Current Projects

Waterfowl wintering at the Upper Ouachita NWR in NW Louisiana

Metal Contaminants in Wintering Waterfowl

Studies of captive waterfowl have shown that metal contamination can adversely affect their body condition.  Poor winter body condition may negatively affect survival and reproduction.  We are examining metal contaminants in tissues of ducks donated by hunters hunting in Wildlife Management Areas in Louisiana. Birds are known to sequester metals in their feathers, Since the feathers of ducks wintering in Louisiana are grown on their summer breeding grounds, we can disentangle contaminants that may have accumulated in tissues at different life history stages. Species that feed at different trophic levels may be expected to accumulate metals at different rates.

Avian Survival and Production in a Restored Short Leaf Pine Community

Upland short leaf pine communities were essentially eradicated in Louisiana, but, with the cooperation of The Nature Conservancy and landowner Dr. Johnny Armstrong, a 400-acre area is being restored at Wafer Creek Ranch in Ruston, Louisiana. It will be important to monitor the presence and performance of species in the area as the restoration progresses.

Old growth short leaf pine at Wafer Creek Ranch

A controlled burn at Wafer Creek Ranch

Feather grass growing at Wafer Creek Ranch after a controlled burn

Nazca Booby parent and offspring

Reproductive Senescence

Birds are often long-lived, despite higher metabolic rates and total lifetime energy expenditures, body temperatures, and blood glucose levels, compared to mammals of equivalent mass. Under the disposable soma theory of aging, elevation of these parameters in birds should accelerate damage to cells, proteins, and DNA from the accumulation of deleterious by-products of metabolism. Study of aging processes in
long-lived wild seabirds offers an important perspective on mechanisms involved in aging across taxa, including humans. With collaborators from Wake Forest University and University of Houston, we are investigating reproductive and actuarial senescence in Nazca boobies using serum samples to track biomarkers of health, stress, and immune function across lifespan. .

Nesting Loggerhead Shrike

Historic Avian Nesting Distributions in Louisiana

Ornithology classes at Louisiana Tech, from the 1960s through the 1980s, collected information about nesting birds in Louisiana. We are digitizing this information to determine the historic nesting ranges of birds in our area. This information can be used to see how the reproductive success and distribution of species has changed over time.

Organophosphate degrading microbes

Organophosphates are one of the most widely used insecticides and are used in agriculture, home gardens, and veterinary practice. They can also be used as chemical nerve agents. They function by interfering with acetycholine signaling in the body. Once these compounds enter the environment they can have ill effects in non-target organisms, including humans. We are searching for soil microbes that are capable of degrading these pesticides. These microbes could be used for bioremediation of contaminated sites.

Soil samples

Microplastic fiber found in GI Tract of a Blue-winged Teal

Microplastic ingestion by waterfowl

The Mississippi River and the Gulf of Mexico have some of the highest concentrations of plastic particles among aquatic ecosystems worldwide. Ingestion of microplastics can have deleterious effects on growth, reproductive success, and behavior. Yet little is known about microplastic ingestion by biota found in the Gulf of Mexico region. We are examining microplastic ingestion by waterfowl in ducks donated to us by Louisiana hunters.