Clara Bird is a Masters student in the Geospatial Ecology of Marine Megafauna Lab of Oregon State University where she’s using drone footage to investigate the relationship between the body condition and behaviour of gray whales. Drones have several advantages over boats for studying gray whale behaviour. For example, by being able to capture sub-surface activity, drones can reveal far more behavioural information from each encounter and, flown responsibly, can do so without eliciting the behavioural responses that a close approach by boat would. The drone footage has been collected in Oregon since 2015.
What kind of behaviours has the drone footage revealed and have any behaviours surprised you?
Our drone footage has allowed us to identify several specific foraging behaviors that can’t be seen from a boat which has been really exciting. I hadn’t studied gray whales before starting this project so I’ve really enjoyed seeing all their behaviors, but I think I’ve been most surprised by their surface feeding behaviour. Sometimes they feed just under the surface by swimming on their side and it looks like they’re taking bites of the water, something I’ve taken to calling pacman-ing. I also think I will always be surprised by how wiggly these whale are.
When you were at Duke University, you developed a semi-automated algorithm to count penguins on an Antarctic island, a tool that dramatically reduced the time taken to process drone images and eliminated human error. How will you use algorithms to assist your gray whale research?
At the moment I don’t think I’ll be developing any semi-automated algorithms for this project. But, I have been writing some tools in python to help myself with the analysis part of the project. So far I’ve written a tool to draw the flight path of the drone, and quick tools to process the behaviour data after I’ve gone through the videos.
Many of the gray whales seen off the coast of Oregon are recognisable, allowing you to assign behaviours to known individuals and track those individuals through time. Will you be using this information in your study and, if so, how?
Yes! One of my big questions is asking if we see individualization in the behaviors. Do certain individuals perform specific foraging behaviors or do they all perform all the behaviors? This will be helpful for informing conservation because it’s important to know if we can say that a pattern is present within a population or if is individual-specific.
You’ve hypothesised that there’ll be a circular relationship between the body condition and behaviour of gray whales. So, not only that behaviour will vary by body condition but that body condition will be affected by behaviour. What are the implications of this?
This question has important implications for conservation and monitoring the health of the population. Looking at how body condition and behaviour are related will could help contribute to our understanding of why some whales are so skinny. Also, I think that incorporating behaviour into our assessment of the health of these whales is an important component that hasn’t yet been considered for our whales.