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salmonid
06-25-2014, 07:26 PM
Crazy that fish can survive in the desert. We are working on a project to study these rare fish now.

They live in a single water pool that seems to be shrinking perhaps due to water withdrawals. Their species range is probably the smallest of any animal species? Just one cave with water in it. I had never heard of them before, but they are cool desert survivors for sure.

Here is a link... Devils Hole Pupfish Home Page (http://www.fws.gov/nevada/protected_species/fish/species/dhp/dhp.html)

Updated November 2013... The Devils Hole pupfish (Cyprinodon diabolis) was listed as endangered in 1967. This iridescent blue inch-long fish's only natural habitat is in the 93 degree waters of Devils Hole, located within the Ash Meadows National Wildlife Refuge (http://www.fws.gov/refuge/ash_meadows/), Nye County, Nevada, which is a detached unit of Death Valley National Park.


http://www.fws.gov/nevada/protected_species/fish/species/images/dhp_location_map.gif (http://www.fws.gov/nevada/protected_species/fish/species/images/dhp_gallery/devils_hole/low_res/dh_location.jpg)A count in April 2013, estimated 35 Devils Hole pupfish remain in their natural habitat. A September count estimated 65 fish. These record low spring and fall counts indicate that this small, inch-long, iridescent blue fish could now be at significant risk of extinction.


A Harsh Environment

Devils Hole pupfish is one of the world’s rarest fishes, spending most of its life in the top 80 feet of the 93 degree waters of cavern in the middle of the Mojave Desert. Its habitat is one of the smallest natural ranges known for any vertebrate.

Devils Hole is an extreme environment, with water temperatures and dissolved oxygen concentrations near their lethal limits for fish. It is thought this fish has survived and adapted to these harsh conditions for thousands of years.

Although the surface of the Devils Hole pool is small, it is an aquifer over 400 feet deep that is linked to groundwater important to Nevada and California. Scientist have recently discovered a connection with Devils Hole to earthquakes thousands of miles away. In 2012, violent pressure waves (mini-tsunami) were recorded in Devils Hole as a result of earthquakes as far away as El Salvador and Mexico.

The Downward Trend

Endemic species with limited distribution like the Devils Hole pupfish are at greatest risk of extinction since they do not have the flexibility to change locations to adapt to changing environments.

This short-lived species (approximately one year) has a natural high and low cycle, with the population in the fall decreasing from 35-65 percent in the spring due to natural die-off. When population counts began in 1972 pupfish numbered around 550 individuals.

From the late1970’s through 1996, the population appeared to be relatively stable with an average count of 324 individuals. In 1997, fall counts started to indicate a downward trend for unknown reasons. The number of pupfish counted from 1997 to 2004 declined from an average of 275 individuals to 171 fish. A count conducted in November 2005 indicated 84 individuals, and an April 2006 count of only 38 adult pupfish, the lowest count on record at that time. A dive into Devils Hole in September 2006 resulted in 85 adult pupfish indicating they were recruiting and reproducing in their natural environment.

Over the next six years the number of pupfish initially increased to 126 fish as supplemental feeding began, but has since declined again. The September 2012 count of Devils Hole pupfish determined the number of pupfish had dropped to an estimated 75 fish followed by the spring 2013 count that resulted in an all-time low count of 35 fish.

The lowest fall count on record of 65 fish occurred in the fall 2013. This fall count is predicted to drop in spring of 2014 by 35-65 percent, consistent with the species population trends, bringing Devils Hole pupfish even closer to extinction.

The reason(s) for the decline of Devils Hole pupfish is unclear. The environment in Devils Hole has changed in a variety of ways, some of which scientists do not fully understand. Although the Devils Hole environment is small, changes can be subtle and complex, making it difficult to identify specific factors influencing the fish’s population from year to year.

and more... Devils Hole Pupfish Home Page (http://www.fws.gov/nevada/protected_species/fish/species/dhp/dhp.html)

JoeReal
06-26-2014, 07:08 AM
Were there any attempts to culture and multiply the fish outside of their natural habitat? It would be interesting endeavor. I would assume that it would be easier for fish to survive in a less hostile environment compared to their literal hell hole called home. Who knows if they really need to be in such environment to survive when no other fish can, thus having no competition. A fish that can survive extreme conditions should be tested in a controlled environment to unravel the factors contributing to their survival or demise, and we may learn more on what it takes to survive the kinds of environment they are living.

salmonid
06-26-2014, 07:14 AM
Were there any attempts to culture and multiply the fish outside of their natural habitat?

Yes, they are trying that now. The folks working there got some fertilized eggs and some of them hatched.

JoeReal
06-26-2014, 07:30 AM
Yes, they are trying that now. The folks working there got some fertilized eggs and some of them hatched.

I haven't read that much article about them although the fish was discovered long before they were listed as endangered in 1967. IIRC, one of my classmates used to study them during the early 1990's.

OYD
06-26-2014, 07:56 AM
My wife and I have visited them a few times but it must be almost 10 years since our last visit. They were still doing fine at that time but a lot can change in a 10 year period. I hope they continue to hang on.

JoeReal
06-26-2014, 08:22 AM
My wife and I have visited them a few times but it must be almost 10 years since our last visit. They were still doing fine at that time but a lot can change in a 10 year period. I hope they continue to hang on.

Our weather patterns are rapidly changing during the last two decades, and with the drought stress, it doesn't look good for these pups.

YUBADUBA
06-26-2014, 06:26 PM
So can we use pupfish for striper bait? They look killer! Haha

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salmonid
06-26-2014, 06:33 PM
At one inch long, they probably would only be good for schoolie or shaker striper?

But on another note, if we can't give more water to fish there are gonna be lots more species on the endangered list!

Best,


So can we use pupfish for striper bait? They look killer! Haha