Science for Everyone

Sea Farm Diaries

Guest blog post by Research Technician Bailey Moritz

Make way for the next cohort of little bivalves!

Make way for the next cohort of little bivalves!

What went in last fall as the size of my fingertip now fills the palm of my hand. With an average growth rate of 0.07mm per day, our baby scallops spent the past year slowly filling up the bottom cages they were placed in. The added size means, just like for my brother and I growing up, that more personal space is needed. We have been keeping our density around 30% and the scallops are now spread throughout 4 bottom cages and 2 lantern nets. We even had a student from Georgetown join our research team for the day and help us with the time-consuming task of taking monthly growth measurements and transferring them to new, more spacious cages. The help was so appreciated! Everyone should come out and take a look for themselves! They seem to be at their peak teenage phase and very active. There is nothing like the joy on someone’s face as they watch a scallop swim for the first time or hold it in their hand while it utilizes its powerful adductor muscle to clap rapidly.

Our second year class keeps on growin'!

Our second year class keeps on growin'!

Our charismatic tiny-fauna will undergo monthly cleanings of the mesh and cage structures, as algae and barnacles grow prolifically during the warmer months. We are really starting to feel like farmers! Especially taking into consideration all the new spat we’ve collected this year, our sea farm and the gear required to make it operational are growing in step with the scallops. Our goal is to ear hang them in the fall once they’ve grown a little larger! Stay tuned.

Tracking the growth rates of tagged scallops

Tracking the growth rates of tagged scallops

This weekend even marked an exciting field trip for a lucky handful of little scallops. Hurricane Island hosted a booth at the Chebeague Aquaculture Festival, giving visitors a chance to look a farmed scallop in the eyes and learn about our goals of research and education through on-island aquaculture. We were joined by an excellent array of speakers, growers, cooks, entrepreneurs, and enthusiastic members of the public! And while those coast-traversing scallops are safely back in their cages now, I think they may miss the taste of warm, growth-conducive water they were briefly given.

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Aliens in the Ice Pond: What Macroinvertebrates Can Tell Us About Our Freshwater Environments

Guest blog post by Science Educator Isabelle Holt

Students sort and identify their net contents using field guides and macro-lenses so they could gather count data for various freshwater macroinvertebrate families.

Students sort and identify their net contents using field guides and macro-lenses so they could gather count data for various freshwater macroinvertebrate families.

The word ecology comes from the Greek words oikos meaning “the family household” and logy meaning “study of.” This past week High School Island Ecology (HSIE) got to explore the world of freshwater macroinvertebrates.

Our ambitious high school students studied the households of our freshwater macroinvebrate communities by sampling in both the Ice Pond and one of the old foundation ponds and compared what they found in each.

Invertebrates are extremely important for all ecosystems and make up 96% of animal species. The freshwater macroinvertebrates, defined as spineless animals that can be seen with the naked eye, on Hurricane are responsible for the breakdown and cycling of nutrients within their ponds similarly to the ways in which earthworms allow for the cycling of nutrients in soil. The species we were studying feed on autochthonous detritus, decaying organic matter that has come from flowering plants, mosses, or algae and is typically high in its cellulous content.

Dragonfly larvae will molt between 5 and 14 times before it is ready to emerge as an adult dragonfly (Image from Shropshire Dragonflies)

Dragonfly larvae will molt between 5 and 14 times before it is ready to emerge as an adult dragonfly (Image from Shropshire Dragonflies)

Many freshwater invertebrates act as indicator species of habitat health allowing for the process of biomonitoring. Dragonfly nymphs, for example are very sensitive to pollutants and their presence in a freshwater system indicates that that body of water is relatively clean and free of contaminates. Don’t let the adult dragonfly’s beauty bewitch you; they are fearsome predators who, in their larval form, look like the aliens of horror movie fame. Dragonfly larvae have extendable jaws called labium that they thrust out towards their prey. Equipped with sharp bristles and pincers, once a prey item is in the grasp of a dragonfly nymph it has little hope. These nymphs have even been known to hunt and capture freshwater fish 10x larger than they are. Upon careful study students noted that the most prevalent family of dragonfly in the Ice Pond were the Libellulidae or Skimmer dragonflies. One student even remarked that the nymphs he was finding appeared to be the inspiration behind Predator, the 1987 science fiction action horror film. Who says science can’t be cool?!  

Fingernail clams are so small they are easy to misidentify as pieces of sediment, however, our observant HSIE students were able to sort through quite a few. (Image from the Natural Environment Research Council)

Fingernail clams are so small they are easy to misidentify as pieces of sediment, however, our observant HSIE students were able to sort through quite a few. (Image from the Natural Environment Research Council)

Closely related to their marine bivalve cousins, the scallops, the freshwater environments on Hurricane are rife with Sphaeriidae otherwise known as fingernail or pea clams. The HSIE students pulled dozens of these tiny bivalves up in their nets from the soft substrate of the ice pond. When sorting through the muck in our nets the fingernail clams looked like little pearls that had burrowed into the surrounding leaf litter. Fingernail clams have a lifespan of 1-3 years but can reach maturity as rapidly as at one month old. One of the reason fingernail clams are so prevalent in freshwater environments is that they can burrow up to 25 cm into soft sediment and therefore are able to avoid desiccation (drying out) for several months at a time.

Anybody home? A student holds a caddisfly larva case who's shy inhabitant hides inside its self constructed home.

Anybody home? A student holds a caddisfly larva case who's shy inhabitant hides inside its self constructed home.

The Humpless Case Maker Caddisflies (Brachycentridae) construct four sided tapering cases made of thinly stacked spruce needles gathered from the environment around them and cemented together with their own spit. These freshwater engineers use whatever is in the environment around them to construct a protective shell and feed by clinging to decaying logs in their environment and filtering small particles of organic matter from the surrounding water. Intriguingly we found more caddisfly larvae in the foundation pond than we did in the Ice Pond. Determining what factors lead to this difference in distribution could be a potentially fruitful area for inquiry by future program participants!  

HSIE returned to the Ice Pond later in the week for the raft challenge and as students constructed and tested their rafts they discussed the creatures they now knew lived beneath its murky waters. Their splashes and kicks in the pond, as they moved their rafts across, allowed these young ecologists to become part of the Ice Pond ecosystem by aerating the water, which in turn increased its dissolved oxygen content allowing the pond to hopefully support a greater diversity and abundance of macroinvertebrates. 

 

 

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Aquaculture from Maine to Madagascar

Guest blog post by Research Technician Bailey Moritz

Baby sea cucumbers ready to grow!

Baby sea cucumbers ready to grow!

Building new sea cucumber pens in the tidal flats

Building new sea cucumber pens in the tidal flats

This spring, before returning to Hurricane, I spent 3 months on a much larger island- Madagascar, that is- as an Aquaculture Intern with Reef Doctor, an organization working on many fronts to address extreme poverty and rapidly dwindling fisheries in villages along the southwestern coast of the African country. The Vezo, whose name means “people of the sea”, rely almost entirely on fishing everything from octopus to parrotfish to sea turtles to make a living and provide food for their household. But as population increases, extra pressure on an already overfished reef system risks leaving people without a source of income. Boats already come in empty, and many have resorted to dragging mosquito nets along the beach, which catch even the smallest juvenile fish. While damage to the ecosystem and marine populations are grim, you cannot simply tell people to stop fishing. Instead, Reef Doctor has set up community run seaweed and sea cucumber aquaculture farms in villages all around the Bay to provide an alternative livelihood that is sustainable both for the ocean and the people depending on it. 

Cleaning a seaweed line free of sediment

Cleaning a seaweed line free of sediment

Villagers drying their harvest on mesh tables (Image courtesy of ReefDoctor)

Villagers drying their harvest on mesh tables (Image courtesy of ReefDoctor)

A globally prevalent seaweed for carrageenan extraction, Kappaphycus alvarezii, is grown on longlines that create habitat for small fish and squid. We rowed out to the farms and assisted with almost daily cleaning of sediment build up that would inhibit growth and checked for damaging invasive epiphytic algae. Ranging from bright green to brown while growing, it dries into a beautiful purple color and is bagged and sold by the kilo to a local processor. The sea cucumbers, called “sand fish”, are farmed in near shore plastic mesh pens. It takes about a year to raise them to market size at which time they are salted and shipped to Asian buyers. Families participating in the sea cucumber program have seen an average increase of 2.53 USD/day of income. I got to help build and stock pens for 20 new farmers since the program has shown so much success. The great thing about sea cucumbers is, just like shellfish, they broadcast spawn, meaning they release their eggs into the ocean and can actually contribute to wild population numbers. I was very impressed with how well both forms of aquaculture were integrated into the local villages and the benefits already accrued after just 3 years of operating!

Wooden canoes called "pirogues" traditionally used for everyday fishing

Wooden canoes called "pirogues" traditionally used for everyday fishing

For me, the parallels to aquaculture in Maine and the role it serves were evident. While sturdy mooring buoys replace the recycled plastic water bottles of Mada, seaweed farming has been bringing a viable source of alternative income to Maine’s fishermen who already have much of the gear and on-the-water knowledge needed to be successful. While waters warm in the Gulf of Maine and threaten lobster catches, coastal communities here need something they can turn to or fall back on in case the wild-caught fishery they work in crashes. Right now, both Maine and Madagascar farms are being driven by community members who are excited about the potential it holds and recognize the need for a livelihood that helps to improve the ecosystem rather than only extract from it. And in both communities, there is an important role for researchers to play in carrying out experiments with the goal of optimizing growth under local conditions and training farmers on the best methods to utilize for success. While never a silver bullet, my time in Madagascar taught me that aquaculture can and actively is addressing environmental and social problems in communities all across the globe.

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Scallops out of Hurricane

Guest blog post by Research Assistant Jessie Batchelder

As an Environmental Studies major at Colby College, my recent alma matter, seniors are not required to complete a honors thesis in order to graduate. Up until the summer before my senior year, I had no intention of voluntarily undertaking such a daunting task - but that was before I spent a summer on Hurricane Island as the Research Intern working on the Maine Midcoast Collaborative Scallop Project. Throughout last summer, I become involved in all aspects of the research project including data collection, processing, and educating students and visitors about our research. With Cait’s encouragement, and the help of my advisor at Colby, I decided to tackle a small piece of this project as my senior honors thesis.           

Placopecten magellanicus

Placopecten magellanicus

My thesis focused specifically on Placopecten magellanicus “sea scallop” larval dynamics inside and outside the Lower Muscle Ridge closure area. Through my research, I aimed to answer the questions: has larval abundance changed over the three-year closure period and does it vary inside the closure area as compared to adjacent fished areas? The data I used to answer these questions came directly from the spat bags we deploy in the Muscle Ridge area as a metric to gauge larval abundance. Much of my summer last year was spent counting and measuring scallops from the spat bags, and it was exciting to take the next step in the research process by analyzing the data I had spent so much time collecting. 

Completing my thesis was not easy work, and there were definitely times of frustration, but those were outweighed by the numerous positive moments and opportunities that came as a result of my thesis. As part of my work to understand current patterns in the Muscle Ridge Channel to determine likely directions of larval transport I interviewed scallop and lobster fishers from the Midcoast area about their perceptions of prevailing current patterns. Talking to the fishers and hearing their perspectives added a separate aspect to my project and exposed me to the world of social science research.

In April, I had the opportunity to present at the International Pectinid Workshop. This is an annual, international conference on all things regarding scallops. This year, it happened to take place in Portland, Maine, which made it easy for me to attend and present. IPW was the first scientific conference I had attended, and it was an incredible experience to hear from scientists across the world present their research on topics including fishery closures, gear modifications, management plans, scallop aquaculture, diseases and much more. Being at the conference also allowed me to interact and talk with senior researchers and graduate students which gave me a window into the many opportunities that are available should my interests remain within the scallop world.

Presenting my thesis at the Colby Liberal Arts Symposium (CLAS)

Presenting my thesis at the Colby Liberal Arts Symposium (CLAS)

While the thesis experience as a whole was filled with challenges and rewards, the most fulfilling part of my thesis, (besides printing the final draft!) was presenting my work at the Colby Liberal Arts Symposium (CLAS), an annual event at the end of the spring semester when classes are cancelled and the entire day is dedicated to the research students from all years, majors, and disciplines have conducted during the past year. During the session devoted to Environmental Studies thesis presentations, I was able to talk about my work in front of peers, professors, roommates, friends, and family. This presentation allowed me to share my academic work outside of the research setting and communicate my research to friends who previously, only thought about scallops under the category of delicious seafood. CLAS is always a wonderful day filled with presentations, poster sessions, speech contests, music performances and art shows, and it was extremely rewarding to present my thesis and share my work with the greater Colby community.

Returning to Hurricane Island this summer as the Research Assistant has allowed me to continue working on the both the Midcoast Maine Collaborative Scallop Project as well as adding another year of data to my analysis. I’m excited to be back for a second summer to continue this work, be a part of the Hurricane community and enjoy all the benefits that stem from living on a beautiful island in Penobscot Bay!

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Phytoplankton Monitoring

Guest post by Research Technician Bailey Moritz

Taking our first phytoplankton sample of the season at our aquaculture site

As waters begin to warm (although it may not feel that way yet!) and nutrients become more abundant, phytoplankton are beginning to bloom off our Maine shores. Seen under the microscope, these tiny algae that make up the base of the ocean food chain form a beautiful kaleidoscope of varied shapes. Some take on the appearance of beaded necklaces or tiny leaves, while others call food to mind with their turnip or pizza slice like forms. However, a number of species can produce toxins that, when consumed by humans eating filter-feeding shellfish, prove quite harmful. “Red tide” as it is commonly called when concentrations are high enough to change the surface water color, builds up in the mussels or clams that feed on it for several weeks. If eaten by someone, the built-up toxin can cause paralytic, diuretic, or amnesic shellfish poisoning (PSP, DSP, or ASP), depending on the phytoplankton species present.

Target species (yellow) to keep an eye out for

The Department of Marine Resources (DMR) regularly tests sites up and down the coast to make sure that an area with a harmful algal bloom will be closed to shellfish harvesting in time to minimize health risks. They rely on volunteer monitoring efforts to make this a success, and we got certified as official phyto-samplers last week. Out on Hurricane, we are sampling weekly at our aquaculture site to report back to DMRs public health branch on the presence of any of these potentially harmful species. If the water is consistently clear of harmful algal blooms over time, we may eventually be able to consume the scallops that we grow here.

An array of different species, including thin chains of Pseudo-nitzschia

Our first sample this week had plenty to look at and I found it so rewarding and fun to learn the species identification. There was a surprising amount of Pseudo-nitzschia which can lead to ASP, although the toxin is not always produced. That will be something to keep an eye on and we sent a report in to DMR. Monitoring coastal waters for changes in phytoplankton populations is critical for protecting those of us who enjoy eating shellfish, the people who grow or harvest them, and to stay vigilant for new species that are moving northward due to climate change.

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