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Endangered Fish Rearing Facilities


The Hualapai Tribe has constructed, with HDNR, an Endangered Fish Rearing Facility on the Hualapai Reservation in northwestern Arizona. The facility was built on approximately 80 acres and in the future will consist of eight concrete raceways, eight brood ponds, four nurse ponds, twelve rearing ponds, one holding pond, a reticulation system, employee housing, maintenance and laboratory buildings.

Endangered Fish Facility


The Hualapai Department of Natural Resources, in its fish rearing management practices follows the same guidelines in use by  U.S. Fish and Wildlife Service and Arizona Game and Fish Department.  The Hualapai Tribe works in cooperation with the U.S. Fish and Wildlife and Arizona Game an Fish to establishing a refuge population of endangered Grand Canyon Humpback Chub (Gila cypha) on the Hualapai Reservation to protect the species against future loss in its primary habitat in the Little Colorado River (LCR).

The Hualapai refuge population will serve as a source of wild Grand Canyon humpback chub that will be available for either broodstock or release back into the river or it tributaries if needed to sustain the Grand Canyon population of humpback chub.  Until such a need arises, all humpback chub at the Hualapai Facility will only be held.

Recovery planning for the endangered humpback chub includes the potential for captive holding and assurance population development (U.S. Fish and Wildlife). The Endangered Species Act defines management action and tasks necessary for the development of captive assurance populations, as well as for their use in a captive breeding and stocking program should the need arise. The purpose of establishing assurance populations is to develop and maintain representative captive stocks to ensure the retention of the genetic diversity present in the Lower Colorado River Basin in the event of a catastrophic decline in the wild population.  Tanslocations are intended to expand the demographic range of humpback chub in Grand Canyon and to provide warmer, lower predator rearing areas in tributaries.  To accomplish that goal, a strategy is provided to maintain gene flow from the wild population to the captive and translocated stock to counter the effects of evolutionary processes and stochastic genetic changes known to occur in fish populations.


The Hualapai fish facility does address the immediate need for a rearing facility for razorback suckers, (Xyrauchan texanus) and other endangered and/or native species for reintroduction into tribal and non tribal waters. The Hualapai Reservation is an ideal location for the facility because of it's proximity to the Grand Canyon and due to the available resources the Reservation can provide, namely land and water.

The Hualapai Tribe has an agreement with the Arizona Fishery Resources Office to raise native fish at he Hualapai Native Fish Hatchery.  The Hualapai Department of Natural Resources agrees to maintain and 5000 Razorback Sucker fingerlings. 

Tribal Responsibilities include:

  1. Maintain the ponds to optimize growth of fish

  2. Feed the fish with food provided by USFWS at a rate of 1% of their body weight/day, adjusted monthly

  3. General monitoring (visual) for disease

  4. Report any problems (i.e. die off or disease outbreak) to AZFRO-Parker

  5. Control vegetation in ponds

  6. Coordinate pond collection in summer to determine fish condition

In 1999 the Hualapai fish facility received 5000 fish and again in 2006 5000 Razorback Sucker fish were received.  All fish are held in the fish rearing facility until harvested by the Arizona Game and Fish Department for studies and release.  Fish harvested have an average of 358 mm in length and average weight of 418 g.


On November 6, 2007 staff from the Dexter Fish Health Unit examined 30 Razorback Suckers from the Hualapai Tribe's Fish Facility.  The fish were examined to determine if there were any pathogens of concern in the population of Razorback Sucker fish cultured at the facility.  Each Razorback Sucker was examined for viruses, bacteria, external and internal parasites. 

No viruses or bacteria targeted by routine inspection protocols were isolated that would preclude any fish transfers or relocations.  No external or internal parasites including Asian tapeworms were present in the Razorback Sucker fish.  Asian tapeworms were looked for at the request of USFWS's Arizona Fish and Wildlife Conservation Office.


The construction of Glen Canyon Dam and it's subsequent operation have contributed to the decline of the native fishes of the Colorado River in the Grand Canyon (Minckley and Deacon 1991). Only four of the eight species that occurred in predam times remain as viable populations. A fifth, the razorback sucker, is still abundant in Lake Mohave, but it's population is declining. In 1990 the population estimates in Lake Mohave totaled 60,000 and today that estimate has declined to nearly 25,000 (Burke 1994). The altered water temperature regime, daily discharge fluctuations and the presence of introduced fishes are believed to be responsible for the decline of the native fish fauna. At this time, the Final Glen Canyon Dam Environmental Impact Statement (FGCDEIS) is proposing to reduce daily discharge fluctuations and to study how the modification of dam operations might allow for warming of Colorado River water to enhance native fish populations.

The status of threatened and native fishes of the Colorado River through the Grand Canyon have been the subject of increasing concern during the present FGCDEIS and subsequent Final Biological Opinion and Reasonable and Prudent Alternative developed by the U.S. Fish and Wildlife Service (Service). Both documents contain elements that address the need to establish a second population of the endangered humpback chub, Gila cypha and to design and implement plans to recover the endangered razorback sucker, Xyrauchen texanus in the Grand Canyon.

Presently, only one facility in the Southwest, Dexter National Fish Hatchery and Training Center (DNFHTC), is fully dedicated to rearing endangered fishes. Johnson and Jensen (1991), however, expressed a need for additional facilities to rear and maintain native fish populations.


Management strategies to mitigate genetic risks are followed to ensure the retention of extant genetic diversity.  Genetic risks that are addressed, as per the Propagation Policy (U.S. Fish and Wildlife), include; broodstock mining, inbreeding and inbreeding depression, population homogenization, domestication selection, hybridization, and outbreeding.  In addition, strategies to mitigate known risk factors associated with captive assurance population and propagation are addressed.  These risks include; genetic drift, flounder effect, which occurs when a new population is started from a few individuals and by chance the genetic constituency does not reflect the normal distribution of alleles in the donor population; and the Ryman-Laikre effect, which is an anthropogenic impact on the genetics of a wild population as a result of augmentation stocking.



Endangered Fish Facility

The proposed Hualapai facility would provide a state of the art fish rearing system to enhance the potential for future recovery of endangered southwestern fishes. It is also wise to have more than one facility raising these fishes to maintain genetic diversity in the species and to safeguard against catastrophic losses due to accidents.


Endangered Fish Facility


1. To rear razorback suckers and other threatened and/or native fishes for reintroduction into

mainstream Colorado River and/or it's tributaries on Hualapai Tribal Lands and other sites within the historic range of the species.

2. Provide economic development and education for the Hualapai Tribe by providing employment and training in fish rearing and aquatic biology for students at the facility.



1. Razorback suckers and/or other native fishes greater than 300mm available for stocking into waters of their historic range.

2. Employment, education and training for Hualapai and non  Hualapai individuals.

Current state of the Fish Facility.

*The 2.5 acre pond and 8- acre ponds are lined and plumbed with air and water.

*The reticulation system is functional and able to push 200 gal/min.

*One 100' raceway is functional.

*2- acre ponds have Razorbacks

Endangered Fish


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