NOAA Teacher at Sea
Jenna Cloninger
Aboard Bell M. Shimada
June 11 – June 26, 2025
Mission: Integrated West Coast Pelagics Survey (Leg 1)
Geographic Area of Cruise: Pacific Ocean, California Coast
Today’s Date: June 15, 2025
Track the Ship: Bell M. Shimada
Weather Data Snapshot: 12:23pm, Pacific Daylight Time
Currently, the air temperature is 65°F (18°C) with a wind speed of 10 knots and a wave height of 5 feet. I was finally able to witness a sunrise this morning during my working hours, thanks to clear skies, and I am staying up a little bit past my “bedtime” to enjoy today’s sunshine.
Science and Technology Log
Trawling operations are in full swing here on the ship! Please enjoy this image of me in front of our two trawling nets, which we pull behind the boat at different depths to target different species of fish.
In these first few days, we are seeing many anchovy! I have quickly become an expert at identifying the differences between anchovy and other fishes that may be brought up with our net. In addition to fish species, we see quite a few small squid and some other invertebrates known as pyrosomes in our net. (See the Did You Know? section below for more information.)
After sorting our catch, we measure and weigh a certain number of the target species (sardine, anchovy, and mackerel) to collect data that helps us characterize their species and size distributions. In addition, some specimens are selected for dissection, where we determine the fish’s sex, reproductive stage, and health; collect tissue samples for genetic analysis; and extract otoliths for estimating age.(For more about otoliths, which are also known as ear stones or ear bones, click here.) This information helps scientists monitor fish health through their life history stages. It’s not possible to catch every fish in the ocean, so scientists study a smaller representative group instead, like we are doing aboard NOAA Ship Bell M. Shimada. This age data, along with other information like length, weight, and sex, is used to create computer-generated models of the fish population. When combined with acoustic data, these models help estimate how many fish are in the wild and predict what might happen if people keep fishing.
In the picture above, you can see that I am using a special tool called an Ichthystick to digitally measure the length of each fish in a specific subset from our catch. I have discovered that, although I do not normally consider myself squeamish when it comes to science, I am not a fan of dissecting fish for otoliths. Instead, I do a lot of the measuring and weighing of the fish, as well as additional tasks to support my teammates while they work on extracting otoliths.
In addition to trawling for fish, NOAA Ship Bell M. Shimada has a special piece of technology known as a CTD. A CTD is a scientific instrument used in marine science to study the properties of seawater. CTD stands for Conductivity, Temperature, and Depth. These three measurements help scientists understand what the ocean is like at different levels. The CTD device is usually attached to a metal frame and lowered into the ocean from a research ship. As it goes down, it collects data about the water’s temperature, how salty it is (measured by conductivity), and how deep it is. This information helps scientists learn about ocean currents, climate, and marine life. CTDs can also carry bottles that collect water samples from specific depths. Scientists use these samples to test for oxygen, nutrients, or tiny organisms. CTD data is very important for studying how the ocean changes over time. (I have not yet seen the CTD in action, but I pass by it every day on the side deck and am hoping that it will be deployed sometime soon during my working hours.)
Personal Log
Adjusting to life at sea is an ongoing process. I experienced a bit of seasickness yesterday right after lunch, but I was able to go to my stateroom at noon (which is the end of my night shift) and sleep it off until my next shift began at midnight. As a person who traditionally struggles with sleep, I am so exhausted after each shift that I am sleeping much better on the ship than I do at home, which I did not expect! In addition, I am eating much better on the ship than I do at home, thanks to our amazing Chief Steward who has been cooking fabulous meals for us. I have learned that mealtimes are very important on the ship, because sitting with your colleagues while enjoying good food is a boost for team morale and helps everyone stay energized.
Did You Know?
A lot of different animals can become caught in a trawling net while fishing, but pyrosomes are some of the most common animals we see during night trawls (aside from our target species of anchovy, mackerel, and sardine). What are pyrosomes? NOAA’s website tells us that pyrosomes are pelagic tunicates, which are part of the phylum Chordata. In other words, pyrosomes are tough, bumpy, gelatinous tube-like animals that gather in large clusters at the ocean’s surface. Like many jelly-like animals in the ocean, we still don’t know a lot about pyrosomes and how they live. This makes it hard to understand how they might be affecting ocean ecosystems. For example, pyrosomes can grow quickly and filter large amounts of water, which could have a big effect on phytoplankton blooms. Before this experience, I had never even heard of a pyrosome, and now, I feel like I am part of a pyrosome party every night!
Good food is VERY important on remote sites / ships – Bad food and moral goes into the dumper and everyone is unhappy – been there ate that