← Back to all interns
Ellen at final presentations

Ellen Bradley

Gonzaga University

Project: Hot Spots of the Pteropod Limacina Helicina in Puget Sound

My name is Ellen Bradley and I am studying Biology and Environmental Studies at Gonzaga University. This summer, I had the opportunity to participate in a research project through the Joint Institute for the Study of the Atmosphere and Ocean. I worked with Dr. Julie Keister at the University of Washington’s School of Oceanography. The research project we worked on aimed at assessing samples with high abundances of Limacina helicina. Limacina helicina, a species of pteropod, are a type of small microorganism in the ocean. Considering pteropods are an important species of prey, their survival is crucial to the health of Puget Sound. The first step in my research was to verify spatial hot spots of pteropods that had been previously identified by the lab, using the pipette method. The pipette method subsamples, a Ellen on a research cruisesmall volume from a known larger volume. For this reassessment, I subsampled using a Folsom splitter. The Folsom splitter allowed me to observe a larger percentage of the sample than the pipette method. I then counted and measured the pteropods under a dissection microscope. After I characterized all 13 samples, I created a database with the information. I then generated a size-frequency histogram, I calculated biomass (mg carbon / m^3) using size-weight regressions, and correlated biomass between the two methods, in order to verify the hot spots. We also looked at whether pteropods show biomass patterns in relation to deepwater pH measurement. I also participated with the Tulalip Tribes, as they collected samples. While species of zooplankton are an important staple in many marine predators’ diets, little is known about their distribution in Puget Sound. By expanding the data of pteropod distributions, estimates of future assessments may be made, helping to determine necessary steps to promote survival. Many thanks to the Joint Institute for the Study of the Atmosphere and Ocean, the University of Washington School of Oceanography, the laboratory of Dr. Julie Keister, alongside Amanda Winans, and BethElLee Herrmann, the Salish Sea Marine Survival Project, and the JISAO Summer Interns for a great summer!

Ellen's research poster