An endangered fish species has been observed to be spawning in the lower Colorado River.
Razorback suckers (Xyrauchen texanus) were believed to have been missing from the Grand Canyon since the 1990s, but researchers have detected larvae where they have not been seen in about two decades, a U.S. Department of the Interior news release reported.
"The discovery that the Razorback suckers are spawning in the national park far upstream from Lake Mead is good news for this endangered species," Assistant Secretary for Water and Science Anne Castle, said in the news release. "It is also a demonstration of the power of the partnership among Interior's Bureau of Reclamation, National Park Service, U.S. Fish and Wildlife Service and U.S. Geological Survey, who have worked for recovery of this species side-by-side with Arizona state officials, Indian tribes, private landowners and researchers."
The Colorado River and its tributaries were once highly populated with Razorback suckers. Alterations of the species' habitat, especially the introduction of nonnative species, confined spawning to only the Lake Mead National Recreation Area.
On March 16 2014 the National Park Service and Bureau of Reclamation released nine adult Razorback suckers into the Colorado River inside of the Grand Canyon National Park.
During an April monitoring trip researchers observed a number of newly and previously released sonic-tagged fish that had migrated upstream from Lake Mead.
"The most surprising result was finding larval Razorback suckers at nine of the 47 locations in the park - far upstream from Lake Mead," said Mark McKinstry, biologist with the Bureau of Reclamation.
The finding highlights the fish's ability to adapt to changing conditions.
"Razorback suckers continue to surprise us in Grand Canyon, first with the discovery of adults after 20 years of absence, and now with spawning within the park. We're all hoping to see evidence that these larval fish survive to adulthood in the coming years," Brian Healy, fisheries program manager for the national park, said in the news release.
"This exciting news suggests that Grand Canyon is becoming a significant basin-wide haven for the endangered fishes in the Colorado River," Lesley Fitzpatrick, biologist for the U.S. Fish and Wildlife Service, said in the news release.
