From Denton to Greenland, UNT researchers investigate endangered species and wildlife threats
From investigating declining bumblebee populations to determining the effects of flooding and climate change on reptiles, UNT animal conservation research is making a difference around the world.
UNT students have the opportunity to learn about conservation through the university's new Ecology for Environmental Science bachelor's degree program. The program is the only one of its kind in the Dallas-Fort Worth area, and adds to UNT's history of education and research programs related to ecology, conservation and environmental science.
North Texas bumblebees
Bumblebee populations are declining across the U.S., which causes concern among conservationists because bumblebees are the primary pollinators for several types of flowers and food crops, including tomatoes and chili peppers.
Jessica Beckham, a UNT graduate student working on her Ph.D. in environmental science, is nearing the end of a long study documenting North Texas bumblebee populations. Beckham began her project by investigating the history of bumblebees in Denton County using specimens from UNT's Elm Fork Natural Heritage Museum.
She also spent time across Denton County documenting different bumblebee species to determine whether the local population is declining and whether or not urban development is driving the bees toward rural areas. She also investigated the status of current populations, as well as the extent to which they are using Denton's existing urban community gardens and green spaces as habitat.
In the process, Beckham sampled 450 individual bees and found two declining species, the American bumblebee and the Southern Plains bumblebee. Notably, the Southern Plains bumblebee hadn't been documented in Denton County for 15 years.
"Our results show that urban green spaces are providing important habitat for our declining bumblebee species," Beckham says. "By incorporating green spaces into our cities, we may be able to mitigate some of the habitat loss associated with urban sprawl."
Beckham will extend her study across 16 other Texas counties in 2014 thanks to a State Wildlife Grant from the Texas Parks and Wildlife Department.
Environmental impact on reptiles
Dr. Dane Crossley, assistant professor of biology, focuses his research on understanding developmental physiology in animals, including birds, amphibians and reptiles. In particular, he explores how environmental surroundings affect cardiac health in animals.
Environmental issues that may affect an animal's long-term cardiac health include climate change and flooding.
"We are investigating how environmental changes, such as those that occur with climate change, affect American alligators," Crossley says. "The developmental environment impacts several embryonic processes, such as gender which is determined by temperature at a certain phase of alligator development. As an example, if average temperatures were to rise above a critical point, all alligators could develop as the same sex, which is a threat to the species."
The questions Crossley is investigating will help scientists understand how environmental changes in the early stages of life may impact animals as juveniles and adults. Developing that understanding, and being able to predict outcomes in response to environmental stress for a given species, will be useful for potential species management issues in the future.
UNT Quail is an innovative game bird preservation program and research laboratory at UNT working to preserve threatened North Texas quail populations. Dr. Kelly Reyna, assistant professor of biology and executive director of UNT Quail, works with students on a number of outreach and conservation projects each semester.
Projects include speaking with individuals and groups, such as hunting organizations, across the region to provide information on how landowners can make their property friendlier to quail, as well as capture and release trips to relocate quail to safe areas in North Texas.
"Quail have a lot of natural predators and threats," Reyna says. "By taking smaller, more vulnerable quail populations and linking them to larger groups, quail populations become more resilient and are better able to withstand stressors, including heat, for example."
Reyna's research interests include the ecology, genetics, physiology and population dynamics of northern bobwhite quail, prairie chickens and other game birds.
Woodpeckers in southern Chile
Jaime Jiménez, biology professor, focuses a portion of his research on birds in the Cape Horn Biosphere Reserve in southern Chile. For one of his projects, Jiménez researches Magellanic woodpeckers, which have seen recent declines in population. Magellanic woodpeckers are a close relative of ivory-billed woodpeckers, which are extinct.
Jiménez and his research team recently discovered a new threat to the region's Magellanic woodpecker population: Mink.
"Mink began being released from farms into the wild in the 1930s on the mainland and invaded the Cape Horn Region in the '90s," Jiménez says. "They are efficient predators, and recently, using telemetry data, motion-activated camera photos to direct observations, we have seen evidence leading us to believe the mink are preying on the woodpeckers," Jiménez says.
Mink reproduce quickly, and woodpeckers do not. If the situation isn't taken under control soon, woodpecker populations could decline and become locally extinct, he says.
Along with his research projects, Jiménez also leads a winter study abroad program at the reserve each year, where UNT, along with Universidad de Magallanes and the Institute of Ecology and Biodiversity, have a field station and a research, education and conservation area.
Birds of prey and grouse
Jeff Johnson, assistant professor of biology, is interested in how human actions have impacted species throughout the world. His research team focuses primarily on the conservation of grouse and birds of prey, such as the Attwater's Prairie-chicken in Texas and the Oriental White-backed Vulture in India and Pakistan. Both species are critically endangered with fewer than 50 Attwater's remaining in the wild and a 99 percent decline observed among Oriental White-backed Vultures from more than a million as little as 20 years ago.
Recent work in Johnson's lab identified a large number of errors in the pedigree used to assign breeding pairs in the captive Attwater's Prairie-chicken population.
"These kinds of errors in pedigrees are not uncommon, but when they accumulate to high levels it becomes increasingly difficult to minimize inbreeding depression, which is what happened in this case," Johnson says.
Changes were made to the pedigree to address the errors and help strengthen the Attwater's population as a result.
Similar applications were conducted with the Oriental White-backed Vulture were Johnson helped establish a captive breeding program for the species, while creating an accurate pedigree to minimize inbreeding in the population.
Johnson also studies multiple bird species in Greenland, including the Gyrfalcon and Peregrine Falcon, Arctic Tern, Dovekie and Eiders. The work in Greenland is primarily focused on how species have evolved to persist in an extremely harsh environment and how recent changes in climate and habitat may impact those populations.