About Ptychocheilus oregonensis (Richardson, 1836)
Ptychocheilus oregonensis, commonly known as the Northern pikeminnow, Columbia River dace, or colloquially Squawfish, is a large member of the minnow family Leuciscidae. This predatory freshwater fish is native to northwestern North America, with its native range extending from the Nass River basin to the Columbia River basin. There is significant concern about the impact that Northern pikeminnow populations have on salmon in the impoundments of the Columbia and Snake Rivers. Northern pikeminnows can live for at least 11 years. They reach a maximum total length of 35 inches (89 cm) and a maximum weight of 15 pounds (6.8 kg). Females reach sexual maturity at approximately six years of age, while males reach sexual maturity between three and five years of age. A mature female can lay 30,000 eggs each year. Northern pikeminnows are skilled predators, and in the Columbia and Snake Rivers, salmon smolts make up a large portion of their diet. Their populations have grown substantially following the development of the Columbia River hydropower system, as the reservoirs created by the system provide excellent habitat for the species and give it an advantage over already depleted salmon and steelhead populations.
