Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006 Devils Hole Pupfish Recovery Action - July 18, 2006
Nevada Fish & Wildlife Office
Pacific Southwest Region
Devils Hole Pupfish Home | DHP Recovery Actions | Meetings and Events | Photo Gallery

Devils Hole Pupfish

Recovery Actions, July 18, 2006

Management decisions regarding conservation efforts for the Devils Hole pupfish were elevated to the Regional Directorate level of the Fish and Wildlife Service, National Park Service, and Director of the Nevada Department of Wildlife because of the continued decline of Devils Hole pupfish. These decisions have been carefully and deliberately discussed and debated prior to implementation. Full time staff from several agencies have been devoted to bring together expertise and establish emergency techniques to secure additional populations outside of the pupfish's natural habitat to prevent extinction.

Two propagation facilities have been established; one at Shark Reef at Mandalay Bay and another at Willow Beach National Fish Hatchery (Willow Beach NFH).

A hybridized pupfish, a cross of the Devils Hole pupfish and the Ash Meadows Amargosa pupfish from Point of Rocks Refuge, was used by biologists to establish transportation and propagation protocols for the pure strain of Devils Hole pupfish. In early May 2006, both of the new propagation facilities received 40 of these hybridized fish. Successful spawning and rearing of hybridized pupfish at both facilities is continuing.

In mid May 2006, two pure male Devils Hole pupfish were captured and transferred to Shark Reef at Mandalay Bay . Two pure female Devils Hole pupfish were transferred to that facility from Hoover Dam Refuge for breeding purposes. The pupfish were selected from the two populations in order to maintain genetic diversity.

Although the transfer and propagation of the hybridized pupfish has been successful, the transfer of the pure Devils Hole pupfish has been challenging. The pure Devils Hole pupfish did spawn, however, the eggs were not viable and both of the males died shortly after spawning. A decision was made to move two additional males from Hoover Dam and place them with the females since they appeared gravid. An additional loss of one of the females was reported in late June prior to being placed with the males. Biologists have not been able to determine the cause of the mortalities; these fish may have reached the end of their normal life span.

Devils Hole pupfish is a highly endemic species and only occurs naturally in one very small isolated system in the Mojave Desert . Narrow endemic species like the Devils Hole pupfish are at greatest risk of extinction since they do not have the flexibility to change locations or adapt to changing environments. Conservation biology principles suggest that small populations may not be capable of genetically maintaining themselves over a long period of time (i.e., may not be able to overcome the loss of genetic variability without human intervention).

Managers are now in a situation that can be compared to the of the California condor. They will be using a Structured Decision Making Process to determine all future Devils Hole pupfish conservation actions.

Agencies know that reversing the downward trend of Devils Hole pupfish will be difficult. The situation is compounded by the low numbers, skewed sex ratio, short lifespan of the Devils Hole pupfish, limited genetic diversity, and the difficulty of rearing them in captivity.

 

Last updated: September 28, 2012