A Summer of Polar Bear Research

Defenders of Wildlife is partnering with the Alaska Native Science and Engineering Program (ANSEP) to sponsor students to perform polar bear research in Alaska. ANSEP reaches out to Alaska Native students from middle school and beyond to encourage them to pursue STEM degrees, offering their students a strong community connection, as well as financial support towards their degree. We were very pleased to have Vanessa Muhlenbruch as the sponsored student in this program for the summer of 2016.

Being a born and raised Alaskan who has spent her whole life in Anchorage, attending the University of Alaska Anchorage (UAA) seemed like a natural choice. I was able to stay near my friends and family during my undergraduate career, and I also got to be a part of the Alaska Native Science and Engineering Program (ANSEP), a program that has had a profound impact on my undergraduate experiences. I first became connected with ANSEP during the summer following my senior year of high school, when I participated in “Summer Bridge.” This is one of ANSEP’s pre-college components that helps incoming students prepare for their first semester of college by providing a college math course, a paid professional internship, and financial support for their undergraduate years at UAA. Four years later, I now have a Bachelor’s of Science degree in Biology, and so many amazing experiences including my internship opportunity with the United States Geological Survey (USGS).

As a biology major, USGS had never been on my radar. With geological in the title and no knowledge of the research USGS did, I didn’t think they’d have any work for me. So when two branch chiefs from USGS’s Alaska Science Center came in to speak at one of ANSEP’s weekly Friday meetings about internship possibilities for biology students, I was surprised but also immediately interested. At this point I was in the second year of my program, just starting introductory biology classes with only my Summer Bridge internship with the Alaska Department of Fish and Game under my belt as professional experience. Two years later, I am now on my third summer working with polar bear biologist Dr. Karyn Rode at USGS on projects that are genuinely interesting and important to me. What has really struck me about my internship with USGS is that I’ve been able to consistently work on the same project, which makes feel like I’m a part of real science. This is something that I know many of my peers have not been fortunate enough to experience, which makes me so grateful for my time at USGS.

While each summer I’ve gotten to work on numerous tasks and projects, my main project has been running chemistry analyses on polar bear serum to learn if polar bears have been fasting. This is part of a study on the relationship between polar bear foraging behavior and sea ice loss in the arctic. The serum samples for this project came from polar bears captured during the spring in the Chukchi and Southern Beaufort Seas of Alaska, and were collected over the course of three decades.

In theory, spring should be a very successful time for polar bears because their main food source is easier to access, as ringed and bearded seals haul out on the ice to molt and have pups. However, both of Alaska’s subpopulations of polar bears (Chukchi and Southern Beaufort) have experienced rapid changes in their arctic habitats in the form of sea ice decline. and the polar bears’ foraging behaviors (specifically fasting patterns) appear to be changing in response. This study looks to understand the effects that these changes will have on the conditions of polar bears, and hopefully give experts better insight into how to protect them and their habitats.

Since starting this project, I’ve run hundreds of these serum samples, actually completing the last of them this past month. This work, done by myself and others over the course of several years, has contributed to the largest dataset on polar bear fasting to date, spanning from the 1980s to present in two neighboring polar bear subpopulations.

Another really interesting project I’ve gotten to help with this summer has been preparing polar bear samples for contaminant and pathogen analyses as part of a “cumulative effects analysis.” This study aims to look at what individual polar bears have been exposed to via what they’ve been eating.  Contaminants such as chlorinated hydrocarbons, PCBs, and mercury bioaccumulate in the fat of organisms. Because polar bears are at the top of their food chain, it is expected that they accumulate the most of these contaminants. This contaminant exposure can heavily impact a bear’s immune system, making bears more susceptible to pathogens, which can in turn have a large effect on body condition and reproductive success. The goal of this study is to understand the diet history of polar bears and how these diets are changing in response to ecosystem changes, as well as to understand how this is impacting the bears’ condition and success.

I also worked on a genetic relatedness study this summer, which aims to understand how bears begin to use land.  We are especially interested in whether this type of behavior is learned and transmitted through familial relationships, specifically from mother to offspring. My role was assigning parent/offspring or sibling/sibling relationships to a set of bears, which will next be compared to bear location data in order to learn more about habitat use patterns and whether or not closely related bears tend to remain near one another.

Since my time here at USGS I have grown so much not only intellectually and professionally, but also personally. All of the work I’ve gotten to be a part of at USGS has aimed to help polar bears and secure their habitats. I’ve gotten to be part of research on an issue that I was never fully aware of prior to my internship which now means so much to me.  As I’m beginning to decide what my next step will be, I know that even if I don’t become a research biologist, this work I’ve had the opportunity to be a part of will always be extremely valuable and very special to me, and it’s always something my friends think is so cool!