by Anne Beaudreau
There are many measures of success in fieldwork. The first, and most obvious, is whether you catch fish. They can’t just be any fish; they have to be the right fish to meet your study objectives. A second measure of success is whether the crew gets along. Luckily, most everyone I know in the field of fisheries loves to be outdoors. But you never know how personalities and expectations will mesh when everyone is wet and cold. Of course, the most important measure of success is whether everyone stays safe (and staying safe also means protecting the boat!).
Since 2012, the Coastal Fisheries Ecology lab has been studying the ecology of juvenile sablefish. Two weeks ago, before our team left for Sitka to begin a new phase of our sablefish field research, we were facing a lot of unknowns: Would we catch fish? NOAA researchers had caught juvenile sablefish in October during the 1980s and 1990s, but that was a while ago and every year is different. Would the weather hold up? This was fall in Southeast Alaska after all. Wind could be a real threat. Would there be any issues with the rental boat? We were pretty sure that the 22-foot Hewescraft would be just what we needed to get the work done, but hadn’t worked with the company before.
Pre-fieldwork uncertainty can be stressful. But uncertainty brings with it the promise of discovery, of seeing something new even in a place you have visited countless times, of learning something about the system you are studying. So, how did we do? Were we successful? If you read the title of this post, you’ll probably guess the answer: a 5-star week on all counts! Here’s a recap of the highlights, with reflections from the whole crew.
Catching the right fish and learning on the job
We were hoping to catch a range of ages and sizes, to understand whether young sablefish at different life stages store energy differently before they enter the lean winter months. Matt Callahan, the lead MS student on the project, and I had been planning this work for months and were eager to find out if, in fact, we would catch the “right fish.” Within the first moments of fishing we had our answer. As Matt said,
The most memorable aspect for me was the first day, or really the first thirty seconds of fishing. After months of planning and uncertainty as to whether we’d even catch fish, we finally put our hooks in the water and BAM! Our hooks barely hit bottom before getting swarmed with hungry, hungry sablefish.
Joe Krieger, a postdoc and collaborator on the project, was amazed to see the behavior of the fish in the wild. He said,
I’ve been feeding young-of-the-year sablefish in the lab so I had some appreciation for their lustful appetite and piranha-like feeding displays, but that was nothing compared to looking over the boat and seeing a swarm of 20-30 sablefish streaming to the surface in pursuit of my jig. Their voracious appetite and apparent generalist feeding strategy certainly help to explain why these fish are able to grow as quickly as they do.
Justin Priest, a MS student studying Arctic fish ecology, agreed:
The way that the fish were so clustered really surprised me. Fishing 100 feet in either direction yielded almost no fish, but when on top of them, there were a lot down there…how voracious they were really surprised me.
We retrieved the stomach contents of the ravenous sablefish using gastric lavage, a non-lethal technique that involves flushing out the stomach of a sedated fish with a gentle stream of water. I have lavaged thousands of fish, from 30-pound lingcod to baby salmon no longer than my pinky finger. Yet, I am still excited each time to see what ecological clues lie inside the stomach of a fish. Luckily, Matt, who will be doing a lot of gastric lavage over the next couple years, found it fun too:
I learned how to perform gastric lavage, and enjoyed seeing the stomach contents pour into the sieve. It’s like a box of gross fishy chocolates, you never know what you’re going to get.
As with all fieldwork, there were unexpected challenges. One of our goals was to measure the energy content of the main food types being eaten by sablefish in the fall. Sablefish were primarily consuming juvenile herring, amphipods, euphausiids (krill), and jellies. For most prey groups, we were able to salvage intact, minimally digested prey from the stomachs. As Cheryl Barnes (PhD student) noted, “sablefish eat tiny euphausiids,” so we tried to supplement euphausiid samples from stomach contents with field collections of more intact prey. Our attempts to catch euphausiids using light traps was unsuccessful, but we have some ideas about how to improve the process next time.
Camaraderie and teamwork
Science is fun when you’re working with fun people. And this crew sure was fun! In between the serious work of research – navigating to the study site, catching fish, recording data, keeping fish alive – we did a whole lot of laughing and snacking (see below). Rhea Ehresmann, a MS student studying sablefish movement ecology, said it best:
The most memorable aspect of the fieldwork was getting to know everyone better. Fieldwork provides an opportunity to disconnect from phones and email, and focus on the project together. We were able to spend more time in person working and talking together as a team.
As far as safety goes, the owner of the boat rental company had set a low bar as he handed us the keys: “Just don’t sink the boat!” I’m happy to say that not only did we not sink the boat, but we got our crew safely to St. John Baptist Bay and back every day. Yes, we got soaked with rain and sleet, but the wind was kind and I saw more rainbows in the span of one week than I thought possible (outside of Hawaii). Joe summed it up perfectly:
Having just moved to Southeast Alaska I am still awed by the natural beauty of the Inside Passage: snow covered mountains, endless forests, sunlight glistening off the ocean surface, sea otters, bears. I could go on and on. We were extremely fortunate to have several excellent days of weather, which really was the cherry on top of an all-around great trip.
We also did a lot more singing than I expected. Wednesday was Alaska Day, and Matt serenaded us with the Alaska state song on the way to the boat. We topped off the week with karaoke and an impromptu dance party at Ernie’s Saloon, in celebration of Joe’s birthday. A sign of a good week in the field indeed.
Our favorite field snacks
Joe: Definitely the dark chocolate covered dried mango. I probably ate over half of the bag. Dark chocolate and fruit are healthy right?
Rhea: My go-to favorite field snack is cheddar and caramel popcorn mix. It makes a great snack because it satisfies salty and sweet cravings at once!
Cheryl: duplex cookies 🙂
Justin: Of course Grandma Tillie’s. And I’m not even a sweets guy!
Matt: Grandma Tillie’s blueberry donuts with lemon glaze narrowly edged out her pumpkin rolls. Mmm, so good.
Anne: I gotta agree with Matt and Justin!
In a future post, I will talk more about the research itself and why we think sablefish are so interesting. For now, you can find more information about the sablefish studies on our current research page.
All photos in this post are courtesy of the Coastal Fisheries Ecology Lab unless otherwise noted.