1. Restoring Colorado River Delta Wetlands
Yamilett Carrillo-Guerrero
University of Arizona, School of Renewable Natural Resources

2. Colorado River Delta, Mexico
California
Arizona
Sonora
Baja
California

4. Ecozones in the Colorado River Delta

5. The Colorado River Delta, Mexico
Critical migratory site and breeding area for sensitive species
Recognition: Biosphere Reserve, Ramsar Convention, WHSRN, and NAWCA

6. The Need for Restoration in the Colorado River Delta
* Major causes for wetland loss in the delta:
1. Lack of instream flows
2. Agricultural expansion

7. The Need for Restoration in the Colorado River Delta
* 76 % of delta wetlands were lost in last 100 years.
* Invasion of non-native species (Tamarisk spp.)

8. Protected Species in Mexico and US that occur the Colorado River Delta
Yuma Clapper Rail
California Black Rail
Least Bittern
Least Tern
Bald Eagle
Peregrine Falcon
Prairie Falcon
Brown Pelican
Wood Stork
Savannah Sparrow
Willow Flycatcher

9. Natural Restoration of Riparian Areas
Water Management
Policies and Regulations

10. Restoring the Colorado River Delta: A Binational Effort
Water Management
Estimates of 0.5% of annualized mean flow for Riparian Corridor.
Three-month spring flow of 3 x 108 m3 every 4 years , and
Perennial flow of 4 x 107 m3

11. Restoring the Colorado River Delta: A Binational Effort
Timing and consistency of excess flows.
Management Plan for Colorado River delta floodplain

12. Restoring the Colorado River Delta: A Binational Effort
Policies and Regulations
Recognition of ecosystem as user entitled to Colorado River water.
2) Environmental quota.

13. Restoring the Colorado River Delta: A Binational Effort
Policies and Regulations
Commitment to secure instream flows in the delta.
4) Involvement of local communities in the restoration process.

14. Restoration Initiatives from Local Communities

15. Proposals from Delta Communities
* Formal commitment of farmers not to take water out of river if an environmental quota was to be established by US and Mexico.
* The river and its banks should be declared a protected natural area.

16. Proposals from Delta Communities
* Restore riparian forests along the River.
* Conservation easements
* Each user should contribute to instream flow needs, proportionally to its use of water.

17. Pilot Projects of Restoration in the Delta
1. Environmental use of agricultural drainage water
2. Community wetland management and restoration
3. Farmland retirement for wetland restoration

18. GENERAL PURPOSE
To determine if a program to change land uses of farmland could be established in the Colorado River delta, Mexico, with the purpose of restoring wetland areas.

19. OBJECTIVES
a) Assess landowners disposition to change land use from agriculture to wetland restoration projects
b) Determine landowners’ disposition to lease their water rights for wetland conservation
c) Estimate the costs of a program of retiring the agricultural land.

20. MEXICO
USA
Riparian Potential
MEXICO
Marshland Potential

21. 2. SURVEY * Personal interviews
* Duration: 15 min. questionnaire, 1 hour interviews
* 32 Farmers contacted in Region 1 (38% area of study)
* 16 Farmers contacted in Region 2 (30% area of study)

22. QUESTIONNAIRE * Pre-tested with farmers outside study area * Topics:
a. Farmers’ perception regarding the Colorado River
b. Farmland characteristics
c. Farmland retirement program
d. Rent of water-rights

23. Region Land (Ha) $ Land ($US/yr) Water $ Water 1- Riparian 229
Land and Water Availability and Costs
Region
Land
(Ha)
$ Land
($US/yr)
Water
$ Water
1- Riparian
229
(566 acres)
$298,616
136.5
(1,106 af)
$36,991.5
2- Marsh
115
(284 acres)
$74,980 77
(624 af)
$20,867
Total
344 Ha
850 acres
$373,596
213.5 Ha
(1,730 af)
$57,858.5

24. International Wildlife Refuge in the Limitrophe Area
Proposed by Cocopah Indian Tribal Council
Encompass Limitrophe Area-International Boundary
(Arizona-Baja California)
Purpose: Preserve the Riparian Corridor in the International
Boundary
US Agencies supporting: USFWS, US Border Patrol
US Agencies against: IBWC, BOR?
Mexico’s position: Federal Government do not know,
Landowner’s in the area want the
riparian corridor a protected natural area

28. Why an International
Wildlife Refuge?

29. CONCLUSIONS
Ecosystem restoration is feasible in the Colorado River delta.
2. Restoration process could be embraced and maintained by local communities.
3. Farmers’ participation could yield more hectares restored than land purchases.
4. Rent of Water Rights in Mexico would not be enough to restore the delta.

30. As functions and values of wetlands in the Colorado River Delta provide benefits that do not consider political boundaries, management and restoration
of the delta ecosystem should be worked out as a bi-nationally shared responsibility.

31. This research was financed with grants from:
Sonoran Institute
Pronatura Sonora
Wallace Foundation
Environmental Defense