Unified Interior Regions


The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

States L2 Landing Page Tabs

Filter Total Items: 140
Date published: November 29, 2016

Science to Inform Riparian Ecosystem Restoration and Management

Throughout the world, riparian habitats have been dramatically modified from their natural condition. Dams, non-native species and climate change are often principal drivers of these changes, via their alteration of water and sediment regimes that determine key resources for riparian plants.

Date published: November 29, 2016

Large-scale streamflow experiments

Because the underlying cause of riparian system alteration is often attributed to the effects of dams on flow regime, managing flow releases, particularly high flows, from dams is an often-advocated approach to river and riparian restoration. Our work has focused on understanding effects of managed high flow releases (a.k.a., pulse flows, controlled floods) from dams along rivers in the lower...

Date published: November 28, 2016
Status: Active

Biological Invasions of Riparian Ecosystems

Beginning in the early twentieth century, non-native trees and shrubs, including tamarisk (also commonly known as saltcedar) and Russian-olive, were introduced to the United States for use as ornamental plants and in erosion-control plantings. These plants spread extensively, becoming the third and fourth most frequently occurring woody riparian plants in the American West.


Date published: November 28, 2016

Streamflow-fluvial Geomorphology-riparian Vegetation Interactions

The foundation for applying science to river and riparian restoration contexts lies in a basic understanding of the factors that drive riparian vegetation dynamics. Much of our research is focused on clarifying relationships between streamflow, fluvial geomorphology, and riparian vegetation, including various feedbacks.

Date published: November 21, 2016

Status and Breeding Ecology of the Arizona Grasshopper Sparrow

The Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) is a disjunct race that breeds in desert grasslands of southeastern Arizona, extreme southwestern New Mexico, and adjacent parts of northern Sonora and Chihuahua, Mexico.

Date published: September 23, 2016
Status: Active

The New Mexico Landscapes Field Station

The New Mexico Landscapes Field Station is a place-based, globally-connected, ecological research group that studies and interprets ecosystem and wildlife dynamics, working with land managers and community leaders to deliver solutions that foster the linked health of human and natural systems.

Our partnerships, and co-location, with land management agencies provide us with opportunities...

Date published: September 21, 2016
Status: Active

External Microbiota of Bats as Potential Bio-control Against Wildlife Diseases

White-nose syndrome (WNS) and/or Pseudogymnoascus destructans (P.d.), the causal agent, has spread westward across 26 states and 5 provinces within the eastern United States and Canada, respectively, over a short period of time. Since its discovery there has been a search to stop the spread of this disease that has killed millions of hibernating bats in its wake. Recent collaborative work by...

Date published: September 20, 2016

Post-fire Recovery Patterns in Southwestern Forests

High-severity crown fires in Southwestern dry-conifer forests — resulting from fire suppression, fuel buildups, and drought — are creating large treeless areas that are historically unprecedented in size. These recent stand-replacing fires have reset extensive portions of Southwest forest landscapes, fostering post-fire successional vegetation that can alter ecological recovery trajectories...

Contacts: Collin Haffey
Date published: August 30, 2016

New Mexico Dendroecology Lab

Using tree ring analysis as a primary research tool, we conduct landscape-scale ecological research that focuses on the effects of climate variability on forest ecology, fire ecology, and ecohydrology. 

We are the only tree-ring lab in New Mexico, working in close collaboration with Bandelier National Monument and Emeritus Regents’ Professor Dr. Thomas Swetnam.  However, we were not the...

Date published: August 29, 2016
Status: Completed

Study Reveals Processes that Control Uranium Bioavailability in a Freshwater Snail—Relevance to Aquatic Biota in the Grand Canyon Area

Scientists refined an existing speciation model to identify key biogeochemical processes controlling dissolved uranium bioavailability to a freshwater snail. This information is important to advance current understanding and prediction of the ecological risk posed by uranium mining to freshwater ecosystems, including federally managed lands such as in the Grand Canyon area.

Date published: August 1, 2016
Status: Active

Ecology of Insect-eating Bats

Bats are the only flying mammals that are active mostly at night and occur on all continents except Antarctica. Bats are ecologically diverse, with a range of species that specialize in feeding on fruit, nectar, blood, fish, small mammals, and insects. However, of the more than 1,100 known species of bats on Earth, the majority specialize in feeding on insects. In the United States for example...

Date published: July 26, 2016
Status: Active

HDgov: Multi-agency Website for Human Dimensions of Natural Resources

HDgov is an interactive and mobile-responsive online portal to interagency, academic, and non-government resources focused on the human dimensions of natural resource management. The web portal provides easy access to tools, publications, data, and methods that help ensure that the people side of natural resources is considered throughout the entire natural resource management process. The...

Filter Total Items: 240
September 30, 2012


Working at the USGS can be fun. These student employees were given wonderful opportunities and made lasting friendships while working at the USGS.

September 12, 2012

Continuous Slope Area Method: Sycamore Creek, AZ

A video depicting the installation & operation of Continuous Slope Area gage and radar sensor, installed after the Sunflower Wild Fire on Sycamore Creek to measure streamflow from the Sunflower burned area. The streamflow data is used to provide flood warning to communities affected by runoff from the burned areas and for collecting streamflow data from areas that have

July 5, 2012

2012 Whitewater-Baldy Fire

USGS installed six early-flood-warning units—rain and stream gages—in the burned areas resulting from New Mexico's 2012 Whitewater-Baldy Fire. The gages transmit data via satellite to provide warnings to communities that may be affected by flooding.

October 2, 2011

Nat'l Comparison of USGS Compiled Irrigation Water Use Data

Highlights of the Scientific Investigations Report 2011-5166 which documents methods of irrigation and inventories irrigation data collected for the 2000 and 2005 U.S Geological Survey.

Valles Marineris on Mars
September 29, 2011

Valles Marineris on Mars

Mosaic of the Valles Marineris hemisphere of Mars projected into point perspective, a view similar to that which one would see from a spacecraft. The distance is 2500 kilometers from the surface of the planet, with the scale being .6km/pixel. The mosaic is composed of 102 Viking Orbiter images of Mars. The center of the scene (lat -8, long 78) shows the entire Valles

August 10, 2011

Post-fire Flash Flood in Coronado National Memorial, Arizona

Video footage begins with dry streambed, and within the first 10 seconds a very dark, roiling, flow comes downstream toward the viewer. The rest of the video is footage of the flow going past, and into a culvert under a bridge. The video was recorded at the U.S. Geological Survey streamgage site near the Coronado National Memorial visitor center, in southern Arizona. The

Image: Landsat Photo: Wallow Fire, Arizona
June 7, 2011

Landsat Photo: Wallow Fire, Arizona

This Landsat imagery was taken on June 7, 2011. Path/Row: 35/36 and 37 Lat/Long: 33.820/-109.330

Image: Drilling in Cinder Lake, Arizona
June 3, 2011

Drilling in Cinder Lake, Arizona

Boreholes being drilled at Cinder Lake as part of a U.S. Geological Survey study to determine the feature's floodwater storage capacity. Cinder Lake, which is located on the Coconino National Forest, has been used to store runoff from areas affected by the 2010 Schultz Fire outside of Flagstaff, Arizona.

Attribution: Natural Hazards
May 5, 2011

Electronic Tape Calibration Procedure

A training video discussing how to calibrate the electronic tape.

May 5, 2011

Microgravity Measurement for Groundwater Analysis

A video discussing the Gravity Meters used at the USGS Arizona Water Science Center.

Image: Dust Storm Near Winslow, Arizona, in April 2011
April 1, 2011

Dust Storm Near Winslow, Arizona, in April 2011

Dust carried by the wind has far-reaching effects, including the loss of nutrients and water-holding capacity from landscapes, and the speeding up of the melting of snow, which affects the timing and magnitude of runoff into streams and rivers.

Attribution: Land Resources
Filter Total Items: 192
USGS science for a changing world logo
May 20, 2009

The U.S. Geological Survey will conduct scientific overflights at Grand Canyon National Park, Arizona, during Memorial Day weekend to document the status of natural and cultural resources along the Colorado River below Glen Canyon Dam. Aerial photographs will be taken using two fixed-wing aircraft flying at an elevation about 7,000 feet above ground level.

USGS science for a changing world logo
April 27, 2009

Adult endangered humpback chub (Gila cypha) in Grand Canyon, Arizona, increased by about 50 percent between 2001 and 2008, according to analysis recently conducted by the U.S. Geological Survey. The upward trend reverses population declines from 1989 to 2001. 

USGS science for a changing world logo
April 24, 2009

U.S. Geological Survey scientists will brief reporters by phone at 3:00 pm Eastern Daylight Time/12:00 pm Mountain Standard Time. Monday, April 27, on the latest population numbers for the humpback chub (Gila cypha) in Grand Canyon, Arizona.

USGS science for a changing world logo
March 2, 2009

Volunteers across the nation are being recruited to get outdoors and help track the effects of climate on seasonal changes in plant and animal behavior.
The USA-National Phenology Network (USA-NPN), a consortium of government, academic and citizen-scientists, is launching a new national program built on volunteer observations of flowering, fruiting and other seasonal events.

USGS science for a changing world logo
February 25, 2009

Unique fractures in lavas on ancient Mars suggest water occasionally flooded portions of the planet's surface.
The fractures, known as "columnar joints", are the first that have been observed on a planet other than Earth.

USGS science for a changing world logo
February 12, 2009

Astrogeologists at the U.S. Geological Survey in Flagstaff provided critical datasets used in the latest release of Google Earth. The updated software enables users to explore Mars in high detail.
"Without the ability to accurately co-align data sets, applications like Google Earth would not be nearly as useful," said Trent Hare, a GIS expert with the USGS Astrogeology Team.

USGS science for a changing world logo
December 18, 2008

Dr. Julio Betancourt, a U.S. Geological Survey senior scientist, was recently awarded a prestigious 2008 Presidential Rank Award. Betancourt, who has conducted groundbreaking research in how climate variability affects ecosystems, is also an adjunct professor at the University of Arizona, where he received his graduate degrees.


October 9, 2008

Local planetary geologist Chris Okubo is on a mission to understand the past roles of groundwater and faulting on Mars by studying similar locations on Earth.  Okubo works in the Astrogeology Research Program for the U.S. Geological Survey (USGS) in Flagstaff.

June 17, 2008

Long-term trends in landscape conditions have significantly reduced sagebrush habitat and populations of greater sage-grouse, according to a new study examining the bird's chances of survival.

April 21, 2008

The Upper San Pedro Partnership was recognized with the Department of the Interior's Cooperative Conservation Award today.

April 7, 2008

Time lapse videos of sandbars from the Glen Canyon Dam high flow experiment have been released by the U.S. Geological Survey (USGS).

March 18, 2008

Competition for water is becoming more intense as the nation's population continues to grow, increasing the demands for water use in agriculture and power production.