Week 4: Through the land of the pyrosomes and home
As we continued southwards on the Coastal Pelagic Species (CPS) Survey and the water temperature increased, the assortment of fish and invertebrates in the hauls changed. Fish species in the catch switched from Pacific mackerel, jack mackerel, and Pacific herring to northern anchovy. However, one species was present in every haul and increased as we moved south, pyrosomes.
Pyrosomes are tunicates. Tunicates make their living by pumping water through their bodies and filtering out plankton. The tunicate body comprises a flexible outer skin (“tunic”) covering a netlike structure (branchial basket) that filters plankton and absorbs oxygen from the water. The body of the tunicate has two openings, one for water to enter and the other for water to exit after being strained through the brachial basket. Many tunicates live attached to rocks, docks or other solid surfaces. However, pyrosomes float freely in the ocean, and instead of single animals, they are colonies of many animals. Pyrosomes are typically found in subtropical waters and were relatively rare off California and Oregon prior to the incursion of warm water off the coast, known as The Blob, in 2014. Since then, numbers have increased, with an especially large bloom off the Oregon Coast in 2017 that resulted in many pyrosomes washed up on beaches.
Pyrosomes look like pink translucent cucumbers with bumps. The colonies are firm, a bit softer than an actual cucumber and very slimy. One end is rounded and closed while the other is open. Water is pumped by the individual animals from the outside to the inside and exits from the open end, providing a weak source of propulsion. Off the Oregon coast, most were small, 2-5” long. As we moved south, the number and size of pyrosomes increased, with typical sizes ranging from 6-12” long off Monterey. Pyrosomes bioluminescence, which is the source of their name. Disappointingly, we did not see any signs of luminescence in individual colonies or in the water. Rather, during sampling, pyrosomes were mostly a slimy nuisance that had to be sifted through to find CPS samples. In hauls with large numbers of pyrosomes, we often found fish that had been stuffed into the open end like some sort of fish sausage.
So are pyrosomes more than just a nuisance to fishers and fisheries biologists? Are they related to the effects of climate change in the ocean? Are they eating plankton that some other species would be eating if no pyrosomes were there? Their role in the coastal ecosystem is not well understood.
When we reached the San Francisco Bay, we suddenly realized that the end of our leg of the survey was rapidly approaching. We were quite busy with large hauls of anchovies and, of course, pyrosomes. As the days counted down, it was that odd mix of eagerness to return home after a long trip and nagging worries that we had not done all the things we intended to do. After the last night of sampling, we thoroughly cleaned the fish lab and prepared things for the next leg. The last full day aboard found the whole ship in a very good mood, with everyone looking forward to returning home. Early on the last morning, we sailed into San Diego harbor, past small boats headed out for a day of sightseeing or fishing. We spent a short time spinning circles off downtown San Diego to check the compass and then off to the pier. The ship was docked quickly and efficiently and almost before I knew it, I was walking down the pier dragging my wheelie bag behind me. I paused to look back at the ship and take a couple photos. It had been some hard work but all in all a very good experience. I got to be a working field biologist again, worked with great people, and got to see some cool fish and invertebrates.
Week 3: The certainty of the unexpected
Now that we have been working together for a couple weeks, processing samples is going quite smoothly. Sorting the sample, identifying species, weighing, collecting and measuring otoliths have become routine, as have the protocols for recording data. It is important that these things remain constant (with a few well considered and recorded modifications here and there) because when you are working in the field almost nothing else is.
It is almost certain that something unexpected will happen during a field expedition. Bad weather, animals that are not where you expected them to be, and equipment failures are all very likely. When you do something as complex as sending a ship out to sea, the uncertainties and unexpected multiply even more. As I said in my last blog, the protocols are the skeleton of the study. This skeleton also needs a few joints so it can bend in response to changing conditions.
The most important thing (in terms of the study) is to be able to remain consistent so that you continue to gather valid data. Studies are designed with contingencies in mind, to adapt to the unexpected. Specific data are usually prioritized, so if for some reason there is not enough time to collect all the data you had planned on, you will still be able to collect enough of the most important data to fulfill the aims of the study.
It is not all negative though, as plans are also made for unexpected opportunities, for example, if time permits additional data may be gathered to support other studies. Since field time (especially ship time) is so expensive, there are frequent requests to collect information for other studies.
When you are in the field, there are also concerns beyond just the science. Since the whole group is together 24 hours per day, in potentially hazardous circumstances, the safety and health of the scientists is a primary consideration. Our trawl supervisor not only oversees the collection and recording of data, but takes an active interest in our health and morale.
Even with all the uncertainties of shipboard life, one of the constants on the ship is the food. On the Reuben Lasker the food is good, with variety as well as quality. The ship’s mess is also the social center of the ship, though this has been a bit hampered by social distancing considerations, due to COVID19. People come together for meals, or on a break for a snack and a bit of socializing. The mess is a critical part of the shipboard community, allowing people to interact in a non-work situation. This is very important when it is impossible to get more than 200 feet from your duty station without resorting to swimming.
This week, we began surveying just south of Newport, Oregon. The Coastal Pelagic Species (CPS) Survey is conducted along transects that run from as close to shore as safely navigable to 30-50 miles offshore . Along these lines, researchers collect data with echosounders that detect fish schools, a Continuous Underway Fish Egg Sampler (CUFES) that samples fish eggs and larvae, and a trawl that captures fish.
During the day, the echosounders aboard Lasker are used to detect concentrations of fish and other organisms as the ship moves along the transects. At the same time, the CUFES continuously collects water samples that are examined for larval fish and fish eggs that are species of interest (Pacific and jack mackerel, herring, sardine and anchovy). The echosounder and CUFES data are used to determine where to trawl later that night, when the fish move closer to the surface.
We pulled in our first trawl around 2 AM, the morning after leaving Newport. It was a small catch that served as a good training opportunity for me and the three other new members of the sampling crew. We reviewed methods of weighing and measuring fish and collecting otoliths and other tissue samples. Perhaps more importantly, we learned the protocols for collecting and recording data, including what data to collect, how to record it, and the general workflow of sampling. These protocols allow us to collect a lot of data, often multiple items per individual fish, and turn it into usable information in a database. Protocols are the skeleton of any study that the rest of the study is built upon.
In the following days, the catches have grown in size and variety. The sampling protocols are becoming routine, though it is always exciting to see just what will turn up in the net with each haul. There are pictures posted on one wall of the lab to aid in identifying the fish. It has become somewhat like a Pokémon hunt with people looking at the pictures as the net is pulled in. We speculate as to which species will appear or hope an interesting looking species will show up in the catch.
The ship operates 24 hours a day, with someone always awake while others sleep. I work the night shift from 7PM to 7AM. Those on the night shift have to endure a few sleepy shifts until their bodies make the transition. This also leads to the interesting situation of how to greet someone after first waking. We tend to default to “good morning,” even if it’s 12 PM or 4 PM or 1 AM. It seems a bit weird, but saying “good afternoon” just after waking up seems weirder. I think I will stick with “good morning.”
Another thing you have to get used to is that the world moves. It moves to varying degrees and sometimes-unexpected directions. Of course, this is due to the motion of the ship on the waves, but when the ship moves, the floor moves, the tables move, and everything on the table moves (often onto the floor). Another well-known result of this movement is seasickness. Sea-going staff not only have to deal with the fact that the world is no longer stable, but also queasiness and a dull headache, which is exhausting. Drugs can help (as long as you remember to take them) or you can try toughing it out for a few miserable days while your body adjusts.
For the first 17 years of my career I was a typical field biologist, catching and handling fish, collecting data, falling in the river, etc. Then I worked for NOAA for the next 20 years where I use a computer to help preserve and protect fish in support of the Endangered Species Act. This summer, I had the opportunity to join the Coastal Pelagic Species (CPS) Survey, conducted by NOAA’s Southwest Fisheries Science Centeronce, and once again be a field biologist. The job, collecting data from trawl samples, is similar to my first professional biology job as an observer aboard Japanese vessels, off Alaska, 37 years ago.
The CPS Survey is conducted aboard the NOAA Ship Reuben Lasker off the west coasts of Vancouver Island, Canada, the USA, and Baja California, Mexico. The survey collects data on CPS population structure and reproductive status, and assesses the distributions and abundances of Pacific Herring, Jack Mackerel, Pacific Mackerel, Pacific Sardine, and Northern Anchovy. Sophisticated echosounders aboard Lasker are used to detect CPS schools, which are then sampled at night (when these species come near the surface) with a surface trawl. My job is to collect data from the fish and other organisms captured in these trawls.
Arrival and Departure
Since the survey is being conducted during the COVID-19 Pandemic, strict measures are in place to prevent outbreaks aboard the ship. Everyone quarantined for 7 days and received two COVID-19 tests before boarding the ship. All participants also wear masks aboard the ship.
My wife, also quarantined for 7 days, drove me to the ship at dock in Newport, Oregon. We said our goodbyes and I boarded the ship. I was shown to my room that I share with a member of the crew. The crew of Lasker includes technical experts who operate the ship and its systems, and NOAA Corps officers who drive the ship and help facilitate the operations. Different science teams join the ship, depending on the mission. The crew use their skills to ensure that the surveys are successful. They also graciously welcomed us to their shipboard community.
After boarding the ship we went through emergency drills to learn what to do in case of fire, man overboard, or the need to abandon the ship. These drills included practice putting on our survival suits, thick neoprene hooded overalls that protect from the cold water. This was much easier when I did it 37 years ago.
On departure from Newport, after the Commanding Officer determined that conditions were right, the ship performed a rather neat maneuver by backing away from the dock and swinging the bow around to face the channel. Then we sailed out under the Yaquina Bay Bridge, past the jetties, and onto the Pacific Ocean. There was a gentle swell and I made the pleasant discovery that I still don’t get seasick.