Science for Everyone

Research

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Digging Holes and Identifying Earthworms

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Post by Ben Lemmond, Resident UVM Field Naturalist Masters Student

“Pieces, patterns, processes” is one of the fundamental mantras of the field naturalist program, some of the others being “don’t be a bird plow” and “use the layer cake approach.” About a week ago, one of my committee members by the name of Josef Gorres came to visit my project in situ here on Hurricane. Josef is a soil science professor and earthworm researcher at UVM, and, accordingly, we spent the weekend digging holes and identifying earthworms. Ever since his visit, I’ve had one such process on my mind: how have the soils formed here? And, perhaps more precisely, how has enough soil formed here to support a dense spruce-fir forest, after most of the trees were cleared around the turn of the 20th century?

Not being a soil scientist myself, I can’t give a totally satisfying answer to this question. But here are some of my observations so far.

First of all, I am surprised at how visible the disintegration of granite is. I always thought of granite as some sort of superlatively hard type of rock, but standing on some of the outcrops by the ocean on Hurricane, you can scuff a shoe on any of the rocks and feel the granite flake away; look around, and whole sections of the rock seem to be missing, sliced away in deep cuts by the waves or pulled out horizontally like pieces of some geologic game of Jenga. Standing on granite by the shore gives one the feeling of standing on a giant sugar cube, not on solid rock.

Secondly, the making of soil – that slowest-of-slow process, the inchworm on the ecologic freeway – seems to be happening very much in real time. On the south end of the island, near the old cutting shed, there are a number of rocks that were cut and left behind sometime very close to 1914. You can actually look from one rock to another and see the story of succession and soil development: crust lichens give way to foliose lichens, foliose lichens collect granite fragments and plant debris, eventually enough accumulates to host pincushion mosses, and then finally you start to see vascular plants, who demand the most of their host soils, springing up through it all. As an added bonus, you get a tiny little experiment in island biogeography happening on these rocks, as there is an apparent correlation between the size of the rock and the complexity of the life forms on it.

And, last of all, thanks to Josef, I’ve gotten a glimpse at what lies beneath. There are soils so acidic they expel the iron from the rock and ball it up into knotty concretions. There are weathered chunks of rock, rounded by water from a time when Hurricane Island stood below sea level. Near the cutting shed, there are flakes of granite chipped off by stone workers. Wherever Europeans settled, there are earthworms brought over in ballast soil or garden plants. I’ve got a few collections of soil that I’ll take to his lab now that I’m back in Burlington: I can’t wait to see what else I learn.

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Hurricane-made Passive Drifter Deployed!

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Constructing the drifter in the HIF workshop

Transporting the completed drifter to American Promise

The passive drifter that students from our Marine Biology program made this summer has officially been deployed and is on its way collecting data on currents in the Gulf of Maine! If you want to track its progress click here. Our drifter started its ocean journey with our friends The Rozalia Project aboard their sailing vessel American Promise. They were generous enough to take the drifter out of Hurricane Sound to deploy it in an open water area. The drifter was deployed August 23rd at 43 20.649N, 70 08.923W in 368' of water.

All of this would not have been possible without help from Jim Manning from the National Oceanic and Atmospheric Administration (NOAA). His advice and expertise about all parts of the drifter-building process were incredibly helpful, and if you are interested in building your own passive drifter to contribute to research on currents, and current modeling you can find all of the information you need here.

Hickory the dog looks out at the drifter-- now its path will depend on wind, tide, and currents!

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Researching Down Under​

Post by Bailey Moritz, Scallop Research Intern

The boat is loaded and we’re reading to hop in the water!

Scallop survey dives in and around Muscle Ridge have begun! Cait and I have gotten out on a lobstermans boat several days so far and more days to come. Meeting our captain and his lobster boat at the dock at 7am, we step over bait totes and down the steep metal ramp with our scuba tanks and equipment. Ideally, 4 dives get done in a day. Once we reach the dive site, a 100m transect is laid down with cement blocks and buoys on either end. Fighting against our awkward fins and the rolling of the boat to maintain balance, we hit the water and descend on the transect, down the length of which we will record the number of scallops and crustaceans we see, We’ll also collect the scallops we encounter in collection bags to be brought topside for tissue sample processing and later shell analysis. The bags can get heavy if the site is rich in scallops, so we have to control our buoyancy accordingly.

As it may sound, the survey methods themselves are quite straightforward. Lay out a 100m transect on land and the task is rather simple. But as this has been my first experience with underwater research, I’ve learned that there are definite complications to take into consideration as you descent for a scientific dive.

Jim, the fisherman who took us diving, demonstrates how to shuck a scallop. We’ll keep the adductor muscle for sampling, which is the part people eat. 

Barnacles and seaweed often cover the top of the scallops. This one is a female, indicated by the pink, egg filled gonad.

One of the critical factors for underwater research are the limitations that come with diving. We can only stay down as long as we have sufficient air in our tanks, so the scope of data collected has to fit within that timeframe. As anyone who has gone for a swim in Maine lately can attest to, the water is not warm and since we are diving in wet suits, we eventually get too cold to stay underwater. Tides impact the depth at which each site sits, changing multiple times a day. Some days, the tide and currents are moving strongly and we can get carried off to the side of the transect or just carried right over the top without time to collect any data! The other day, we attempted to do a dive survey, but storms the night before had kicked up a lot of mud and sediment, and the bottom was just too dark and murky to see your hand in front of your face, let alone any scallops. Visibility becomes one of the biggest factors in this type of research.

Another challenge underwater is the ability to write. Fun fact; pencils can write underwater! Because of this helpful perk of the yellow No. 2, we are able to use “writing cylinders” on our wrists, which are a segment of PVC pipe with waterproof data sheets and a pencil taped on, to collect data. Since hand signals can only go so far, they also allow us to write notes to each other if there is a change in the plan or a point of confusion.

Scallop dive surveys will continue into the fall, and we’re crossing our fingers for some sunshine and good visibility going forward!

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Scallops, and Clams, and Mussels, Oh My!

Post by Bailey Moritz, Scallop Research Intern

Mussel jackpot! We’ll put these guys back to grow bigger.

The dock has become my office. Since retrieving the spat bags in late July, I have been whiling away the hours, fog or shine, sorting and measuring the baby scallops in all 35 bags that we collected. Eventually, we will map the data to get a picture of where in Penobscot Bay scallop settlement is higher, which can inform fishery management policy. Even though my scallop count is a whopping 14,000 and counting, I can still say that baby scallops are adorable and surprisingly entertaining. These tiny guys are anywhere from 0.1 to 2 cm in height. By rapidly clapping their shell halves together, they can propel water and thus swim to the surface of the jar I collect them in. Check out Hurricane Islands Instagram for a great video of this phenomenon! My swimming jar of baby scallops has been an excellent show and tell for visitors and students pulling up on the dock. In addition to their cute little performance, juvenile scallop shells have colorful and varied patterns worthy of being called art.

An invasive form of encrusting tunicate forms orange and black mats on the mesh. The little white shapes are clams!

Baby scallops come in a beautiful array of colors and patterns that they’ll eventually lose in adulthood.

Mesh spat bags are not selective. Any larvae floating in the water column can enter the bag and start to grow. While there are upwards of 500 scallops in each bag, there are usually more than 5000 little clams filling the bag as well. Thank goodness I’m not counting clams! The spat bags came from different locations in Penobscot Bay, and you can tell. Each spat bag displays distinct characteristics from the others. One might have lots of healthy juvenile mussels hanging on tight with their byssal threads. Another may have only larger scallops compared to bags with handfuls of practically unseeable small ones. A number of bags contain starfish, thought to be a predator to the scallop, which might be the cause behind a number of empty, crushed shells. I have seen 7 species of beautiful sea slugs, called nudibranchs, and am now well acquainted with tunicates and sea squirts that find the thick blue mesh a perfect point of attachment. I won’t say the number of times I’ve accidentally squirted myself (or others) in the eye trying to peel them off the bags.

Over the course of the past month witnessing the ebb and flow of the tides from my workspace, I have come to appreciate the diverse and unique ecosystem that is a spat bag. What may at first appear to be a mess of muddy shells, shrimp, and slime, actually holds a snapshot of a coastal marine world in an early stage of growth. I still have a few more spat bags to pick through. But with the dock as my office and swimming baby scallops to keep me company, I really can’t complain.

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Desperately Seeking Spat Bags

Some of the bags were completely covered in fast growing seaweed!

Dripping with muddy water and covered with tiny dancing skeleton shrimp, we spent the day searching for and hauling up lines of spat bags. Cait deployed them this past October, so they have been collecting scallop larvae for the past 9 months. A spat bag is constructed of 2 layers of mesh; the outside green layer having very small netting that only larval stage scallops can enter and exit through, and the inside blue layer with larger netting that they can attach and grow on. 5 bags are tied to a line with a cement block on one end and buoys on the other, suspending them at different depths throughout the water column. Soon, we’ll count all the scallop spat in the bags to gain an understanding of how many scallops are entering these areas and how much settlement might be occurring around Muscle Ridge. The bags don’t select for species, so we’re sure to find lots of little clams and mussels as well. 

Keeping the pile of spat bags cold and wet with ocean water

It takes a whole team of eyes to hunt down the right color in the sea of buoys.

Lobstermen generally don’t leave their traps out during the winter and you can see why. The buoys were harder to spot with the colors washed off and some of the bags looked more like we had undertaken seaweed aquaculture! Luckily our fantastic captain, Skip, had a knife handy to clean the outside of the bags as we hauled them up. Strong winter storms can also push the cement blocks across the ocean floor, far away from the GPS point where they were dropped, making it a challenge to find them again. In the end, we recovered 5 of the 12 lines, which luckily included all 3 lines that had the HOBO temperature loggers tied to them! To keep them wet and out of the hot sun, we covered them in burlaps sacks soaked in seawater. After multiple transfers in and out of the water, the spat bags made it on the boat out to Hurricane Island, where we’ll start counting those adorable little scallops.

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