ref. 7416). Occurs in streams, rivers and estuaries.

Benthic (Ref. 58302). Adults occur from lowland streams and rivers to relatively swift streams at elevations of 1000 m. They often burrow into the substrate with only the eyes showing; feed on filamentous algae, worms, crustaceans, various insects and insects larvae, and suspended food particles; has been long favored as food by the early Hawaiians (Ref. 44091). Larvae develop and metamorphose in the marine zooplankton and as juveniles, about 161 days old, recruit to freshwater streams, where they undergo rapid growth and morphological changes necessary for upstream migration to the adult habitat (Ref. 51037).