Now Archived! PolarConnect event with Lee Teevan and Mary Beth Decker from the R/V Oceanus out of Dutch Harbor, Alaska on 3 August 2017. You can access this and other events on the PolarConnect Archives site.

What Are They Doing?

Photo by Misty Nikula-Ohlsen
A jellyfish on the beach near Barrow, Alaska. Photo by Misty Nikula-Ohlsen.
There is public perception that jellyfish populations are increasing on a global scale. While this may be true for some areas, in the eastern Bering Sea, jellyfish populations have fluctuated dramatically during the past three decades.

This project will estimate the age structure and age-specific abundances of the predominant jellyfish in the Bering Sea, Chrysaora melanaster, in order to understand how their population size changes with time. The ultimate goal is to estimate the reproductive capacity and success of this jellyfish in relation to climate variability and to investigate the potential for jellyfish population increases to become a recurring pattern in the Bering Sea under future climate scenarios. In the Bering Sea ecosystem, key questions are whether increases in jellyfish abundance are a recurring phenomenon under climate change and fishing pressure and how these population increases affect ecosystem structure.

Where Are They?

The R/V Oceanus.
The team will conduct their work aloard the R/V Oceanus in the southeastern Bering Sea.

Latest Journals

In the sweltering heat of an August afternoon in Norfolk, VA, it's hard to fathom what those sub-Arctic temperatures were like a few weeks ago. Although the sensation of cooler air has left me, the experiences I had this summer as a PolarTREC teacher on the research cruise "Jellyfish in the Bering…
The Oceanus is docked at Dutch Harbor, Alaska. Under the heavy fog and misty skies early this morning, the Oceanus quietly meandered to its port at Dutch Harbor. Time, these past nine days, seems to have been compressed and expanded in the bellows of an accordion; moving fast while sampling at a…
Chip Millard, First Assistant Engineer, offers a tour of the Oceanus engine room. The galley, or dining room of the Oceanus, provides a shared meeting space for the crew and science teams. It's a place where we can ask crew members about the ship's technical and mechanical aspects. It was here…
With her spear and magic helmet, Lee tries to guide the CTD onto the ship. Every few hours, the ship slows down and we know it's getting close to the time to start sampling. There are stations, only identifiable by GPS, at which we will use the CTD (conductivity, temperature, and depth)…
R/V Oceanus, Eastern Bering Sea
Project Funded Title
Demographic structure and recruitment patterns of the scyphozoan, Chrysaora melanaster, in the Bering Sea: the influence of climate on ecosystem function
Lenore Teevan - Teacher
Booker T. Washington High School

Growing up in a small town in Ohio, Lenore Teevan biked all over the countryside and wandered the creeks and forests there. Her love of nature and travel has led her to explore places as far as West Africa, as a Peace Corps volunteer, and Japan, as an English teacher. Currently, Ms. Teevan teaches Earth Science and Oceanography at Booker T. Washington High School in Norfolk, Virginia. In addition, she samples water from the Chesapeake Bay as a member of NOAA’s Phytoplankton Monitoring Network. Being able to actively engage in relevant scientific research and inquiry is what motivated her to apply to PolarTREC. Ms. Teevan is looking forward to participating in Arctic research so that she can share a deeper understanding of scientific inquiry with her high school students. She hopes that her firsthand accounts will allow others to view what is involved in ongoing research at sea. She envisions lighting a spark to inspire and motivate her students to pursue university studies and careers in science. Outside of the classroom, Ms. Teevan trains in karate and jiu-jitsu and cycles whenever she can.

Mary Beth Decker - Researcher
Yale University

Mary Beth Decker is a Biological Oceanographer and Ecologist specializing in the influence of ocean conditions on the distribution, abundance, and behavior of marine predators. Mary Beth works on plankton-consuming predators of the Bering Sea ecosystem, in particular jellyfish and forage fish. She is particularly interested in how climate variability influences jellyfish populations, and how jellyfish blooms in turn affect food webs via predation and competition. She teaches three courses at Yale: Biological Oceanography, Coastal Ecosystems in a Changing World, and Caribbean Coastal Development.

Hongsheng Bi - Researcher
University of Maryland Center for Environmental Science

Hongsheng Bi is a Biological Oceanographer specializing in the fine-scale spatial distributions of different marine organisms and their trophic interactions. Hongsheng deploys advanced optical and high-resolution sonar imaging systems to quantify the spatial distributions and overlap of plankton, forage fish and jellyfish. He is particularly interested in how jellyfish affect the spatial and temporal dynamics forage species. Hongsheng’s group operates a towed zooplankton imaging system (PlanktonScope), two adaptive resolution imaging sonar (ARIS) systems and a time-resolved Tomographic Particle Image Velocimetry at the Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science.

Jellyfish in the Bering Sea Resources


Students will understand how the increasing levels of carbon-dioxide in oceans affect shelled marine animals. They will carry out a student-developed investigation on how increasing ocean acidification affects these animals.


The objective of this lesson is for students to assess how increasing levels of atmospheric CO2 affect marine organisms. In addition, they will devise an experiment to test

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Technology geared to the instruction and learning of science concepts, skills, and processes is instrumental to a deeper understanding of science phenomena and content.


This lesson is intended to introduce students to the concept of scientific exploration and investigation. Students will model the technology used in the Jellyfish in the Bering Sea expedition by using underwater cameras and tow

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The Importance of Teacher/Researcher Collaboration

No book, movie or professional development I have experienced could have produced the effect of actually being in the field engaging in scientific research as a PolarTREC teacher on the “Jellyfish in the Bering Sea” expedition July 27-August 5, 2017. As the PolarTREC teacher, I was tasked with the role of disseminating the ongoing

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Teacher Lee Teevan and researcher Mary Beth Decker discuss the science and research behind their expedition aboard the R/V Oceanus looking at jellyfish in the Bering Sea.

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