• Increase font size
  • Decrease font size
  • Print
  • RSS
  • Conservation on the creek: Biologists monitor Cienega’s wildlife

    In the Cienega Creek Natural Preserve it’s easy to forget you’re in the Sonoran Desert. 

    The preserve lies about 25 miles southeast of downtown Tucson, still very much in the desert, but here saguaro, ocotillo and cholla give way to dense grass stands and tall cottonwood, mesquite and willow trees. 

    One of the few remaining perennial streams and associated riparian ecosystems in southeastern Arizona, the Cienega Creek winds through the Preserve, supporting a wide variety of wildlife. An important aspect of County stewardship of the property is the ongoing wildlife monitoring program, which is the effort that has brought biologists from the Pima County Office of Sustainability and Conservation and Arizona Game and Fish Department together on a bright November morning. 

    “Tracking the status of fish populations at this site is just one of the various monitoring efforts that Pima County is involved with in its stewardship of this regionally valuable desert riparian system,” said Ian Murray, who works in Conservation Science with the Pima County Office of Sustainability and Conservation. “Regular fish monitoring at Cienega Creek is a critical means to provide surveillance for any invasions by nonnative species into this system.”

    Pima County’s ecological monitoring program is a function of the County’s Multi-species Conservation Plan, which addresses stewardship and conservation of 44 plant and animal species.

    With hip waders, nets and buckets in tow, the group sets out from the Gabe Zimmerman Trailhead parking lot down to the streambed in search of pools that may contain fish like longfin dace, Gila chub or Gila topminnow. 

    At the first stop, water flows in the creek are sparse, with just a trickle of water a few inches deep and a couple feet across in most areas. Significant pools also aren’t present, although a few small ones remain under stands of cottonwood trees and in the lees of rocky outcrops. 

    Cienega Creek Fish Survey
    In one of these pools, a small army of lowland leopard frogs has made a home. Although the frogs are not the reason biologists have come to the Cienega this day, they note the frog’s presence to inform future monitoring efforts. 

    Further upstream looks more promising, with larger water flows and bigger pools. But as is usually the case, the presence of water in the desert attracts many critters, including an aggressive hive of Africanized honey bees, which chases the biologists back to their trucks.   

    At a final stop the group finds success, visiting a stretch of creek under a canopy of trees where a large pool backs up against a hillside. They measure a 330-foot section section of stream and place markers every 20 feet. Two of the biologists then climb into the creek holding opposing sides of a seine net and begin to pull the net downstream, eventually corralling the fish against the shoreline, and scooping them into the net. The scientists then remove leaves and debris and transfer the fish into a bucket for counting. 

    On this day they counted 196 longfin dace, and 254 Gila topminnow. 

    “The continued presence of thriving native fish populations is one barometer indicating an ecologically intact system supported by healthy vegetation, soils, and water resources,” Murray said. 

    The Cienega Creek Natural Preserve stands as a successful example of the County’s conservation efforts. In 1986 when the Pima County Regional Flood Control District purchased the property, which had been part of a ranch, much of the landscape had been altered through years of heavy cattle grazing and off-road vehicle traffic. 

    Through creation of the Cienega Creek Natural Preserve, and the Flood Control District’s subsequent coordination of a management plan for the 4,000-acre preserve, the landscape has recovered. Evident throughout the Preserve are reestablished pools, the return of endangered aquatic species, and the regrowth of willow and cottonwood forests that form a canopy over the stream.  

    In addition to its role in monitoring water resources within the Preserve, the Flood Control District oversees protection and preservation of land within the Preserve in coordination with Pima County Natural Resources, Parks and Recreation. This work involves regular monitoring of property conditions, public use and utility maintenance. 

    The Preserve also has become an important site for scientific studies and monitoring programs in cooperation with other agencies.  

    A partnership the District formed with the University of Arizona works to study the age and flow path of groundwater in lower Cienega Creek and nearby Davidson Canyon. This project seeks to inform ongoing protection efforts of the water and riparian habitat resources.

    In 2015, the Flood Control District took over the monitoring of streamflow volumes, groundwater levels and water quality within the Preserve. To accomplish this, the District operates a network of automated rain and streamflow gauges utilized for water balance monitoring within the watershed and for flood warning to downstream areas, including metro Tucson.  

    In partnership with the U.S. Geological Survey, Bureau of Land Management and Arizona Department of Environmental Quality, a monitoring program has been established as a regional indicator for drought assessment and overall health within the Cienega Creek watershed.

    Cienega Creek Natural Preserve is free and open to the public. To visit, members of the public are required to request a hiking permit. More information is available on the Preserve's website.

    Follow UsShare this page

    Communications Office

    130 W. Congress
    Tucson, AZ 85701

    (520) 724-9999

    Monday - Friday 8 a.m. - noon and 1 - 5 p.m., except on holidays.


    Department Home Page
    Department News
    Department Feedback Form
    Subscribe to Pima County FYI Newsletter
    Volunteer with Pima County