Population, Conservation Status, Threats:
While Colorado pikeminnow were once abundant throughout the desert southwest, a combination of habitat loss, damming, introduction of nonnative fishes, and overharvesting caused populations to plummet. Now considered threated by the IUCN, their populations appear to be stable, and efforts to restore pikeminnow to their range are ongoing. They continue to face threats from invasive and nonnative species, dams and water diversion, and are likely to be impacted by climate change as water availability and use shifts with the climate.
Physical Description:
The Colorado pikeminnow is a species of large, toothless fish. They are long, with a wide head, generally resembling a pike - giving them the name pikeminnow. They are pale silver-green, with a lighter belly and darker fins.
Colorado pikeminnow range from the IUCN Red List. Extant populations are in yellow, areas where pikeminnow have been extirpated are in red.
Habitat:
Colorado pikeminnow live in medium to large rivers along the Colorado River basin. Young individuals prefer quiet backwaters, while larger adults make use of deep, fast waters, flooded lowlands, and sandy shoreline areas.
Behavior:
Pikeminnow occupy large home ranges, and may travel upwards of 200 miles between their home ranges and spawning areas.
Diet:
Pikeminnow are voracious predators, able to hunt even in muddy waters with poor visibility. While juveniles feed on small invertebrates, fish make up the majority of the adult pikeminnow's diet.
Reproduction:
Colorado pikeminnow spawn around midsummer, and their sticky eggs adhere to rocks along the riverbed, the fast-flowing water keeping them well-oxygenated. Once hatched, the young navigate to slow-flowing backwater nursery habitats to continue growing. Individuals reach sexual maturity at five to seven years of age, at which point they will establish home ranges in larger, faster-flowing waterways.
Associated Species:
Like the Colorado Pikeminnow, the razorback sucker, bonytail, and humpback chub are all large fish native to the Colorado River basin which have become endangered due to human impacts on the river.
Illustration by Willow Sedam