Welcome to the beautiful Akkeshi Marine Station! As you probably have read in previous blogs, our goal this year is to test whether subtidal marine grazers will change their food preference if water temperature increases. If this is the case, we also want to know if this change is more due to alterations in the grazers or in their food, namely macroalgae and seagrasses.
The general idea was to identify a subtidal gastropod, which is abundant in the respective region as a test organism, and to choose 3-5 algae species, which are part of its natural diet. We then planned to acclimate both the grazers and the algae to 3-5 temperatures and conduct a multiple-choice feeding assay by the end of the acclimation phase. In these assays, we combine grazer and algal individuals that were previously acclimated to different temperatures.
The rocky shores near the Akkeshi Marine Station harbour large amounts of the periwinkle Littorina squalida. However, due to their habit of leaving the water frequently, I chose another abundant marine snail, Lacuna decorata, for my experiment. This choice has some merits, but also came with some drawbacks, which I will explain later.
Like all the other teams of this year’s global project, I was also struck by the reality that sometimes deviates from the theory of experimental design and planning. First, I had to deal with my own living in a rural place without a vehicle. To make it more conceivable, I will write about my first encounter with the Akkeshi Marine Station, which was a rather impressive moment.
I arrived in the late night of 20th April and was totally confused when Kochi-san (Professor Massa’s wife) headed her four-wheel drive RV off road into a dark forest, where a steep, narrow stony path appeared under our car. Finally, the car reached a flat ground after some minutes of a heavily shaky journey. I heard sound of waves but still couldn’t see anything. There was a dim light coming out of the darkness behind and suddenly someone turned on the street lamp, so I could finally see the dormitory in front of me.
In the following few days, I explored this isolated marine station and its surrounding step-by-step. The more I knew, the more fascinating it became. There are currently 12 staffs working in the marine station including me, and I am the only one who lives in the dormitory building next to the laboratory. Every morning, they park their cars on the top of the hill, where the normal paved road ends, and walk down 100 meters, following that steep, stony path to the laboratory. The marine station and the dormitory are placed on a small cliff right at the rocky shore, being far away from other parts of Akkeshi town with 5 kilometers of a hilly road and forests in between. This environment thus creates a close and warm atmosphere among our small community, despite some language barrier between us.
In the beginning, being without a local partner seemed to be a scary disadvantage to me. I did not know the place, I did not know the language, and I did not had a car. It wasn’t so pleasant to rely on others even for the most basic things, such as grocery shopping. Fortunately, Minako and Mizuho, the 2 PhD students at the marine station have experiences with several generations of GAME students, also the Japanese GAME participants from the past 2 years are still here for their master’s degree. Takaaki, who joined the GAME project last year, helped me a lot with the set-up in the beginning, as I decided to follow the same structure that has been used by several former GAME participants. We converted shallow plastic tanks covered by Styrofoam into waterbaths, and destined some old lunch boxes with wholes in them as water distributors in a flow-through system.
Since the requirements of my study are different from those of previous GAME experiments, I needed to make adjustments to the set-up. This includes drilling holes on the bottom of the lunchbox, connecting tubes with the boxes, applying and arranging the heaters and pumps to different tanks and making individual containers for the animals.
All those steps above sound simple, but it took me 1 month to make it works as I wished to. Most time was spent on fixing individual tubes and homogenizing the water temperature among the containers within each water bath. Since everyone in the lab is very busy with their own projects and has not much spare energy taking care of me, I usually do treasure hunting first throughout the lab when I needed something. If there was really no way for me to find the right thing, I either took out the old bike from the storage room and went to the hardware store in Akkeshi by myself or I asked someone to buy stuff for me. This situation was surely stressful, especially as I was experienced with neither the lab nor with building up a system to keep marine organisms. However, by forcing myself to contemplate upon an issue first rather than directly asking for help, it turned out that many things could actually be done with limited resources, and thus reduced waste production and money expenses.
By the third week of June, I finally reached the point to start the first pilot study, in which I wanted to identify a reasonable temperature range for the main experiment and get to know the feeding behavior of my little Lacuna. These lovely little fellows are abundant on the sea grass bed along the coast of eastern Hokkaido. There are few papers about their feeding and habitat behaviour, I therefore needed to find out first if the algae chosen are suitable for conducting the main experiment. However, the first pilot didn’t go as smooth as I hoped. The snails were relatively small and thus did not consume much per individual, what caused huge errors when I calculated their consumption rates from measuring the wet weight of Ulva pellets after the snails grazed on them for 24 hours. Nevertheless, I learned about the thermal tolerance of these tough guys: They don’t really care even when the temperature is raised 10 degree Celsius higher than the ambient temperature in their natural environment!
The second pilot study was more straightforward than the first. I wanted to find out what kind of food Lacuna eats. After discussing this issue with professor Massa, four food sources were chosen, namely the green alga Ulva pertusa, the brown alga Fucus distichus, the red alga Chondrus yendoi, and the seagrass Zostera marina. These species are abundant at the rocky shores of Akkeshi and are part of the natural habitat of Lacuna. However, it was not before the end of this pilot study, that I realized how much these fellows dislike the artificial food pellets, although conventionally they are widely accepted as a standardized food source for marine experiments, and all the animals from the other GAME teams of this year love them. At this stage, they were feeding in an obvious manner, and feeding marks became the representation of joy—the more the Lacuna ate, the more relieved I got, as that confirmed the suitability of algae selection for the main experiment.
My target animal, Lacuna decorata, is a marine gastropod that belongs to the family Littorinidae. Their adult size ranges between 5-12 mm, they are relatively abundant, at least during certain seasons, and they are tough. I collected all of the Lacuna individuals for my study at the coast next to the laboratory. As the ocean here is generally cold throughout the year, being soaked in the water won’t be the best idea. I thus needed to wait for the spring tide that comes every two weeks, and then use precious 50 minutes to find those little hidden snails. In early May, this was quite an easy task. Despite the cold water and the blowing winds, Lacuna was active with mating, so the snails climbed up from the dense seagrass bed to the floating kelp blades, waving their tiny tentacles and pairing up happily. All I needed to do was to keep flipping the kelp blades and voila! More than hundred snails were in the buckets within 50 minutes. However, as the weather became warmer and being inside the water was not so painful anymore, the collecting process itself became less cheerful. This was because Lacuna has an annual lifecycle, which means that most of the adult individuals start dying after spawning. The newborn babies were so tiny that one could barely see them with naked eyes, not to mention trying to use them in the feeding assays. By the end of the second pilot study, it became clear that the main experiment was a race against time. As the summer gradually came (although it was still pretty cold for my standards), not only the adult snails were dying on the field, but also all the algae species chosen for the experiment started to degrade. By the end of June, 2 hours of collection only yielded around 90 snail individuals, and even with the help of a dragnet this was all I had for the main experiment. Nevertheless, the main experiment was done by the end of July, and hopefully the data will show some interesting patterns. So far they seem to have a stronger interest in Fucus, regardless of the temperature, but when the temperature is higher, they would give more tries to Ulva.
Despite the fact that 80% of my stay consist of lab work, the other 20% are truly mind refreshing. Hokkaido is a huge island that is about 21% of the size of Germany, with around 5 million residents, which means that large parts of it are rural and it is full of beautiful nature. It was given the name “Hokkaido” only until the year 1869 and officially became a province under Japanese government. Before that, the island was dominated by the indigenous Ainu people, and this causes the island to be very different from the rest of Japan nowadays. Places have special names originated from the Ainu language, also the local festivals possess mixing elements. I was lucky to join several trips with my lab mates and with the participants of summer schools held by the marine station. We also visited the famous Akan national park. All around the island, there are several active volcanos and, as a consequence, many hot springs, each featuring a unique mineral composition. On the road you can see plenty of wild animals passing: the Ezo deers, Ezo foxes and sometimes, if you are lucky (or unlucky) enough, the Ezo brown beers.
It is really a great experience to stay in Akkeshi, especially if you are a nature lover and don’t mind being away from the buzzling city life for months. Here you can definitely focus on the research project, together with a group of amazing people.
I would like to give special thanks to Mizuho, Minako, Takaaki, Mone, Professor Massa, Sudo san and all the kind technicians and people I’ve met during my stay. You helped me not only with the experiment, but also daily life matters. The purpose of me being here was not for the people, but the people are one of the most precious elements during my stay.
Yun-Ting Jang (the one-woman Team Japan)