Demi Berceau organizing the organs in separate containers during dissection for logging purposes
Authors: Katherine Brown, Reece Mullen, Demi Berceau, Rachel Martin, Nathalie Barahona. Edited by Sarah A. Orlofske, PhD, Assistant Professor & Curator of Animal Parasites, Associate Editor Ecology, Epidemiology, Survey and Behavior, Journal of Parasitology, University of Wisconsin – Stevens Point
This article originally appeared in Wisconsin Waterfowl Association’s January 2020 Newsletter edition and is an update to Of Waterfowl and Parasites published in September 2019.
Reece Mullen, Katherine Brown and Nathalie Barahona analyzing internal organs
During this duck hunting season many hunters harvested the breast of the ducks they hunted, but had no use for the rest of the carcass. These carcasses, despite not having much value for the average hunter, can be very useful for a variety of researchers. One group of researchers are undergraduate students at the University of Wisconsin – Stevens Point. These students are taking the parts of the duck that would normally go to waste to look at the parasite abundance, and parasite diversity (number of different species), across the waterfowl species. This information helps us better understand parasite-host interactions, but can also help manage duck populations and their potential diseases.
Katherin Brown preparing the intestines to obtain parasites
Spanning this year’s waterfowl season, a team of five students at UWSP joined Dr. Sarah Orlofske specifically to survey the parasites of local waterfowl, primarily scaup. It is possible to learn a lot about an individual bird and, possibly, the population and ecosystem, by the parasites they carry. Understanding the birds’ diet or habitat are just some of the things that can be determined by an organism’s parasite load. To accomplish this, research students carefully process each bird. The research team’s process of finding the parasites consists of ruffling the feathers of the bird for ectoparasites, as well as searching the internal organs throughout the entire bird. The research team uses standard parasitological methods to isolate and identify the types of parasites using dissecting microscopes. So far, they have dissected a total of nine birds; including five lesser scaup, one greater scaup, two common goldeneye and one long-tailed duck.
Inside of intestines, sometimes parasites are big enough to be seen by the naked eye here
The average number of parasites found per bird was sixty-seven, with a male lesser scaup having the most at a total of 130 parasites. In addition, some of the different types of parasites found this far in the research include tapeworms, lice, flatworms, as well as some less common ones. There seems to be a trend of male birds having higher amounts of parasites then the female birds, but more research is needed. The team has been carefully counting, logging, and storing the parasites by taxonomic groups in hopes of learning more about their potential species diversity and if they are consistent among scaup and between the various waterfowl species.
Rachel Martin using a dissection microscope to draw up and separate found parasites
As for the future, the research team continues to grow in members and has hopes of continuing into next semester. Each student tends to focus on their own parasite species or a part of the bird that excites them. The greatest hope is discovering a parasite that wasn’t classified yet and being able to learn more about them.