Interview-Hannah Rosen & Humboldt Squid Communication

Humboldt squid & National Geographic crittercam width=
Crittercam being put on Humboldt Squid photo by:Joel Hollander

On April 18, 2015 I attended MARINE’s (Monterey Area Research Institutions’ Network for Education) Ocean Colloquium. There, among many interesting speakers, I heard Hannah Rosen speak about her research on Humboldt Squid communication at Hopkins Marine Station, Stanford University. I was fascinated and I later asked if I could interview her for my blog. The following interview was conducted by e-mail:
1. Tell me a little about yourself and how you came to be at Hopkins Marine Station.
Hannah Rosen (HR) : I grew up in Pennsylvania, but when I was 11 I went to the Monterey Bay Aquarium with my family. I thought it was pretty much the most amazing place I’d ever been in my life, but never imagined I would someday be working right next door. I went to college at Bucknell University and studied animal behavior. I became fascinated with cephalopods and how smart they are. So I decided to go to graduate school and do research on cephalopod behavior. That’s how I found Dr. Gilly at HMS and decided to do research on squid chromatophores and their use in Humboldt Squid.

2. How did you become interested in studying squid?
HR: I first became interested in octopus after reading about their incredible ability to learn and even play. However, when I did more reading I realized that while there was a lot of research done on octopus and cuttlefish, there almost none done on squid because of how difficult they are to study. I guess I sort of saw this as a challenge and that made me want to be the one to work on this research.

3. How do squid communicate?
HR: Squid communicate mostly through body patterns on their skin. Different species have different colors of the expandable pigments sacs called chromatophores, which they can use like pixels on a screen to create different patterns. They often use these patterns in concert with different body and arm positions, and with light reflecting cells in their skin called iridophores.

4. Why did you study Humboldt squid instead of other cephalopods or squids?
HR: I was interested in Humboldt squid partly because of the interesting dynamic they have within their schools. They are always found in groups, but we don’t know if these groups are static or if members come and go. There is some evidence they hunt together, but they are also very cannibalistic. All these complexities made me think they must have a way to communicate with each other to maintain whatever sort of order that seems to exist. They are also large enough to strap video cameras onto, which makes it a little easier to study them than some other squid.

5. How did you get camera footage of Humboldt squid displaying?
HR: We got that footage using National Geographic’s Crittercam, an animal-borne video package that we put on squid that were caught using a squid jig and hand line. The squid were able to swim freely with the camera, which automatically detached after a few hours and floated to the surface, where we were able to recover it and look at the footage.

6. What do you hope to learn (i.e. what your dissertation is about)?
HR: I’m hoping to learn something about how Humboldt squid use their chromatophores, both for communication and camouflage. I am also comparing some of the anatomy of the chromatophores in Humboldt squid to that in California market squid to see if some of the differences in how they use their chromatophores translate into physical differences as well.

7. Have you come across any interesting facts about squid during your studies?
HR: I have learned lots of interesting facts about squid! Some things I have learned that aren’t about my particular research is that squid have blue blood instead of red because they use copper instead of iron to transport oxygen. Also, the have three, one chambered hearts instead of one, many chambered heart.