NAU professor to study bird habitats, dangers on military bases

FLAGSTAFF, Ariz. — The U.S. Department of Defense owns military installations on nearly 27 million acres accross the country—roughly equivalent in size to Virginia—and oversees these lands through a network of natural resource managers.

One of the program’s top priorities is monitoring and maintaining populations of threatened and endangered species of birds—especially those that eat insects and other arthropods like spiders, which have been particularly hard hit.

Associate Professor Jeff Foster of Northern Arizona University’s Department of Biological Sciences and the Pathogen and Microbiome Institute recently was awarded a 3-year, $900,000 grant by the Department of Defense to study five insectivorous bird species on four military sites.

These birds include the golden-cheeked warbler, black-capped vireo, least Bell’s vireo, golden-winged warbler and Oahu elepaio.

Monitoring the quality of the birds’ habitats, including their typical diets of insects, is one of the most important ways scientists investigate declining bird populations. The tools the military land managers use to assess diets and habitats are crucial, but the current methods of measuring habitat quality related to the birds’ food resources are time consuming, expensive and require specific biological expertise.

Bioinformatics, metabarcoding

The team will collect fecal samples from the birds and arthropod samples and perform bioinformatic and chemical composition analyses.

They will validate the technology by comparing it to conventional methods, develop guidance documents and lead hands-on technical workshops for the military land managers.

Foster said this will be the most in-depth diet analysis of birds on military installations done to date.

The study will use metabarcoding, which is a technique that enables scientists to identify multiple species of plants or animals on a large scale based on rapid, high-throughput environmental DNA sequencing, which represents a major technological step forward.

“We’ll assess habitat quality by using advanced genetic approaches to measure arthropod food resources in bird diets and from the vegetation on which these birds forage,” Foster said. “Our three primary objectives are to demonstrate the effectiveness of metabarcoding of bird diets and food resources; compare this genetic approach to conventional approaches that employ visual identification of arthropods using microscopes; provide user-friendly analytical software.”

Collaborators include military scientists and undergraduate researcher Foster will work closely with co-principal investigators Jinelle Sperry and Aron Katz from the U.S. Army Corps of Engineers Engineer Research and Development Center’s Construction Engineer Research Laboratory, as well as with collaborators at each of the installations.

NAU undergraduate researcher Hannah Brosius is working on the project with Foster and PMI researcher Alexandra Gibson. Brosius, who will be assisting with the lab work and analyses, said, “I’m excited about this project because the analysis of bird diets from feces will help us figure out why these endangered birds might be at risk. It’s fun to be able to take a fecal sample from a species; you can learn a lot using DNA to understand how an animal lives.”

She is looking forward to her future as a veterinarian. “I’m interested in lab work, which allows me to focus on a project and have results quickly. This research experience will be important for veterinary school and will expand my understanding of biology.”

Project to benefit TES monitoring across DoD sites

The project’s outcomes will have multiple benefits that will help DoD land managers monitor threatened and endangered species.

“It’s an effective and cost-efficient way to measure habitat quality, particularly as it relates to a key factor regulating insectivorous bird abundance—arthropod food resources,” Foster said. “The technology can be deployed at any DoD site where understanding diet or habitat quality is necessary for TES monitoring of vertebrate taxa. Population surveys can assess the current abundance and distribution of TES but determining the specific factors limiting their populations adds additional complexity. This method will not only give DoD natural resource managers the ability to distinguish poor versus high-quality habitat, but will provide critical information about restoration, habitat recovery from disturbance and a baseline of prey availability should arthropod populations decline regionally in the future.”

In addition, numerous other bird species are on the list of DoD Priority Species and could benefit from this technology as well as other taxa such as amphibians, reptiles and small mammals.

Information provided by NAU.