NOAA Teacher at Sea
Jenny Smallwood
Aboard Oscar Dyson
September 4 – 17, 2017
Mission: Juvenile Pollock Survey
Geographic Area of Cruise: Gulf of Alaska
Date: September 8, 2017
Weather Data from the Bridge
Latitude: 55 20.5 N
Longitude: 156 57.7 W
Clear skies
Winds: 12 knots NNW
Temperature: 11.0 degrees Celsius (51.8 degrees Fahrenheit)
Can I borrow a cup of sugar? Just what does a ship do if it starts running low on critical supplies? In our case, the Oscar Dyson met up with the Fairweather on a super foggy morning to swap some medical supplies and other goods that will be needed on the next leg.
Science and Technology Log
You might remember from my first blog post that Alaskan Walleye Pollock is one of the largest fisheries in the world and the largest by volume in the U.S. Because of this, Walleye Pollock is heavily researched and managed. The research cruise I’m on right now is collecting just a small portion of the data that feeds into its management. Being a plankton nerd, I’m interested in the relationship between year 0 Pollock and its zooplankton prey. Year 0 Pollock are the young of the year; fish hatched in Spring 2017.
Year 0 Pollock feed on a variety of zooplankton some of which have greater nutritional value than others. Certain zooplankton, such as Calanus spp and euphausiids, are preferred prey items due to high lipid content, which yield fatter year 0 Pollock.
Other less lipid rich zooplankton prey, such as small copepod species, yield skinny fish. The fat, happy Pollock are more likely to survive the winter, and the scrawny, skinny fish aren’t likely to survive the winter. So why is this important to know? Well, surviving its first winter is one of the biggest hurdles in the Pollock’s life. If it can survive that first winter, it’s likely to grow large enough to be incorporated in the Pollock fishery. So you just want to make sure there are lots of Calanus spp in the water right? Wrong….
Knowing Calanus spp and euphausiids possess higher lipid content is just the tip of the iceberg. It turns out that in colder years they have higher lipid content, and in warmer years they have lower lipid content. So it’s not enough to just know how many Calanus spp and euphausiids are out there. You also need to know what their lipid levels are, which is related to water temperatures. Clearly a lot goes into Pollock management, and this is only a small portion of it.
Personal Log
I have a theory that like minded people tend to seek out similar life experiences. For example, yesterday I was in the bridge getting the scoop on Fairweather meet-up when I met one of the fishermen, Derek. Turns out Derek and I both attended UNC-Wilmington, both graduated in 2003, and both majored in environmental studies. For a while growing up, we lived just a couple of towns over from each other too. What. In. The. World. What are the odds that I run into someone like that? It’s such a small world….or is it?
This is where I get back to the theory that like minded people tend to seek out similar life experiences. There are those people in your life that seem to orbit in the same sphere as you. Maybe it’s shared interests, backgrounds, or experiences, but these are the people that totally “get you.” I feel lucky to have so many of them, from my co-workers at the Virginia Aquarium to the Teacher at Sea folks, in my life right now.
Did You Know?
Did you know Alaska has beautiful sunsets?
