About This Project

American Kestrels in the US have declined by 50% in the last 50 years and scientists are struggling to understand why. Increasingly kestrels are reliant on agricultural landscapes, yet little is known about how these landscapes affect their wintering diet. My study will be the first to comprehensively characterize the diet of wintering kestrels using novel genomic tools and will compare diet composition to crop type in order to provide data for both kestrel conservation and sustainable land use.

Ask the Scientists

What is the context of this research?

My study takes place in the Central Valley of California, which is critical to the production of agriculture in the United States and represents an ideal ecosystem in which to study the impacts of differing agricultural crops on the diet of wintering American Kestrels. Environmental DNA (eDNA) metabarcoding is a genomic technique that uses trace amounts of DNA to get a snapshot of the organisms present in a sample collected in a given environment. I will use this technology to characterize the diet of wintering American Kestrels by swabbing their beaks to gather microscopic remains from their previous meals. I will combine the dietary data with agricultural crop type data gathered from GIS to further elucidate the relationship between kestrel diet and human land-use.

What is the significance of this project?

We face a crisis in the loss of global biodiversity, including many avian species which play important roles in ecosystem function. Birds are indicator species of the overall health of our environment and their declines often indicate the failure of human altered landscapes to adequately support biodiversity. Agricultural landscapes increasingly represent the largest habitat available for many avian species in the United States and around the world. Kestrels in particular, are increasingly dependent on agricultural lands and it is important to determine how agricultural practices influence prey selection. This study will provide key insights into the diet of North America’s smallest falcon and inform full-life-cycle informed management strategies in agricultural practices.

What are the goals of the project?

1) Characterize the diet of American Kestrels that utilize the agricultural landscapes of the Central Valley of California as critical wintering grounds.

I will collect eDNA samples by swabbing the beaks of American Kestrels. Using DNA metabarcoding I will identity prey present in the samples (mammals, birds, reptiles, insects).

2) Investigate the relationship between agricultural crop cover and the American Kestrel diet to further understand how human land-use affects kestrel survival.

I will use Arc GIS to characterize information about crop type (orchard, row, and forage) at the location of of each eDNA sample taken and compare that to the prey species detected at each site.