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January 20086, Notes to accompany presentations and posters
<br />Progress Report on Inquiry Into Biological Issues in Water Transfers
<br />John Wiener (John.Wener@Colorado.Edu) (Not representing any institution).
<br />The Regional Picture is Missing. Too much has been changed already in the Eastern Plains of Colorado to presume we know
<br />much now, or can easily foresee consequences of more dramatic change from changes in water management, agricultural
<br />policy, or climate variation. Extreme losses of wetlands, drastic declines in plains fishes and birds, loss of native grasslands,
<br />and a great deal of research at scales of better value to science than management leave us in a difficult position. There are
<br />continental scale estimates, and micro-scale research, but regionally, little in the way of a "big picture" helpful for identifying
<br />thresholds, avoiding problems, or anticipating consequences. Agriculture accounts for well over 85 percent of consumptive
<br />use of water, but there is almost nothing on ditches and canals as part of the environment, or as partial substitute for converted
<br />and drained riparian and wet lands of all sorts. It is also known that created habitats have supported increases in bird species
<br />richness and numbers in some areas, including those which are partly urbanized.
<br />Management is Not in Government Control. There is little governmental interference in management of the various kinds
<br />of wetland and riparian areas affected by agricultural water distribution, until some drastic situation such an Endangered
<br />Species problem appears, with usually very inequitable distribution of costs on the state and people trying to act, rather than
<br />those who have already acted. These messes can cost a great deal.
<br />Minimum Intact Wetlands and Riparian Areas of all kinds are irreplaceable for restoration and least-cost maintenance of
<br />habitats, and the full set of kinds of wetted lands are wanted, with adequate connectivity so that native vegetation can compete
<br />successfully with invasives. The value of many kinds of wetlands may have been underestimated in the past.
<br />The agricultural landscape is not "natural" - in some ways it is much more biologically productive, and in some ways it is
<br />less desirable, but regardless of preference it is both "the only game in town" and not self-managing. This is a "hybrid
<br />ecology" with changes in all aspects, and it will not "go back" to some pre-development state if water is withdrawn. Soils
<br />irrigated for more than a century are profoundly changed, in physical and chemical qualities, and will not likely offer
<br />competitive advantage to native vegetation without long active amendment and management activity.
<br />Cottonwoods, Willows, and Russian Olive and Tamarisks interact in complex ways which are affected by flow regimes and
<br />timing of flows, the speed of changes in water levels, and the availability of conditions which foster each species more than
<br />others. The ecological succession along the mainstems has changed and invasives will be a problem requiring management
<br />attention and effort under any foreseeable future. Suspending irrigation and "drying out" a ditch may be an opportunity for
<br />state, federal, and local interests to cooperate in eradication, or it may be an opportunity for invasives to take advantage of
<br />drought-like conditions for existing vegetation. Active and attentive management is needed until we know which outcome will
<br />appear or can be made to result.
<br />Land Use Changes will interact with water transfers in important but usually unexamined ways. One important change is the
<br />rapid loss of middle-sized profitable farming, with consolidation of some land into huge operations and splintering of some
<br />land into non-commercial "life-style" ranchettes and such. These small parcels are a challenge for all kinds of management,
<br />from weeds to water uses and coordination or not with neighbors. In the 1997 Agricultural Census, 73% of farms made only
<br />5% of sales, but from 43% of farm land, which may include the most biologically valuable lands, with the highest habitat
<br />value. In one study found on this problem, 18 to 20% of the riparian vegetation in a foothills area was along ditches - it may
<br />be a much larger proportion out away from tributaries to the major streams. And even in the foothill area, only 1% of standing
<br />water was not human-made.
<br />Foresight and problem avoidance are not going to be cheap, but maybe less expensive than the opposite. After a century or
<br />more of irrigation, any "natural versus unnatural" distinction blurs, and the question is, "What happens with sudden changes to
<br />what exists now?" It may be desirable to invest inproblem-avoidance to prevent surprises and unfair distribution of costs
<br />imposed on those affected, while earlier actors are not involved in limitations, expenses, or remediation.
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