Southwest Biological Science Center


The Southwest Biological Science Center (SBSC) conducts quality, objective research on the lands and aquatic systems of the Southwest. This research can assist those who manage, conserve, and rehabilitate the arid regions of the nation. Click on SCIENCE in the sidebar to the left to explore SBSC science in more detail.

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Terrestrial Dryland Ecology Branch

Terrestrial Dryland Ecology Branch

The Terrestrial Dryland Ecology (TDE) Branch of the SBSC studies the biology, ecology,and processes of semi-arid and arid lands (known as drylands). TDE researchers study plant-soil-water relationships and the wildlife found in drylands.

TDE Science

River Ecosystem Science Branch & GCMRC

River Ecosystem Science Branch & GCMRC

The River Ecosystem Science (RES) Branch of the SBSC, which includes the Grand Canyon Monitoring and Research Center (GCMRC), studies the biology, ecology, and processes of rivers in the western United States, with an emphasis on the Southwest.

GCMRC & RES Science


Date published: February 4, 2021

RAMPS NEWSLETTER - Winter 2021 Edition

Restoration Assessment and Monitoring Program for the Southwest (RAMPS)

A Program of the Southwest Biological Science Center & Ecosystems Mission Area

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Date published: November 24, 2020

Friday's Findings - December 4 2020

The Smart Energy Webtool: Providing Relevant and Accessible Information to Support Energy Development and Management

Date: December 4, 2020 from 2-2:30 p.m. eastern time

Speaker: Mike Duniway, Research Ecologist/Soil Scientist, USGS Southwest Biological Science Center



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Year Published: 2021

The Transformation of dryland rivers: The future of introduced tamarisk in the U.S.

Tamarix spp. (tamarisk or saltcedar), a shrub-like tree, was intentionally introduced to the U.S. from Asia in the mid-1800s. Tamarisk thrives in today’s human-altered streamside (riparian) habitats and can be found along wetlands, rivers, lakes, and streams across the western U.S. In 2001, a biological control agent, Diorhabda spp. (tamarisk leaf...

Nagler, Pamela L.; Hull, Julia B.; van Riper, Charles; Shafroth, Patrick B.; Yackulic, Charles B.
Nagler, P.L., Hull, J.B., van Riper, C., Shafroth, P.B., and Yackulic, C.B., 2021, The Transformation of dryland rivers: The future of introduced tamarisk in the U.S.: U.S. Geological Survey Fact Sheet 2020–3061, 6 p.,

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Year Published: 2021

Gopherus Agassizii (Agassiz’s Desert Tortoise). Overwinter movement

No abstract available.

Cummings, Kristy L.; Lovich, Jeffrey E.; Puffer, Shellie R.

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Year Published: 2021

‘Unscrambling’ the drivers of egg production in Agassiz’s desert tortoise: Climate and individual attributes predict reproductive output

ABSTRACT: The ‘bet hedging’ life history strategy of long-lived iteroparous species reduces short-term reproductive output to minimize the risk of reproductive failure over a lifetime. For desert-dwelling ectotherms living in variable and unpredictable environments, reproductive output is further influenced by precipitation and temperature via...

Mitchell, Corey I.; Friend, Derek A.; Phillips, Lauren T.; Hunter, Elizabeth A.; Lovich, Jeffrey E.; Agha, Mickey; Puffer, Shellie R.; Cummings, Kristy L.; Medica, Philip A.; Esque, Todd C.; Nussear, Kenneth E.; Shoemaker, Kevin T.