Southwest Biological Science Center

Fish and Wildlife

Filter Total Items: 27
Date published: December 15, 2016
Status: Active

Status of Northern Leopard Frogs in the Southwest

Although it is not listed on the Federal Endangered Species list, there is considerable concern over northern leopard frog declines in western North America. It is listed as a “special concern” species by some state wildlife agencies (e.g., Arizona Game and Fish Department 1996) and declines have been reported in Arizona, Colorado, New Mexico, and other areas across the west.  Leopard frogs...

Contacts: Charles Drost
Date published: December 15, 2016

Monitoring the Rare Island Night Lizard on San Nicolas Island

The Island Night Lizard was removed from the Federal list of "Threatened" species in May 2014. This rare and unique species represents an ancient lineage whose members are now sparsely distributed across parts of the Southwest North America, south through Mexico to the New World Tropics. The Island Night Lizard has a very small world range, occurring only on three of the southern California...

Contacts: Charles Drost
Date published: December 15, 2016
Status: Active

Economics of Outdoor Recreation

Economic research at Grand Canyon Monitoring and Research Center is used to determine economic benefits of outdoor recreation in Glen Canyon National Recreation Area below Glen Canyon Dam and in Grand Canyon National Park, as affected by operation of Glen Canyon Dam. This research identifies recreationists’ preferences for attributes associated with their trips, spending that occurs regionally...

Contacts: Lucas Bair
Date published: December 9, 2016
Status: Active

Modeling Colonization of a Population of Chiricahua Leopard Frogs

Managing a species with intensive tools like reintroduction may focus on single sites or entire landscapes.  For mobile species like the federally-threatened Chiricahua leopard frog (Lithobates chiricahuensis [CLF]), both suitable colonization sites and suitable dispersal corridors between sites are needed. Following the eradication of the invasive American bullfrog (Lithobates catesbeianus)...

Date published: December 9, 2016
Status: Active

Insect Drift

All aquatic invertebrates drift downstream at some point in their life cycle. Invertebrates may drift to find more preferable habitats, to leave the water during their transition from aquatic larvae to terrestrial adults, or accidentally such as when swept off the river bed by a flood. Regardless, when they enter the drift, invertebrates become particularly susceptible to predation by several...

Date published: December 8, 2016
Status: Active

Turtle Ecology

Turtles are among the most recognizable and iconic of animals. Any animal with a shell and a backbone is a turtle whether they are called turtles, tortoises, or terrapins. In fact, terrapin is an Algonquian Native American name for turtle. Worldwide there are 356 turtle species on all continents except for Antarctica. The United States has more species than any other country with about 62 ...

Date published: December 8, 2016
Status: Active

Grand Canyon Sandbar Monitoring

Since the completion of Glen Canyon Dam in 1963, the amount of sand supplied to Grand Canyon National Park has been reduced by more than 90 percent. The Paria River, a tributary to the Colorado River 15 miles downstream from the dam, is now the single most important supplier of sand to the Colorado River within the Park. This large reduction in sand supply has resulted in substantial decrease...

Date published: December 8, 2016
Status: Active

Adaptive Management

In 1996, the Secretary of the Interior signed a formal decision altering the historical flows from Glen Canyon Dam and establishing the Glen Canyon Dam Adaptive Management Program (GCDAMP). In the context of the management of Glen Canyon Dam, adaptive management was selected to create a process whereby “the effects of dam operations on downstream resources would be assessed and the results of...

Date published: December 8, 2016
Status: Active

Predation of Desert Bighorn Sheep by Mountain Lions in Grand Canyon National Park

Desert bighorn sheep populations in the southwestern United States are subject to non-native disease outbreaks, habitat loss, and genetic isolation that can threaten their long-term sustainability.  In some regions of the southwest, mountain lion predation on desert bighorn sheep has been found to be the primary source of mortality.  Grand Canyon National Park is home to one of the largest...

Date published: December 8, 2016
Status: Active

Wildlife use of Highway Underpasses in Southern California

As a result of growing human populations, many areas have become urbanized and highly developed, leaving natural native habitats fragmented across the landscape.  In southern California many of the remaining patches on native habitat are bisected by major, multi-lane highway systems.  Threats to the long-term sustainability of native wildlife populations include genetic isolation, where...

Date published: December 7, 2016
Status: Active

Desert Tortoise Ecology and Renewable Energy Development

The desert Southwest is experiencing rapid development of utility-scale solar and wind energy facilities. Although clean renewable energy has environmental benefits, it can also have negative impacts on wildlife and their habitats. Understanding those impacts and effectively mitigating them is a major goal of industry and resource managers. One species of particular concern is Agassiz’s desert...

Date published: December 6, 2016
Status: Active

Big Sagebrush Ecosystem Response to Climate & Disturbance

Big sagebrush ecosystems are a major component of landscapes in the western U.S. and provide vital habitat to a wide array of wildlife species.  However, big sagebrush ecosystems have been dramatically impacted by disturbances in the past several decades. This collaborative research between USGS and the University of Wyoming focuses on understanding how climatic and soil conditions influence...

Contacts: John Bradford