Marine Mammal Ecology Lab

September 2018

REU final thoughts and plans for fall

Wyatt Heimbichner Goebel, undergraduate student

1 September 2018

I have recently returned from my REU studying the kinematics of gelatinous zooplankton. It was one of the best experiences of my life thus far. I learned a ton about what it means to be a scientist from initial observations to developing a research question and on to analyzing results. That experience has given me skills and knowledge that can be applied directly to future research experiences. In addition, my mentor and I have decided to move forward with the project in an attempt to publish a paper. This is very exciting as it will be my first experience publishing a scientific paper. I have nothing but good things to say about my REU experience as I now feel that I am a much better researcher and that I have increased my knowledge of marine biology tenfold.

In looking ahead to the coming quarter at the marine mammal lab, I have started to think more about what topic I might like to focus on for my project. I initially had the idea to look at harbor seal social behavior. This idea came from discovering a few papers that asserted harbor seals don’t form lasting social groups and that they only haul out in large numbers as a predation avoidance strategy (Godsell 1988, da Silva and Terhune 1988). Although I’m not sure how exactly to go about investigating it, I am still interested in looking at whether we see changes in harbor seal social behavior in response to the construction occurring at the Bellingham waterfront. Perhaps the seals form groups more often in response to the disturbance or perhaps it isn’t effecting their propensity to haul out in groups.

 

Another topic that I am interested in investigating is the effect of construction noise on the seals. The inspiration for this topic comes from a seminar I saw while at my REU. The speaker was Dr. Leigh Torres from the Geospatial Ecology of Marine Megafauna Laboratory at Oregon State University. She presented some preliminary data from a project looking at the effect of ocean noise on grey whale cortisol levels. I am interested to see if something similar can be done with the harbor seals in Bellingham Bay. I did some research and found a paper assessing the effect of pile driving sounds on harbor seal hearing published this year (Kastelein et al. 2018). This seems like an active area of research that would be great to jump into. However, this is just an initial idea. I don’t have a clear picture of how I would go about investigating this idea yet. I’m excited to get back to observing seals now that I am back in Bellingham. This school year will surely be an exciting time in the marine mammal ecology lab.

References:

  • da Silva, J., & Terhune, J. M. (1988). Harbour seal grouping as an anti-predator strategy. Animal Behaviour, 36(5), 1309–1316. doi: 10.1016/S0003-3472(88)80199-4
  • Godsell, J. (1988). Herd formation and haul-out behaviour in harbour seals (Phoca vitulina). Journal of Zoology, 215(1), 83–98. doi: 10.1111/j.1469-7998.1988.tb04886.x
  • Kastelein, R. A., Helder-Hoek, L., Kommeren, A., Covi, J., & Gransier, R. (2018). Effect of pile-driving sounds on harbor seal (Phoca vitulina) hearing. The Journal of the Acoustical Society of America, 143(6), 3583–3594. doi: 10.1121/1.5040493

Researching group behavior of harbor seals

Madison McKay, undergraduate student

1 September 2018

As I mentioned in my last blog, I am looking deeper into the interactions between seals and whether or not these interactions affect how they hunt. In order to understand what we are observing in the creek, I first wanted to do some background research to see if I could find anything on the differences between behavior of groups and individuals, as well as more technical information on their hunting mechanisms.

The first article I came across attempted to display all of the information known at the time about harbor seals. This included habitat, general behavior/movement, fighting, breeding, diet etc. The article found that seals typically congregate in herds during summer, spending time in small groups or individually during winter (Scheffer & Slipp, 1944). Because this article is so dated, I cannot be sure if the information is still true, or if it would apply to the seals we observe in the creek.

A more recent article I read researched the effect of tide on seal predation of salmon and forage fish in the San Juan Islands. I found this article interesting because we record tidal data in our observations, and it is important to account for all of the factors that could be affecting hunting success of the seals. In this study, they used seal abundance and success rates to determine if the tide was influencing their distribution, behavior and foraging success. It was found that tidal differences do in fact impact hunting, and fish capture rates are unlikely to be related to group foraging events (Zamon, 2001). The researchers noted that most seals were either hunting alone or in mother-pup pairs. It was also difficult to collect data on seals hunting smaller fish; in this scenario they do not surface to eat (Zamon, 2001). This article gave me some valuable information on the hunting behaviors of seals, the influence of tides, and also made me realize how amazing our study site is. The seals in the creek are hunting salmon, and almost always surface to eat their prey. This makes it very easy for us to record data on their hunting success.

Finally, I found an article detailing the senses seals use to hunt. In this study, seals had different senses blocked out and were tested to see if they could find an object (a propeller-driven submarine). The main goal was to see how much of an impact the whiskers have on the seal’s ability to find its prey. It was found that blind-folded seals can successfully find their prey (the submarine) by solely using their whiskers (Dehndardt et al., 2001). Because they rely so much on using their whiskers to find prey, it leads me to think hunting with other individuals may interfere with these senses.

I am excited to start doing more research on group behavior, and think this information has given me a good place to start! It will be interesting to compare what I have learned to what I observe in the creek.

On another note, this past month I was able to go up to Seward, Alaska to spend time with family and go fishing. While there, I visited the Alaska Sea Life Center and got to learn more about the current research they are conducting. One project that stuck out to me was the Stellar Sea Lion Remote Monitoring Project. Researchers will keep track of the sea lions, identify them, and monitor their behavior. It reminded me of our project, and made me excited to see something similar being used to monitor other marine mammals!


Here is a cute otter I saw in Alaska! Hopefully everyone is having a relaxing end of summer just like this fella. Photo by M. McKay.

References:

  • Dehnhardt, G. et al. 2001. Hydrodynamic trail-following in harbor seals (Phoca vitulina). Science293: 102–104. doi: 10.1126/science.1060514
  • Scheffer, V. B. and Slipp, J. W. 1944. The harbor seal in Washington State. American Midland Naturalist 32: 373. doi: 10.2307/2421307
  • Zamon, J. E. 2001. Seal predation on salmon and forage fish schools as a function of tidal currents in the San Juan Islands, Washington, USA. Fisheries Oceanography 10: 353–366. doi: 10.1046/j.1365-2419.2001.00180.x