March 19, 2012 by Melisa P. Danho, NMSU News Center
Holloman Air Force Base is often booming with F-22s and bustling with pilots and personnel, but does all this activity have an effect on the wildlife covertly cohabitating with the airmen? New Mexico State University researchers aim to find out.
Kenneth Boykin is a research associate professor for the Department of Fish, Wildife and Conservation Ecology at NMSU working with Nicole Harings, a doctoral candidate in the biology department. Boykin and Harings are preparing to take an inventory of reptile species on Holloman and will catalogue reptiles that are creeping, crawling and slithering around the different habitats that exist on the base.
“There are probably close to 50 species of snakes and lizards that we might see,” Harings said. “We’ll probably see a lot of whiptail lizards and rattlesnakes. We’ll also be looking for the Texas horned lizard as a focal species.”
In previous studies, Boykin and other researchers at NMSU have only noted a few observations of the Texas horned lizard at Holloman. The Texas horned lizard is a sensitive species known to be declining across its range due to habitat alteration, overcollecting, and fire ants that negatively impact prey essential to the lizard’s survival. Boykin said further investigation into lizard populations is necessary because there is still some uncertainty regarding its status and threats.
Since the Texas horned lizard is a sedentary creature the best technique to monitor it may be road cruising, where researchers simply drive slowly and look for lizards basking on the roads or waiting for approaching prey.
There are of course other species that researchers will be documenting. The different types of habitats at Holloman including grasslands, sand dunes and areas with lots of shrubbery contribute to the potential diversity of reptilian life. This also means different trapping methods will have to be used in order to identify species including pitfall and funnel traps.
Pitfall traps use a pit dug in the ground where animals can fall and cannot escape. Funnel traps are often used in conjunction with a drift fence, or a makeshift wall about a foot or two in height, that forces the animal to crawl along it, seeking an opening. The opening they find is in the form of a funnel-shaped trap and reptiles often find difficult to escape.
The researchers will set up a minimum of 30 to 40 sampling units and the traps will be set before dark and checked the next morning. The species will be identified, measured and weighed, in order to obtain an approximate age. Their gender will also be noted as well as the environment in which the species was found.
“It’s really a proactive approach,” said Boykin. “We want the Air Force to have the information when planning their missions and activities, so they’re aware of the environment and won’t cause detrimental effects to any species, especially rare species.”
The data collected by researchers will be transformed into meaningful information by the use of techniques, like logistic regression, a statistical methodology used to predict binary responses, such as whether a particular species is normally found in a specific habitat. The wildlife researchers may also collaborate with William Gould, an NMSU applied statistics professor who has experience with occupancy modeling, a relatively new methodology that uses presence/absence data surveys while accounting for imperfect detection.
The purpose behind using these statistical methods is to measure species richness and abundance of various species. Richness refers to the number of species occupying a particular landscape and relative abundance refers to the percent of the landscape that a particular species occupies.
“Ultimately, we want to identify ways decision makers at Holloman can make sure species’ habitats are conserved and the environment is maintained while the Air Force continues their missions,” Boykin said.