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Success Stories

Revegetating Mined-out Lands,Nevada

From Mine Waste to Grassland, Arizona

Restoring a Desert Oasis, Arizona

The Healthiest Riparian Area in North America?, NM
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The Healthiest Riparian Area in North America?
The riparian habitat that borders the Gila River as it flows across the U Bar
Ranch in southwestern New Mexico may be the healthiest in North America. Its
qualifications for that distinction certainly are impressive. According to
Scott Stoleson, Ph.D., Research Wildlife Biologist for the Rocky Mountain
Research Station in Albuquerque, the mature, diverse forests and lush
grasslands that grow along the Gila within the U Bar support the highest
density of songbird territories in North Americaan average of 1,300 per 100
acres. The next most dense known site supports 1,100. On the U Bar stretch of
the Gila 99% of the fish are native species and only 1% non-native. The
average for other streams in the Southwest is closer to the reverse of that.
Within
the U Bar's riparian habitat you will find the largest known
population of at least three threatened and/or endangered species. The
U Bar is home to between 30 and 40% of the entire known population of
endangered southwestern willow flycatchers. It also supports the
largest populations of two threatened fishes, the loach minnow and the
spikedace, which are listed by The Nature Conservancy as among the 500
most endangered species in the U. S. Another listed species doing well
on the U Bar is the Gila Chub. Other species, some rare and some not
so
rare, enjoying success on the U Bar include the common blackhawk,
Aberts towhee, Bell's vireo, Gila woodpecker, desert sucker and Sonoran
sucker.
David Ogilvie, who manages the U Bar, leases the ranch from the giant copper
mining corporation Phelps Dodge. Ogilvie points out that, in spite of the U
Bars success, it is still widely believed that cattle grazing is anathema to
most of the rare creatures that do so well within the ranchs environs. In
fact cattle grazing was blamed for making most of them rare. For that reason,
many who are concerned about the future of the southwestern willow
flycatcher, the loach minnow and the spikedace assume that the only way these
species can avoid extinction and begin to recover is if cattle grazing is
removed from all habitat that might serve to host their recovery.
In 1994, when the southwestern willow flycatcher was listed as endangered,
and the call went out to remove cattle from all land that qualified as
prospective habitat for the birds, Ogilvie wondered if some of the birds he
saw flitting through the trees alongside some old dirt irrigation ditches he
had recently rewatered were that kind of flycatcher. If they were, he knew he
could be forced to stop grazing some of the most productive land on the
ranch.
On Ogilvies advice Phelps Dodge hired a biologist to do a bird survey. (PD
has been supportive of this effort at every step, says Ogilvie.) The
biologist found that, not only did the U Bar support a population of
southwestern willow flycatchers, it was home to the largest population yet
discovered64 pairs. The next most populous site, the Kern River in
California, supported 38.
When the southwestern willow flycatcher was listed as endangered, it was
believed that the birds preferred dense thickets of willows in relatively
undisturbed areas as habitat. Eventually, it was determined that there are
two races of this species in theSouthwest; the Rocky Mountain race, which prefers dense thickets, and the
Southwestern race, which prefers mature stands of cottonwoods and boxelders
scattered across broad flood plains. This is exactly the kind of habitat that
Ogilvies management has created and sustained on the U Bar.
The existence of the U Bars superlative habitat dates back to a management
move Ogilvie made in 1994. At that time he started water flowing again
through a system of dirt irrigation ditches constructed by previous owners of
several small ranches that were consolidated to create the U Bar. As water
flowed through the ditches, they leaked, as all dirt ditches do, and groves
of dying trees along their banks began to revive. The trees had been enabled
to reach maturity because they were protected from wildfire by the cattle who
ate the grasses that might carry a fire to them, and they were protected from
being uprooted by floods by the earthen levees maintained by the ranches.
Now, once again nourished by water from the ditches, they grew, and the birds
came.
Nurtured in this ideal habitat, the U Bars southwestern willow flycatchers
are the most prolific naturally (i. e. not protected by predator control) of
any population known. As Ogilvie rewatered more ditches in 1995 and 96, the
count of rare flycatchers soared. After reaching a high of 200 pairs in 1999,
a severe drought was accompanied by a drop to 130 pairs in 2,000. The birds
that managed to persist on the U Bar, however, proved to be hard workers.
Nest success was the highest ever that year, declared Stoleson. 67% of
nests fledged at least one young. Thats the highest rate ever recorded on a
site where there is no predator control.
The endangered species that are doing so well on the U Bar have endorsed David Ogilvies management in the most significant way they canby taking up
residence and proliferating on the land he ranches. In spite of that, groups
that purport to be advocates for those species ignore the testimony of the
very creatures they claim to protect and continue to call for the removal of
ranching from prospective habitat. In the case of David Ogilvie and his
management, the results of such a move seem ominous. A survey of the U Bar
area in 1971 before Ogilvie began managing the ranch found no southwestern
willow flycatchers.
Other Success Stories
Revegetating Mined-out Lands,
Nevada
From Mine Waste to Grassland, Arizona
Restoring a Desert Oasis, Arizona
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