Cold temperatures have arrived and that means it is time to get the second year of kelp sporophytes planted out at the farms! Dr. Lindsay Green-Gavrielidis of the University of Rhode Island has been keeping a watchful eye over the young kelp sporophytes in the URI aquaria. This year, I was around to help with some of the reproductive tissue preparation in the fall. It was quite fun picking out the best pieces of reproductive tissue and getting to cut them out of the kelp blades for Lindsay to process them for eventual spore release. By the time the kelp sporophytes were ready to go in the water, the tubes with line wrapped around them looked like brown fuzzy caterpillars with all the kelps growing attached to the line. For a more detailed narrative of the nursery process check out Dr. Green-Gavrielidis’ post from year one of this blog.
Getting to plant the kelp out on the farms was very cool though at times nerve-wracking. The first task out at the farms was to make sure that the supporting gear was in place. The rope that the kelp is attached to is in the water between mooring balls. It is best to plant on a day without much wind, because with even a small current this rope can be hard to tension close to a straight line between the two mooring balls. Once it was time to plant and the kelp seed line was tied onto the rope, Lindsay and I got into a comfortable pattern of her holding the kelp tube and making sure the seed line fed smoothly onto the rope while I kept tension on the rope. Sometimes the boat would swing about a bit in the current, so the angle on the tensioning was quite a workout. During one of the later planting trips, I wrecked a pair of thick plastic work gloves. The friction between the rope and the gloves was so great that the rope ripped off some pieces of the glove. Once the kelp line was running out, the trick was to hold the rope in place, so that the seed line could be again tied into the rope and sensor rigs for irradiance and temperature data could be left out at the site. The nifty thing about kelp is that once it is in the water the farmers don’t have to do anything other than make sure the gear stays in place. The kelp thrives and grows quickly with the local conditions of light and nutrients.
In other in-the-field news, oyster growth as expected has slowed through the fall and now essentially stopped as oysters go dormant in the cold temps. They live off of resources gathered during the warm summer season. The tagging method we are using with PIT tags in epoxy and a PIT tag reader has performed well for the most part. Some oysters have lost their tags over time. Others died during the warmer months from ambiguous causes or from obvious causes like oyster drills, which are a common challenge for oyster farmers.
Written by: Celeste Venolia