DESERT EXPOSURE
APRIL 2016 • 29
The Chiricahua leopard frog is named for its leopard-like spotting and its native range in Arizona’s Chiricahua Mountains. (Photos Courtesy of U.S. Fish and Wildlife Service)
Moreno Bog before and after conservation workers joined to create a pool for the native fish and frogs.
WILD WORLD • CRAIG SPRINGER
Water is Life in the Desert
Moreno Springs rehab site is an oasis for rare fish and frogs in the Mimbres River
D
iligent hands make for great wealth, and a great many hands took part in a conservation project on the Mimbres River near San Lorenzo, New Mexico. The cooperative project between the U.S. Fish and Wildlife Service and private landowner, The Nature Conservancy, is paying dividends for wildlife habitats in the short- and long-term. With some planning and meeting of the minds, the outcome has been a boon to animals native to the Mimbres watershed. The Mimbres River flows out of the Gila Wilderness and off the west flank of the Black Range of southwestern New Mexico, part of a physiographic province called the Mogollon Rim that spans in a massive arc over parts of New Mexico and Arizona. The Mogollon is biologically rich in habitats for a diverse array of mammals, fish and amphibians, and resident and migrating birds. That biological diversity is in full display on the Mimbres River and it’s in need of help from a conservation standpoint. After pouring off the cragged mountainsides, the river threads through canyons that most anywhere along the way look like they could be scenes on tourism advertisements. As the stream makes its way downhill it purls past spare flat fields of alfalfa, orchards, chile farms and cow pastures. What’s left of the river is soaked up by sun and sand. And the fact the river naturally terminates on the desert floor points to the region’s biological diversity. It is home to the Chihuahua chub — the only place in the United States where this threatened fish species occurs. In a curious artifact of natural his-
tory, the fish has also persisted far to the south in the Guzman Basin of Mexico. By the character of its existence, the fish is uncommon. But it became all the more rare with habitat loss when the stream’s course was channelized for flood control. Competition with non-native fishes that struggle with the native chub for food and space in the river were a factor too. The Chihuahua chub was thought extinct for many years until it was rediscovered in 1975. The basin is also home to the threatened Chiricahua leopard frog, so named for its leopard-like spotting and its native range in Ari-
zona’s Chiricahua Mountains. What has harmed the chub has diminished the number of frogs as well — the lack of habitat. “Mimbres” is Spanish for “willow.” The Mimbres River used to be lined with willow thickets, especially at its terminus. Soppy soils and wetlands needed by frogs are fewer now. Couple that with non-native bullfrogs across its range and it’s hard going for the native amphibian. To further insult, the Chiricahua leopard frog faces an insidious Chytrid fungus that makes it susceptible to illness and predation. So, a patch of flat field along the Mimbres River holds the promise of
improving the lot of two animals in greatest need. The 208-acre Upper Mimbres Preserve owned by The Nature Conservancy encompasses much of Moreno Spring, named for the neighboring landowner. The spring emanates over a large area and not from a single point in the ground. Think of it as a large spongy area with hummocks of dry ground between pockets of mushy soil with some open waters interspersed. One can imagine easily that the Mimbres River meandered by at a time, elbowing into the foot of a low bluff where the spring now exists. The spring may be a relic of a former river
channel. No matter the case, it is today a reliable water source in an arid land and one that could be improved upon. And that’s exactly what happened in 2014. The Nature Conservancy and the Service’s Partners for Fish and Wildlife Program teamed up to improve Moreno Spring for the benefit of Chihuahua chub and Chiricahua leopard frog. Partners for Fish and Wildlife is a cost-share program whereby private landowners can conduct wildlife conservation work in
WILD WORD
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Genetic reserve
The Chihuahua chub occurs only in the Mimbres River.
Since 1979, the Southwestern Native Aquatic Resources and Recovery Center in Dexter, New Mexico, has been the backup for Chihuahua chub. A captive stock of chub lives there. It is a refuge of sorts, with so few of the chub persisting in the wild. Using conservation genetics, scientists at the U.S. Fish and Wildlife Service facility intensively manage the brood fish and offspring to ensure that fit and healthy Chihuahua chubs are put back into the Mimbres River.