Pronatura Noroeste is preparing a new study of Yuma’s Ridgeway Rail (Rallus obsoletus yumanensis) in the Colorado River Delta, for which telemetry will be used as a data gathering technique. Some species specimens will be tagged with transmitters to follow their path and thus identify their movements.
The Yuma Ridgeway’s Rail is an endemic bird in the lower basin and the Colorado River delta, and is protected in Mexico and the United States. Its population decreased due to loss of wetlands in the basin, which is why it is considered to be in danger of extinction. The work of Pronatura Noroeste, has been documented that 75% of the global population of this bird is found in the wetlands of the Colorado River delta in Mexico, particularly at Cienega de Santa Clara, Sonora.
As part of the ecological monitoring program, in coordination with the Upper Gulf of California and Colorado River delta Biosphere Reserve, Pronatura Noroeste evaluates periodically the delta wetlands to understand habitat variations and the stability of Ridgeway’s rail and other species populations.
The association record -since 2009- shows an increasing number of individuals in certain wetlands has increased, since the habitat has improved with restoration activities in the area.
By using telemetry, the researchers will see the movements of the birds to know if they travel between wetlands, how they use them, and how the binational landscape is connected. This analysis of the specie’s movements will allow regional estimates to propose strategies for water and habitat management on the Mexico-USA border.
The monitoring of the birds will begin in the summer for certain areas in the delta: Cienega de Santa Clara, El Doctor, Hardy River, Colorado River, Mesa de Andrade, and Las Arenitas in Mexico. For the development of this project, Pronatura Noroeste collaborated with Dr. Courtney J. Conway and Eamon Harrity, Department of Fisheries and Wildlife Sciences of the University of Idaho, who have been conducting telemetry studies of the Ridgeway’s Rail in Nevada and California, United States.
To learn more about the Yuma Ridgeway’s Rail check:
Harrity, E. J., and C. J. Conway. 2018. Dispersal and migration behavior of Yuma Ridgway’s rails. 2018 Annual Report. Wildlife Research Report #2018-1. Idaho Cooperative Fish and Wildlife Research Unit, Moscow, ID.
Hinojosa-Huerta, O., R. Guzmán-Olachea, J. Butrón-Méndez, J.J. Butrón-Rodríguez, and A. Calvo-Fonseca. 2013. Status of marsh birds in the wetlands of the Colorado River delta, Mexico. Ecological Engineering 59: 7-17.
Hinojosa-Huerta, O., J.J. Rivera-Díaz, H. Iturribarría-Rojas, and A. Calvo-Fonseca. 2008. Population trends of Yuma Clapper Rails in the Colorado River delta, Mexico. Studies in Avian Biology 37: 69-73.
