510
BERNARD L. FONTANA
and Lower Gila, that at least four species of oak trees are common as
well as cottonwood (Populus fremontii), Goodding willow (Salix gooddingii), velvet ash (Fraxinus velutina var. toumeyi), walnut (Juglans
major), Arizona sycamore (Platanus wrightii), and Mexican elder (Sambucus mexicana). Other trees, shrubs, and perennials characteristic of
these river valleys are listed by Shreve (Shreve and Wiggins, 1964, pp.
77-80). Nor are these valleys without their cacti, including both prickly
pears and chollas {Opuntia spp.) as well as the saguaro (chiefly in Arizona) and organ pipe (chiefly in Sonor a).
d. Water. With respect to availability of surface water, all these rivers
have more water in them during and after the summer and winter precipitation seasons. At certain seasons all also have dry stretches in them, more
so today, in fact, than 250 years ago. Changes in climate, changes brought
about by Homo sapiens, and changes effected by the introduction of cattle
have in the past 70 or 80 years brought about channel cutting and erosion
and a depletion, by diversion or otherwise, in the amount of water running
throughout the entire courses of these streams. In 1700, they were more
shallow—even surface-flowing in many places—and less intermittent and
interrupted than they are today [see Hastings and Turner (1965) for an
analysis of the entire problem].
Because the rivers themselves supply—or, at least, formerly supplied—
surface water, ephemeral tributaries, rock tanks, springs, and charcos were
of correspondingly less importance to the maintenance of life.
e. Animal Life. The river valleys and surrounding mountains also were
the habitats for heavy concentrations of wildlife (see Cockrum, 1960).
The word "were" has to be used because these same valleys are today
those which support the densest populations of Homo sapiens, a mammal
not presently noted for living in a harmonious ecological balance with
other fauna. The wildlife in these valleys and mountains about 1700 was
essentially the same as that found in the central area, except that black
bear (Euarctos americanus), coati (Nasua narica), porcupine (Erethizon
dorsatum), raccoon (Procyon lotor), and possibly the American bison
(Bison bison) should be added to the list. The mountain lion and whitetailed deer are also more common to these regions, with the exception
of the Lower and Middle Gila again. This is also the case with the gray
wolf. The muskrat (Ondatra zibethicus) and beaver (Castor canadensis)
are native to both the San Pedro and Middle Gila rivers.
As even a cursory glance at the distribution maps in Phillips et al.
(1964) will indicate, bird life along the stream ways is infinitely richer and
more diverse here than elsewhere in Pimeria Alta. The presence of water
and protective vegetation in these valleys and their tributaries, not to mention increased sources of food from vegetation and insects, make the
BERNARD L. FONTANA
and Lower Gila, that at least four species of oak trees are common as
well as cottonwood (Populus fremontii), Goodding willow (Salix gooddingii), velvet ash (Fraxinus velutina var. toumeyi), walnut (Juglans
major), Arizona sycamore (Platanus wrightii), and Mexican elder (Sambucus mexicana). Other trees, shrubs, and perennials characteristic of
these river valleys are listed by Shreve (Shreve and Wiggins, 1964, pp.
77-80). Nor are these valleys without their cacti, including both prickly
pears and chollas {Opuntia spp.) as well as the saguaro (chiefly in Arizona) and organ pipe (chiefly in Sonor a).
d. Water. With respect to availability of surface water, all these rivers
have more water in them during and after the summer and winter precipitation seasons. At certain seasons all also have dry stretches in them, more
so today, in fact, than 250 years ago. Changes in climate, changes brought
about by Homo sapiens, and changes effected by the introduction of cattle
have in the past 70 or 80 years brought about channel cutting and erosion
and a depletion, by diversion or otherwise, in the amount of water running
throughout the entire courses of these streams. In 1700, they were more
shallow—even surface-flowing in many places—and less intermittent and
interrupted than they are today [see Hastings and Turner (1965) for an
analysis of the entire problem].
Because the rivers themselves supply—or, at least, formerly supplied—
surface water, ephemeral tributaries, rock tanks, springs, and charcos were
of correspondingly less importance to the maintenance of life.
e. Animal Life. The river valleys and surrounding mountains also were
the habitats for heavy concentrations of wildlife (see Cockrum, 1960).
The word "were" has to be used because these same valleys are today
those which support the densest populations of Homo sapiens, a mammal
not presently noted for living in a harmonious ecological balance with
other fauna. The wildlife in these valleys and mountains about 1700 was
essentially the same as that found in the central area, except that black
bear (Euarctos americanus), coati (Nasua narica), porcupine (Erethizon
dorsatum), raccoon (Procyon lotor), and possibly the American bison
(Bison bison) should be added to the list. The mountain lion and whitetailed deer are also more common to these regions, with the exception
of the Lower and Middle Gila again. This is also the case with the gray
wolf. The muskrat (Ondatra zibethicus) and beaver (Castor canadensis)
are native to both the San Pedro and Middle Gila rivers.
As even a cursory glance at the distribution maps in Phillips et al.
(1964) will indicate, bird life along the stream ways is infinitely richer and
more diverse here than elsewhere in Pimeria Alta. The presence of water
and protective vegetation in these valleys and their tributaries, not to mention increased sources of food from vegetation and insects, make the