| Rio San Bernardino | |
|---|---|
  Location of mouth | |
| Location | |
| Country | United States,Mexico |
| States | Arizona,Sonora |
| Physical characteristics | |
| Mouth | |
• coordinates | 30°48′N109°11′W / 30.800°N 109.183°W /30.800; -109.183 |
| Basin features | |
| River system | Bavispe River |
TheRio San Bernardino, orSan Bernardino River, begins in extreme southeasternCochise County, Arizona, and is a tributary of theBavispe River, inSonora,Mexico.[1]
The Rio San Bernardino has two major tributaries, theRio de Agua Prieta and theArroyo Cajón Bonito. The river's headwaters are in extreme southeastern Cochise County, Arizona asBlack Draw. From here the Rio San Bernardino flows south, crossing into Mexico east ofDouglas, Arizona. In northernSonora, the Cajón Bonito River joins the San Bernardino River in theSan Bernardino Valley after draining theSierra San Luis and northern end of theSierra Madre Occidental.[2] Next the Rio San Bernardino is joined by the Agua Prieta River which also begins in Cochise County, crossing south asWhitewater Draw into Mexico atDouglas andAgua Prieta. The Agua Prieta River flows south and east to join the Rio San Bernardino, shortly after the Rio Agua Prieta has its confluence with theRio Fronteras, the latter flowing north from nearNacozari de Garcia, Sonora. The San Bernardino River joins theBavispe River atMorelos, Sonora at the northern end of theSierra del Tigre. The Bavispe River flows south by southwest to theYaqui River and eventually to theGulf of California atCiudad Obregon, Sonora.[1]
North American beaver (Castor canadensis) were documented by Leopold in 1977 in northern Mexico, and a 2000 survey found five breeding pairs of beavers on the Cajón Bonito River mostly in remote ranches without livestock. The authors of the latter study reported that local ranchers kill beavers because they fear felled trees will block roads. However, beavers are considered keystone species and ecosystem engineers, as their dams raise the water table and turn seasonal stretches of streams into perennial reaches, producing highly beneficial impacts onspecies abundance and diversity in the riparian zone.[3] Beavers were also documented by Hendrickson et al. in 1978 on the Cajón Bonito.[4]
| International | |
|---|---|
| National | |
