Grad student blogs on one of Rice Rivers's Center primary avian reserach programs
March 22, 2016
by Jessie Reese
The motor of our small fishing boat hums as we travel up a stream bisecting a narrow peninsula of red mangrove forest called Bocas del Atrato, in a remote region of the Caribbean coast of Colombia. We glide past massive mangrove prop roots and lush foliage, and come to stop along a patch of terra firma. A Common Black Hawk eyes us warily from an overhead perch as a chorus of howler monkeys lends an ominous feeling to the dawn. I ready my clipboard for a standardized bird survey and set my stopwatch for 10 minutes. It’s not long before I see a flash of brilliant yellow, and hear the distinctive chip note of a Prothonotary Warbler. I’ve followed this species from its temperate summer breeding grounds to its wintering habitat in the Neotropics, where I hope to unravel some of the mysteries of its poorly known winter ecology.
During the summer, Prothonotary Warblers are found in forested wetlands throughout the eastern U.S. and southern Canada, including at VCU’s long-term study site in the Lower James River Important Bird Area. For the winter months, Prothonotaries migrate to Central and northern South America, where highest concentrations are found in coastal mangrove forests. With funding from the Riverbanks Conservation Support Fund and the Northern Neck Audubon Society, I traveled with Alessandro Molina (B.S. Biology, VCU ‘14) and Dr. Lesley Bulluck on a month-long expedition to study Prothonotary Warblers overwintering Colombia. There we partnered with Dr. Nick Bayly and Angela Caguazango from SELVA: Research for Conservation in the Neotropics, a Colombian non-profit research institute with a focus on migratory bird ecology. Our goals were to conduct density surveys to determine where the birds are most abundant, to capture birds and collect feather samples, and to quantify habitat associations.
Our trip spanned over 700 miles of the Caribbean coast. We visited four mangrove forests and one freshwater lagoon, conducting a total of 70 density surveys and collecting 115 feather samples. As we traversed between sites, the humid lowland forest on the border of Panama transitioned to dry tropical forest in the east, where the landscape was peppered with cacti. Our expedition was a success, not only in terms of the data we collected but also through the connections we made to local people and places. Guides from the community shared their knowledge of local flora and fauna, and biologists from the Sistema de Parque Nacionales Naturales told us about their conservation successes and challenges. Leaving Colombia’s rich avifauna and welcoming culture was bittersweet, but almost as exciting as collecting the data will be understanding the story it can tell us. Working with my graduate thesis advisor Dr. Bulluck, I will analyze isotope ratios in the feathers we collected, which will help determine how populations are geographically linked between seasons. Ultimately, we hope to use our increased knowledge of Prothonotary Warbler ecology to inform management strategies and promote full life-cycle conservation, a goal which will certainly be advanced by the partnerships we made during this expedition.