University of Virginia Library

Biota:

According to archaeologic evidence, the present flora and fauna of
the Chaco area have altered somewhat, but not radically, during the
past millenium. Rushes, canes, willow twigs, timbers of yellow pine,
cottonwood, willow, and spruce, and charcoal from piñon and Douglas
fir, found in excavations, indicate a closer supply of these items than
is true at present. It is much more logical to bring the forests of pine
and piñon thirty miles closer from the Continental Divide and the
Dutton plateau than to believe that the prehistoric inhabitants of the
Chaco lugged by hand great logs (one remnant of a post or pillar has
been found that measured 26½ inches in diameter) over long distances.
Furthermore, there are still a few scattered piñon trees on the mesas
north and south of the Chaco; and a few lonely yellow pines were
growing on the mesa south of Casa Rinconada and in the side arroyos
of the Chaco Canyon until a dozen years ago.[10] The last yellow pine
near Pueblo Bonito (on the south mesa) was cut down for fire wood
in 1927, so that now the nearest pines are some sixteen miles up the
canyon. Jackson, in 1877, reported cottonwoods down stream from
Pueblo Bonito. All these have died, and now the nearest cottonwood
trees are eight miles up the canyon. It is not unreasonable to assume
that during a portion, at least, of the prehistoric period, the Chaco
River flowed between low banks—possibly through a series of pools—
which were bordered by growth of rushes, canes, willows, and cottonwoods.
Not only is there archaeologic and documentary evidence for
a former existence of such growths near the main sites, but there is
also corroboration of the postulated surface supply of water in the considerable
number of frogs carved in turquoise and modeled in terra
cotta.

The present vegetation of the canyon floor is chiefly of the Great
Basin microphyll desert type,[11] characterized especially by sagebrush
(Artemisia). On the alluvial flats of the canyon floor, at an average
elevation of six thousand feet, greasewood (Sarcobatus vermiculatus)
is dominant, associated with sagebrush, bunch grasses (Sporobolus),
rubberweed (Hymenoxys), tumble weed (Salsola pestifer), salt bushes
(Atriplex), rabbit brush (Chrysothamnus), blue grama (Bouteloua
gracilis), galleta grass (Hilaria jamesii), feather grass (Stipa), poverty
grass (Aristida), crownbeard (Verbesina), etc. On talus slopes,
rocky ledges, and scattered over the mesa and valley surfaces of the
Chaco plateau are occasional yuccas and cacti. The shallow, stony
soils of sandstone ridges and mesas carry a sparse vegetation of junipers
(Juniperus, locally called cedars), piñon (Pinus edulis), and sagebrush,

with parklike openings scantily covered with steppe grasses. The
inter-mesa tracts are vegetated with sagebrush, rubberweed, blue
grama grass, some prickly pear and cane cacti (Opuntia), and other
grasses and cacti. Very sandy soils support joint fir (Ephedra) and
redtop grass (Agrostis). Along the ponds and lakes of the area grow
carrizo (Phragmites phragmites), rushes (Juncus), bulrushes (Scirpus)
and sedges (Carex). During the past three years the Soil Conservation
Service has planted in the Chaco Canyon more than 330,000 trees
and shrubs, and a couple of thousand pounds of grass seed.[12]

The fauna of the Chaco area has been almost totally neglected by
zoologists. From archaeologic and historical studies, however, it is
evident that very few if any newcomers have appeared upon the scene
since the abandonment of the Chaco Canyon pueblos. On the other
hand, American antelope or pronghorn (Antilocapra americana americana),
American elk or wapiti (Cervus canadensis), mule deer (Odocoileus
hemionus macrotis), bighorn sheep (Ovis canadensis canadensis
and O. c. texiana), and bears (Euarctos and Ursus) seemingly once
inhabited the Chaco plateau. At present not one of these mammals is
to be found in the area. Antelope have been gone from the valleys for
more than 50 years; mule deer and elk have not been seen in this part
of New Mexico for at least a generation; while the bears have retreated
to the adjacent mountains, and the bighorn sheep have hidden
out in the San Juan Mountains or retired to southern ranges. These
animals, mainly herbivorous, were apparently driven out by man
through hunting and the introduction of domesticated grazing animals.
With the large herbivores went the carnivores, mainly Felidae, that
had preyed on them. This opened the field to rapidly multiplying
throngs of smaller fry, among whom the rodents took the lead. At
present the mammalian life of the Chaco area is dominated by rabbits,
hares, rats, mice, prairie dogs, gophers, and squirrels—with an occasional
coyote or fox to place a slight curb upon the rodent multiplication.
In actual fact, however, probably hawks, owls, and snakes prey
to a greater extent upon the rodents than do the Canidae.

A list of the more common rodents would include: the Texas
jackrabbit (Lepus californicus texianus), Colorado cottontail (Sylvilagus
auduboni warreni), Rocky Mountain cottontail (Sylvilagus nuttalli
pinetus), chipmunks (Eutamias), at least four species of
squirrels (Sciurus, Citellus, and Ammospermophilus), the Zuñi prairie
dog (Cynomys gunnisoni zuniensis), about a dozen kinds of mice, six
species of rats, an occasional porcupine (Erethizon), the golden pocket

gopher (Thomomys perpallidus aureus), and beaver (Castor canadensis
frondator) in the San Juan river. Within the Chaco Canyon proper
the Moki kangaroo rat (Dipodomys longipes), banner tailed kangaroo
rat (D. spectabilis baileyi), Baird's pocket mouse (Perognathus flavus
flavus), scorpion or grasshopper mouse (Onychomys leucogaster melanophrys),
white-footed or tawny deer mouse (Peromyscus maniculatus
rufinus), antelope ground squirrel (Ammospermophilus leucurus cinnamomeus),
Zuñi prairie dog, golden pocket gopher, Texas jackrabbit,
and Colorado cottontail rabbit are the rodents most frequently seen.
It is probable that a thousand years ago, when coniferous forests extended
into the Chaco area, there were numerous representatives of
tree squirrels (Sciurus), wood rats (Neotoma), and other forest loving
rodents that are now rare or absent. Three species of wood rats (Neotoma
lepida lepida, N. mexicana fallax, and N. cinerea arizonae) do inhabit
the rocky cliffs and ledges of the Chaco, where they erect nests
of saltbush branches, pieces of cactus, etc.

Among the carnivores occasionally seen in the Chaco area (and
presumably more common in past time) are: mountain lions (Felis
concolor), plateau wild cat (Lynx rufus baileyi), western red fox
(Vulpes macrourus), New Mexico desert fox (Vulpes macrotis neomexicana),
Arizona gray fox (Urocyon cinereoargenteus scottii), gray wolf
(Canis lycaon nubilus), San Juan coyote (Canis latrans estor), mink
(Lutreola vison energumenos), Arizona weasel (Mustela arizonensis),
Arizona skunk (Mephitis mesomelas estor), badgers (Taxidea taxus),
and the bears mentioned previously. Of the Chiroptera there are a
number of species in the Chaco area including, certainly, the brown bat
(Eptesicus fuscus fuscus), and the black-nosed bat (Myotis subulatus
melanorhinus).

The bird, reptilian, molluscan, arthropod, and lower forms of life
have been practically unstudied in the Chaco Canyon area. Among the
birds definitely identified in the Chaco Canyon are: the redwinged
blackbird (Agelaius phoeniceus), cowbird (Molothrus ater), western
crow (Corvus brachyrhynchos), western mourning dove (Zenaidura
macroura marginella), golden eagle (Aquila chrysaetos), red-shafted
flicker (Coleptes cafer collaris), hawks (Buteo sp.), piñon jay
(Cyanocephalus=Gymnorhinus cyanocephalus), Woodhouse jay
(Aphelocoma californica woodhousei), Shufeldt's junco (Junco oreganus
shufeldti), Arkansas kingbird (Tyrranus verticalis), horned
larks (Otocoris alpestris), American magpie (Pica pica hudsonia),
nighthawks (Chordeiles sp.), Bullock's oriole (Icterus bullocki), owls
(several species), scaled quail (Callipepla squamata pallida), American
raven (Corvus corax), white rumped shrike (Lanius ludovicianus excubitorides),
sparrows (Chondestes, Spizella, etc.), cliff swallow
(Petrochelidon albifrons), thrushes (Hylocichla sp.), canyon towhee

(Pipila fuscus mesoleucus), thrashers (Toxostoma sp.), vulture (Cathartes
aura septentrionalis), woodpeckers (Dryobates, etc.), and wrens.
Occasionally water birds, such as mallards, pintails, teals, and grebes,
may be seen in passage across the Chaco. The wild turkey (Meleagris
gallopavo), which is now found no closer than in the Zuñi, Chuska,
Jemez and San Mateo mountains, once probably roamed the forested
areas of the Chaco and Dutton plateaus.

Amphibians necessarily, in this arid area, are not numerous. At
present only the toad (Bufo sp.), and the leopard frog (Rana pipians)
are known by the writer to exist in the Chaco area. Undoubtedly frogs,
toads, and salamanders were present in considerable numbers when
the Chaco possessed a greater water supply. Lizards are numerous,
including Bailey's collared lizard (Crotaphytus collaris baileyi), western
earless lizard (Holbrookia maculata approximans), southern brownshouldered
uta (Uta stansburiana elegans), striped swift (Sceloporus
consobrinus), and horned toads (Phrynosoma sp.). Among snakes
noted are: the western striped racer (Coluber taeniatus taeniatus),
western bull or gopher snake (Pituophis catenifer), white-bellied garter
snake (Thamnophis eques), prairie rattlesnake (Crotalus confluentus=
C. viridis), wandering garter snake (Thamnophis ordinoides elegans),
and the whip snake (Masticophis flagellum flavigularis). Although not
noted by the writer, it is possible that a few mud turtles and tortoises
exist in the Chaco area. Pepper, during his excavations at Pueblo
Bonito, found both carapace and dried "turtle" carcass. A few small
land snails, species unknown, may be found in the canyon. As there is
no permanent stream there are no fish. Various unidentified flies, mosquitoes,
grasshoppers, beetles, bugs, butterflies, moths, hornets, wasps,
bees, ants, spiders, centipedes, scorpions, millipeds, Crustacea, worms,
etc., are present.[13]