Why is the Devils Hole Pupfish in danger of extinction?
"We really just don't know why," says Bob Williams, field supervisor of the U.S. Fish and Wildlife Office. Scientists still aren't sure why the Devils Hole Pupfish is on the brink of extinction. One thing they do all agree on is that water across the Mojave Desert is less abundant today than it was 11,000 years ago. Today's conditions are linked to a series of old or ancient (paleo-) tectonicand meteorological events...
Rising mountains to the west captured clouds, snow and glacial ice.
The formation and subsequent drying of more than a half dozen valley-wide lakes due to the ever increasing effects of a growing "rain-shadow".
Click on the top right image.
A changing climate left only wisps of humidity above and cubic miles of a sand-filled, rock-lined basins holding prehistoric "fossil" water below,...resulting in the final desertification of water across the Pacific Southwest.
Mojave Desert Pupfish Species and their Habitat Locations
The below agencies oversee the management of the Devils Hole and its Pupfish.
The water that has remained is squeezed to the surface in precious few places
across the arid land ecosystems of the Pacific Southwest. When and
where water does come to the surface, creatures dependant on aquatic
ecosystems have found refuge. One of these openings is called Devils Hole and one of these creatures is the Devils Hole Pupfish. To view the remaining "pupfish friendly" habitats locations across the Mojave Desert, click on to enlarge photo above.
The entire exposed surface of the Devils Hole Pupfish's aquatic habitat
consists of a space less than 60 feet long and 10 feet wide (18 x 3
meters). Inches below the surface, on a shallow rock platform, about the
size of two pick-up beds, end to end, their continued existence is
dependent upon the successful spawning of just one generation living
only 6 to 12 months. The entire population may consist of as few as
+/-38 adult individuals and an equal number of larval offspring
Where did the Devils Hole Pupfish come from?
"When and how pupfish joined that community is something of a mystery, because there is no evidence that, since opening, Devils Hole has had a surface water connection to the perennial Ash Meadows springs." (A. C. Riggs and J. E. Deacon, 2002; page 33)
Some possible and often suggested hypotheses include:
Swam an underground maze from one sunlit habitat to another (Not likely)
Swam into the mouth of Devils Hole from outside eventually forming an isolated population (speculation only with little to no evidence to support either water flowing in or water flowing out; however, geologic evidence may have eroded away over the years.)
Possible wind-aided dispersal of eggs or individuals (hypothetical mechanism)
Eggs or individuals were or carried in by a non-human source (hypothetical mechanism)
Eggs or individuals were carried in by a human source (hypothetical, improvable, but possible)