ihDANGERED ECOSYSTEMS IN COLORADO 
Thanks to the Endangered Species Act, in recent 
years there has been much concern for the na- 
tions's vanishing plants and animals. But there 
is no comparable Endangered Ecosystem Act, in 
spite of the extensive loss or alteration of 
many of the nation's major natural ecosystems: 
the tallgrass prairies of the eastern plains, 
northern hardwood forests of the northeastern 
U, S., tule-cattail wetlands in the uppermidwest, 
old-growth forests of the northwest coast, etc. 
There is no fereral, state, or local mandate 
that confers concern for the little bluestem 
prairies that once covered considerable parts of 
the loess region in eastern Kit Carson, Cheyenne, 
and Kiowa counties in Colorado, or for the unique 
Bigelow sagebruch-Frankenia community that is re- 
stricted to limestone bluffs in the upper 
Arkansas River Valley, or the newly discovered 
curl leaf mountain mahogany forest (trees up to 
20" in diameter and probably 300-500 years old) 
of Moffat County, or for the ephemeral freshwater 
ponds of the plains that bloom with fairy shrimp 
after heavy suraner rains, or for the "hanging 
gardens" of Mesa County. 
Colorado, because of its rugged topography, 
varied geology, and central geographic position 
is blessed with a rich ecosystem diversity^ in 
addition to its rich floristic diversity. Vet 
much of this diversity has been lost or altered 
• n the period since settlement. Grandparents 
$ho were born on homesteads in Colorado in the 
early 1900's may remember their parents talking 
of how much more grass there was in the early 
days. Much of the damage to the grassland 
vegetation of the state occured during the 
period of unregulated grazing from about 1870 to 
1920. Though many people feel the grass- 
lands of Colorado are heavily overgrazed, most 
old-timers seem to agree that the ranges of 
the state are in much better condition now than 
they were in at the turn of the century, largely 
because of the work of the federal land 
management agencies. 
It is possible to find "relict" natural grass- 
lands in areas that are far from water or are 
isolated. Tiny examples of western Colorado's 
once plentiful Indian ricegrass-needleandthread 
grasslands were located by Jim Ratzloff, a 
botanist formerly with the BLM’s Montrose 
District, They are isolated on mesa tops in the 
Dolores River Canyon, only accessible by 
helicopter. 
Most ecologists today accept that fire is a 
natural part of the life of many ecosystems, 
particularly in the Rocky Mountains, But, 
evidence is accumulating, from tree-ring dating 
and fire history studies, that the state was 
marked by unprecedented large-scale fires that 
destroyed most of the older forest, 
The annual flood cycle that may have created and 
maintained conditions suitable for devel- 
opment of the vertebrate- rich riparian cotton- 
wood forests of the South Platte and Arkansas 
Rivers is now under control by dams and irri- 
gation, These cottonwoods appear to be dying 
out in many areas and invading in others, at- 
tempting to adjust to the new domestic water 
regime. 
Aquatic ecosystems in Colorado have suffered 
extensively. In this dry region, there is very 
little water that is not used for some agri- 
cultural or human-related use. In preparing A 
preserve design for a segment of the Arikaree 
River in Yuma County, The Nature Conservancy, 
after consulting with a ground water hydrolo- 
gist, discovered that, if current trends in use 
of water for center-pivot irrigation continue, 
the Arikaree River will have no surface water in 
30-40 years, and the stream segment targeted for 
protection could be dry in 10-15 years. Current 
trends in water use in the region un- 
derlain by the Ogallala aquifer (a large part of 
eastern Colorado) are such that all streams in 
this region are drying from their headwaters 
toward the Kansas-Nebraska borders at the rate 
of up to a mile a year. In 40-50 years, there 
may be no surface water in any of this part of 
eastern Colorado, and this part of the aquatic 
diversity will be effectively extinct. 
Similar scenarios are developing in western 
Colorado where energy-related water use is 
skyrocketing. Conservationists concerned with 
protection of the state's aquatic systems may 
have to change their scale of concern from 
protection of a few acres of riparian forest to 
protection of entire aquifers and complete 
watersheds. 
WHY PROTECT ECOSYSTEMS? 
"To keep every cog and wheel is the first pre- 
caution of intelligent tinkering," said A! do 
Leopold, An ecosystem is all the plants and 
animals (cogs and wheels) in a part of the 
landscape, plus their environment. In the same 
way that a machine is an organized structure of 
cogs and wheels, an ecosystem has structure: a 
characteristic group of plants and animals, 
certain food production and transfer paths, and 
character-nutrient cycles. The most persistent 
engineer, if confronted with a huge pile of 
wheels and cogs from all the dismantled ma- 
chinery of the world, could never reconstruct 
the machines, particularly if he was without 
models, plans, or examples. The second rule of 
intelligent tinkering should be to keep a fully 
assembled example available for study. We need 
to not only protect the plants and animals, but 
also the ways in which they are organized into 
ecosystems. Land managers, with the good in- 
tention of repairing past damage, cannot know 
what needs to be done without knowing how the 
system used to look and function. 
