• Red Rocks with water in front of them in the desert.
  • Clouds behind Joshua Tree and bushes.
  • Desert flowers blooming in bushes in front of mountains in the desert.
  • Setting sun reflecting of clouds of orange and blue behind a joshua tree.
  • Hoover Dam intake towers with water behind the dam showing that it is not full.


Predicting Effects of Climate Change on Riparian Obligate Species in the Southwestern United States

Science Need(s)

Projecting changes in the distribution of riparian plant communities; Projecting changes in the distribution and populations of wildlife that are dependent on large rivers or permanent streams; Obtaining climate information relevant to the Desert LCC; Projecting natural system responses to changes in climate, hydrology, etc.; Projecting changes to endangered species habitat distribution that may affect water releases and habitat improvement projects; and Developing methodologies or decision support tools.

Grantee: Northern Arizona University
Principle Investigators: Matthew Johnson
Cooperative Agreement:  $179,235 in non-Federal funds and $179,236 in Federal funds provided by Bureau of Reclamation


  1. 1. Efficiently realize additional gains from the major capital investment made in data, methods, skills, and other resources during our NCCWSC-supported efforts to develop models that predict the effects of climate change on upland wildlife, with application to riparian species
  2. 2. Link hydrologic, geomorphic, and habitat models to better understand and predict how climate changes will affect critical riparian ecosystems in the region.
  3. 3. Provide management agencies with a decision support tool that provides scientific information required to restore, enhance, and mitigate effects of climate change on riparian vegetation and associated wildlife, as well as identify those areas that may be of greatest risk to predicted changes

Brief Description

Riparian vegetation provides crucial habitat for wildlife and is a high conservation priority for land managers throughout the Southwest but a central scientific challenge is to generate quantitative predictions of how changes in water availability will affect the amount and quality of riparian wildlife habitat.  Researchers  will study areas that  have long-term datasets available (i.e., hydrological, geomorphological, biological), that characterize a broad range of riparian conditions found in the Southwest. Building on recently developed models funded by the USGS National Climate Change and Wildlife Science Center (NCCWSC), this work will link various hydrologic, geomorphic and habitat models to better understand and predict how climate changes will affect critical riparian ecosystems and wildlife in the region.


Lower San Pedro River and the Verde River watershed in Arizona

Project Tasks

  1. 1. Select 2 to 4 bird focal species, and 2 to 4 reptile and amphibian focal species for which there is sufficient data and ecological knowledge to support the development of conceptual models. Candidate bird species include Southwestern Willow Flycatcher, Yellow-billed Cuckoo, Common Black-Hawk, and Gray Hawk. Candidate herpetofauna include Northern Mexican Gartersnake, Canyon Treefrog, Narrow-headed Gartersnake, and Lowland Leopard Frog.
  2. 2. Develop conceptual models to synthesize, represent, and relate relevant life history information about focal species, as a basis for designing and interpreting statistical habitat models.
  3. 3. Build a GIS that contains spatially explicit data on species distributions, downscaled Global Circulation Model (GCM) data, hydrological data, and other candidate explanatory variables identified in conceptual models.
  4. 4. Model wildlife habitat by linking existing hydrologic, geomorphic, and wildlife models to assess how changes in water availability will affect riparian vegetation and riparian-obligate species. Populate the multivariate model with downscaled GCM data to estimate effects on wildlife habitat directly.
  5. 5. Use output from the riparian response model to simulate the effects of different climate-change scenarios on select riparian bird and herpetofauna species habitats.
  6. 6. Produce a set of maps and GIS layers for each bird and herpetofauna species modeled that show in a spatially explicit manner how and where riparian vegetation is expected to change and the resulting impacts to riparian obligate species. These analyses will form the foundation for a decision support system whereby managers can simulate different climate-change scenarios and view the expected results in an interactive website, a product of the NCCWSC project, managed at Northern Arizona University.

Project Deliverables

  1. Select focal species  and develop conceptual models – April 2012
  2. Build GIS – Sept. 2012
  3. Perform Hydrologic modeling using VIC  – Sept. 2012
  4. Model bird and herpetofauna habitat – Feb. 2013
  5. Project future distributions of bird and herpetofauna species– Aug. 2013
  6. Populate decision support tool with results  – Oct. 2013
  7. Write final report - Dec. 2013

Documents to Download

  1. Project Proposal
  2. Performance Report