Ptychocheilus.--There are 2 species of Ptychocheilus in coastal streams of Oregon and Washington: Northern
Pikeminnow (P.
Bestgen and Bundy (1998) reported that increments deposited on the sagittae of Colorado
pikeminnow (Ptychocheilus lucius) were difficult to distinguish after the fish were 30 days old.
Similar to humpback chub and bonytail, voltage gradients <1.00 V/cm resulted in immobilization of rainbow trout, Oncorhynchus mykiss, (0.22 and 0.32 V/cm) and Colorado
pikeminnow, Ptychocheilus lucius, (0.63 and 0.20 V/cm) using pulse frequencies of 15 and 60 Hz, respectively, in ambient water conductivity of 530 [micro]S/cm (Meismer, 1999).
Predation and competition by nonnative fishes threatens the survival of these native species--their presence in the basin has been particularly damaging to the federally endangered bonytail (Gila elegans), humpback chub (Gila elegans), Colorado
pikeminnow (Ptychocheilus lucius), and razorback sucker (Xyrauchen texanus).
He was fishing for squawfish otherwise known by its new politically correct name, the northern
pikeminnow.
The state Department of Environmental Quality in 2008 and 2009 sampled tissue from northern
pikeminnow and large-scale sucker that were found swimming near the mouth of the McKenzie in the Springfield area.
This "river dance" helps establish new streamside forests, wetlands, and sandy beaches, as well as shallows that support species like the endangered Colorado
pikeminnow and razorback sucker.
Fish extinctions (e.g., Snake River sucker Chasmistes muriei) and extirpations (e.g., Colorado
pikeminnow Ptychocheilus lucius from the lower Colorado River) in North America are most numerous in the West where reservoir construction, non-native fish introductions and water withdrawals altered habitat and established new predators and competitors for native fishes (Minckley and Douglas, 1991).
These changes contributed to the decline of the razorback sucker and three other fish species that exist nowhere else on earth: the humpback chub (Gila cypha), bonytail (Gila elegans), and Colorado
pikeminnow (Ptychocheilus lucius).
Luecke predicts Million's project will cause difficulty in protecting populations of the Colorado
pikeminnow, an endangered species in the upper Colorado River Basin.