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Spawning behavior in Nocomis effusus is described from direct observations and review of videotapes made in Yellow Creek (Cumberland River drainage), Tennessee in 2003. Nest construction (i.e., excavating a concavity, forming a platform, and building a mound), and spawning behavior in N. effusus where a single breeding male excavates a pit and spawns with females on the upstream slope of his nest is like that described for Nocomis asper and Nocomis biguttatus. In digging a spawning pit, a male N. effusus reshapes and reorganizes substrate materials that results in spawning areas on the upstream slope of the nest composed of 6.0 and 11.3 mm size-class pebbles. Aggressive behaviors (in order of increasing aggression) observed between nest-building and intruder male N. effusus were non-contact head displacement, non-contact body displacement, chase, circle swim, and head/body butt. Nest associates (i.e., species that congregate and may spawn in a nest but do not contribute to its construction) observed over nests of N. effusus were Luxilus chrysocephalus and Lythrurus fasciolaris.