Southwest Biological Science Center

Filter Total Items: 55
Cattle behind a fence in a dry environment containing few plants and a lot of exposed soil.
Date Published: August 5, 2017

Recovery from disturbance represents a substantial challenge to agencies that manage large tracts of land in the Southwest. Despite the demand for restoration and rehabilitation, little information is available to help managers effectively reestablish native perennial vegetation and stabilize soils, especially given changing climate and disturbance regimes.

Forestry and agriculture have...

Image: A Rainbow Trout Rests Among Cobble Substrate in Panther Creek
Date Published: May 14, 2017

Just below Glen Canyon Dam on the Colorado River is a very popular Blue Ribbon trout fishery known for its rainbow trout. However, approximately 78 miles downstream, near were the Little Colorado River flows into the Colorado River, is a population of endangered humpback chub. The introduced rainbow trout can negatively affect native humpback chub by competing with them for food (immature...

Delicate Arch, a sandstone arch, at Arches National Park
Date Published: April 24, 2017

The objective of this interdisciplinary research effort is to 1) characterize agents of change important to land management decision makers on the Colorado Plateau; 2) identify and analyze relationships between agents of change and key landscape attributes and processes; 3) collectively assess the influence of agents of change and attributes and processes on the services provided by the...

Drill rig in the distance off a dirt road in a semi-aid system.
Date Published: February 28, 2017

Deserts of the southwestern US are replete with oil and gas deposits as well as sites for solar, wind, and geothermal energy production. In the past, many of these resources have been too expensive to develop, but increased demand and new technologies have led to an increase in exploration and development. However, desert ecosystems generally have low resilience to disturbance. More frequent,...

A view of Glen Canyon Dam from the Colorado River
Date Published: February 28, 2017

The overall goal of this project is to advance inter- and trans-disciplinary research coordination, focusing on the transformation of social-ecological systems by hydroelectric dam construction in the Amazon and the United States. The experience gained by Southwest Biological Science Center researchers working on the...

Arizona map depicting the number of bat species found across Arizona.
Date Published: February 14, 2017

Renewable energy development is expanding in southwestern deserts, including in Arizona. Energy developers look to resource management agencies to provide siting guidance on public lands where there might be conflicts with wildlife. Often, agency guidance considers species of conservation concern and economic importance, but information on comprehensive vertebrate biodiversity has been hard to...

Conceptual model about specialist, introduced insects
Date Published: February 13, 2017

Although most introduced insects are relatively benign, some become high-impact pests causing widespread ecological and economic damage. Introduced insects that are specialists and feed on a single genus of plants can be high-impact as they can potentially eliminate an entire native plant genus over large areas. Luckily, most introduced insects with this feeding behavior do not become high-...

Parker Dam on the Colorado River near Parker, Arizona.
Date Published: February 9, 2017

Aquatic invertebrates are critical food for fish and other species that inhabit large rivers. In the Colorado River Basin, invertebrates that get transported down the river (“in the drift”) are particularly important to rainbow trout and other species of interest to recreational users. This research seeks to compare rivers downstream of large dams throughout the Colorado River Basin in order...

Three participants in the Grand Canyon Youth Program looking at a light trap at night near the Colorado River in Grand Canyon
Date Published: January 18, 2017

Aquatic insects are commonly used to gauge the health of stream and river ecosystems, yet collecting enough samples to adequately characterize a river segment as long as the Colorado River through Grand Canyon (> 250 miles) would be essentially impossible using traditional sampling methods. Since 2012, our group has been collaborating with river guides, private boaters, and educational...

A boat on the Colorado River in front of a rock outcrop containing a concrete structure.
Date Published: January 18, 2017

Algae, phytoplankton, and rooted macrophytes represent the base of many aquatic food webs and are known as primary producers. Through photosynthesis, these organisms convert sunlight energy into chemical energy (i.e., carbon) that in turn fuels the growth of animals such as macroinvertebrates and fish. This project uses high frequency measurements of dissolved oxygen, which is a by-product of...

Brown, sediment-laden water of the Paria River mixes with the clear water of the Colorado River
Date Published: December 30, 2016

Sediment controls the physical habitat of river ecosystems.  Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat.  The amount and type of sediment suspended in the water column determines water clarity.  Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...

USGS researcher struggling to set up a line transect (tape measure) in a dense thicket of tamarisk.
Date Published: December 30, 2016

Introductions of bio-control beetles (genus Diorhabda) are causing defoliation and dieback of exotic Tamarix spp. in riparian zones across the western U.S., yet the factors that determine the plant communities that follow Tamarix decline are poorly understood. In particular, Tamarix-dominated soils are often higher in nutrients, organic matter, and salts than nearby soils, and these soil...