Biology
professor searches state for rare Southwestern river otter
By Steve
Carr
UNM Research
Associate Professor of Biology Paul Polechla is in search of
an animal subspecies that hasnt been collected in New
Mexico for half a century or in the desert Southwest in nearly
30 years.
 |
| UNM
Research Associate Professor of Bilogy Paul Polechia displays
a stuffed speciment of th elusive Southwestern river otter. |
His research
on the elusive Southwestern river otter is featured in the June/July
issue of National Wildlife Federation magazine.
The
Southwestern river otter is one of the most endangered mammals
in North America, Polechla said. Even more so that
the Mexican gray wolf. There is no captive population and no
one has identified an existing population in the wild. For example,
we have both wild and stocked populations of the Mexican wolf
and the black-footed ferret.
Polechla
has studied the otter and its habitat from Alaska to Florida,
Maine to California and Canada. He has even studied the Neotropical
(or Southern otter) of Mexico. Now, one of his primary search
areas for the Southwestern river otter is located along the
rivers in the Gila Wilderness near Silver City, N.M., which
is the area where the Southwestern species was last captured
in New Mexico. Unfortunately he has yet to uncover any hard
recent evidence of the elusive carnivore.
Once a
thriving species across the state, the last time a Southwestern
river otter was caught in New Mexico was in 1953, which a state
wildlife officer caught. The stuffed specimen sits in a display
case at UNMs Museum of Southwestern Biology, while its
skeleton is kept on display in the Smithsonian.
Although
I continue to receive reports of them in New Mexico, Im
searching for something that has been officially regarded as
locally extinct, Polechla said. Yet, few thorough
surveys have been done by competent observers in New Mexico
and the Southwest. I started studying the otter 20 years ago
in Arkansas where their populations are healthy. They are secretive
and exceedingly difficult to see in nature. You have to be skilled
and a very lucky biologist. Usually, all you get to see are
their tracks, droppings and the signs they leave behind.
Unaided
by live traps or radiotelemetry, Ive seen otters on 12
occasions and I have each sighting stamped in my head of who
I was with, where I was and the lay of the land. The last time
I saw one was on the North Payette River in Idaho last fall.
I saw a mother and her two pups. I watched for over an hour.
Its a great feeling when you see one. It even gives me
a thrill when I see their tracks and scats.
There are
seven different North American river otter subspecies, some
of which have been reintroduced into the wild in the Southwest.
Polechla studied one of their populations in Southwestern Colorado
last year. Otters vary in size, but generally grow to four feet
long weighing approximately 20 pounds. River otters spend part
of their time on land and part on the river. Otters use the
river to hunt and travel. Unlike land animals, otters follow
drainages, which is why Polechla searches waterways for clues
of otter presence.
He says
that the otters prey, as well as the otters themselves,
are dependent on good water quality and ample fish and or crayfish
prey. His search areas include what he calls the corridor
of dispersal and the otters possible route of movement,
which involves several of the main waterways in New Mexico including
the northern Rio Grande, San Juan River, Pecos River, Canadian
River and the Gila. He has completed five major studies in New
Mexico and other states and has two proposals for additional
funding and research.
Otters
like adequate amounts of water, Polechla said. Otters
are indicators of good water quality for humans. They are also
a great model for the health of the aquatic environment. Everything
is hooked or linked together. Our jobs as biologists is to discover
the details of those links.
Currently
he is studying the diet of a presumably stocked population.
So far he has found suckers, sculpin, trout, stone flies and
crayfish in their scat. Polechla has performed otter research
for many entities including the U.S. Forest Service, U.S. Fish
and Wildlife, Defenders of Wildlife, and while he might be searching
for something that has been ignored in the desert Southwest,
it doesnt dampen his enthusiasm.
Copies
of the June/July issue of National Wildlife World edition magazine
featuring Polechla can be ordered through Mark Wexler, editorial
director, National Wildlife Federation, 11100 Wildlife Center
Drive, Reston, Va. 20190-5362 or on the Internet at www.nwf.org
or at UNM Centennial Library.