It’s 5:30 am and we just loaded up the Costa Lab truck with the cages and gear and pulled out of Long Marine Lab. Some heavy lifting early in the morning will sure do the trick to get your blood flowing and wake you up. The cages are not usually needed for most fieldwork days, but today we are off to Año Nuevo Reserve, home to a colony of northern elephant seals, to find two lucky juvenile northern elephant seals to partake in my study. It’s spring time—although it doesn’t feel like it with the 5 layers of clothes I’m wearing—and the breeding season is coming to an end. Most of the mature elephant seals have headed back out to sea for their foraging migration, leaving behind 3-4-week-old weanlings amongst juveniles that have recently returned from sea to molt. We will pick two juveniles to equip with expensive biologgers that will collect the data I’m interested in for my research.
Año Nuevo Reserve, which is also a California State Park, is ideally located 30 minutes north of UC Santa Cruz. For my study, juveniles are picked up at Año Nuevo and dropped off in Monterey (green dashed line) and swim back home to Año Nuevo (blue dashed line) within a few days. This type of field experiment is considered a “translocation study” and it is commonly used to understand how animals behave and interact with their environment. Because elephant seals instinctively return to their home colony to breed and molt, we are able to take advantage of this to study their natural at-sea diving behavior over a few days. That’s right—my research project relies on 1-2-year-olds being able to find their way back home to Año Nuevo from their drop-off location over 60 miles south in Monterey.
Did the two juveniles safely return with the expensive tags? What data was collected and why?
Follow me as I share my experience as a 1st year graduate student conducting my first translocation study with these amazing animals.
First things first: what motivated me to go to graduate school and wake up before the crack of dawn to do science?
My interest in the ocean and its diverse fauna was sparked at a young age at a small coastal town in my native country of Brazil. One curiosity gradually stood out over the years—the amazing physiological adaptations of diving marine mammals.
After completing an undergraduate degree at the University of Miami studying both marine science and biomedical engineering, I realized I wanted to begin a research career and use technology to study the physiology and diving behavior of marine mammals. So, I applied to graduate school where I knew I’d be able to explore my interests, enhance my abilities to conduct quality research, and get on the right path to establish a career in academia.
As a graduate student in the Ecology and Evolutionary Biology Department at UC Santa Cruz, I study how diving marine mammals are adapted to the marine environment, and how they might be affected by anthropogenic disturbances and environmental change. I knew The Costa Lab at UCSC would be the perfect fit because my interests align with the lab’s expertise in using biologging techniques to study the behavioral and physiological ecology of marine mammals. The lab has also been extensively studying the population of northern elephant seals, one of the most extreme divers among pinnipeds and thus an ideal model species for diving physiology, at Año Nuevo Reserve and has all the permits and resources to conduct this research.
Right from the start, I dove into fieldwork. During the breeding and molting seasons, when the colony is full of elephant seals, we drive 30 minutes up the coast to Año Nuevo every morning to conduct resights. Resighting alone already provides us with valuable demographic information about the colony, but with the advent of biologgers (check out this blog for some neat history) we have been able to investigate mysteries about these animals when they go out to sea for months at a time.
Due to 40+ years of resighting efforts, we now know the population at Año Nuevo very well—how old the animals are, whether they were born at Año Nuevo, which individuals reliably come back, and whether they’ve worn our tags before. That is how we choose the adult candidate animals each season on which to deploy our instruments and who will contribute to our science.
I came to The Costa Lab with a broad set of interests in physiological adaptations of diving marine mammals, knowing that I would have a wide array of possibilities to delve into this topic. Picking a research focus as a graduate student is both exciting and overwhelming. Exciting because I have the freedom to investigate questions that fascinate me, but overwhelming because I want to find a specific niche to make significant contributions. It will definitely be challenging, but I am looking forward to the next few years as I continue to gain new fieldwork skills and progress in my research. Keep an eye out for my next blog post to continue following our work at The Costa Lab!
Written by: Arina Favilla, PhD Student, Ecology and Evolutionary Biology, University of California Santa Cruz.