You may know that Friends of Casco Bay’s Continuous Monitoring Station—AKA our “Cage of Science”—gives us vital data about the health of the Bay. But did you also know that observations of what sea life is growing on and hanging out in the station also give us important information about conditions of our waters? In this video, Research Associate Mike Doan shows us some of the sea critters that visited the Cage of Science in August.
We see water itself as fundamental habitat. When water quality deteriorates, eelgrass, plankton, clams, and other marine creatures suffer. Thanks to our 25-year data set on water quality in Casco Bay, we now have a better overall understanding of the health of the Bay. We understand when and which areas of the Bay are likely to exhibit challenged water quality conditions.
Armed with this baseline data, we can now begin to address the question How is the Bay changing?—thus, the establishment last year of our first automated Continuous Monitoring Station. We will also continue to monitor selected sites at the surface, to supplement the historical data set compiled by our Citizen Stewards Program. And, we will look more intensively, using surface-to-bottom transects, at those regions of the Bay which present challenged conditions. New data and observations may help us begin to understand how climate change, excess nitrogen, and the changing chemistry of Casco Bay may be impacting the ocean food web.
Our Nabbing Nitrogen event in 2016 signaled to us that there is a huge reservoir of goodwill from people who want to help protect the health of the Bay and are willing to do that in short bursts of data collection efforts. We foresee new volunteer opportunities in this type of data collection, as well as in expanding other community service projects, such as coastal clean-ups, storm drain stenciling efforts, and issue-education events to inspire Champions for the Bay.
Citizen Steward volunteers will continue to be key to our organization as they help us move into this next phase of work to improve and protect the environmental health of Casco Bay. Casco Bay belongs to all of us, and this Bay is fortunate to have so many Friends.
Climate researchers have found that the ocean absorbs about 25% to 30% of the carbon dioxide released into the atmosphere from smokestacks and tailpipes. When this excess carbon dioxide mixes with water, it can make the water more acidic. This is called ocean acidification.
More excess carbon dioxide can end up in coastal waters as a result of nitrogen pollution from fertilizers, stormwater runoff, and sewage. This nitrogen overdose stimulates a population explosion of tiny plants called phytoplankton. When these plants die and decay, bacteria consume oxygen and release carbon dioxide in bays and coves. This creates even more acidic conditions for coastal critters. This is called coastal acidification.
Coastal acidification is one more stressor for shellfish species already challenged by other impacts, such as predation by milky ribbon worms and gluttonous green crabs that flourish in warming waters. Red tides and other harmful algal blooms, exacerbated by nitrogen runoff, may close clam flats to shellfish harvesting for weeks or months.
In 2014, Friends of Casco Bay participated in the Maine Ocean Acidification Study Commission, which issued a report to the Legislature in January 2015, recommending many actions to confront this threat to our fisheries, including establishing an ocean and coastal acidification council. Efforts in 2015 to pass a law creating the council failed to garner government support.
Rather than letting a worthwhile idea die, Friends of Casco Bay, the Island Institute, and University of Maine/Maine Sea Grant formed the Maine Ocean and Coastal Acidification Partnership (MOCA) to coordinate the efforts of government agencies, private organizations, and citizens. Since its first meeting in March 2016, MOCA has held two symposia, organized working groups, and met with coastal legislators.
Outreach events and coordinated water monitoring are planned for 2017.
What can you do about coastal acidification?
Eliminate the use of fertilizers on your property
Make sure your septic system is doing its job
Reduce carbon emissions by driving less
Support clean energy policies
Opt for meatless Mondays – or more. Eating vegan reduces greenhouse gases significantly
With increasing research showing that coastal acidification is a threat to Casco Bay, here’s what we’re doing about it.
Why do scientists and sea farmers worry about acidifying seawater? Studies by researcher Dr. Mark Green and oyster grower Bill Mook have found that increasing the acidity of seawater can stress sea creatures such as clams, oysters, and mussels. Some shellfish farmers in Maine have already begun storing seawater to use during times when stormwater runoff makes the water unsafe for developing oysters.
Climate researchers have found that the ocean absorbs over 25% of the carbon dioxide released into the atmosphere by smokestacks and tailpipes. This is called ocean acidification. In addition, carbon dioxide ends up in coastal waters from nitrogen pollution from fertilizers, pet wastes, stormwater runoff, and sewage discharges. This nitrogen overdose stimulates a population explosion of tiny phytoplankton. When these plants die and decay in bays and coves, bacteria consume oxygen and release carbon dioxide. This creates even more acidic conditions for coastal critters. This is called coastal acidification.
Dr. Mark Green of St. Joseph’s College in Standish, Maine, is a leading researcher on the impact of coastal acidification on clams. He has been testing how baby clams respond to mud from clam flats along our coast, including Casco Bay. He calls clams the “canaries in the coal mine.” Nitrogen runoff, he asserts, is hampering the ability of clams and oysters to build and maintain their shells. Dr. Green found that clam spat and baby clams simply dissolve at levels of acidity found in some parts of Casco Bay today. He calls this unfortunate condition “death by dissolution.”
Dr. Green’s experiments in the lab inspired us to investigate conditions in Casco Bay. In 2011, we sampled the pH (acidity) of the mud on about 30 clam flats around Casco Bay. In 2012 and 3013, we returned to one of those clam flats to monitor conditions every two weeks across three seasons and varied tide cycles to get a better understanding of how natural fluctuations impacted pH. We also put baby clams (spat) into “clam condos” into a clam flat in Freeport, protected from green clams by screens. After one week and two weeks in the mud, we found significant pitting in their shells, indicating that the shells were dissolving.
Coastal Acidification is one more stressor for shellfish species that already are challenged by other climate change impacts, such as predation by gluttonous milky ribbon worms and green crabs which flourish in warming waters. Red tides or other harmful algal blooms may close clam flats to shellfish harvesting for weeks or months each year. The density and duration of these harmful bloom events may be exacerbated by nitrogen runoff, which provides the nutrients to nourish the red tide organisms.
What are we doing about coastal acidification?
The good news is that we can do something to fight back against coastal acidification caused by nitrogen pollution. Says Casco Baykeeper Ivy Frignoca, “It’s wonderful to work with so many scientists, harvesters, and policy makers who understand this issue and are working on it before coastal acidification becomes insurmountable.”
One way is to find out what we know and what we need to know about coastal and ocean acidification. Friends of Casco Bay and others realized we need a concerted effort to fight the effects of ocean and coastal acidification. In 2014, we participated in the Maine Ocean Acidification Study Commission, which issued a report to the Legislature in January 2015, recommending many actions to confront this threat to our fisheries and marine ecology in general, including establishing an on-going ocean and coastal acidification council.
Friends of Casco Bay worked with the Island Institute and University of Maine/Maine Sea Grant to create the Maine Ocean and Coastal Acidification Partnership (MOCA). MOCA volunteers partnership seek to:
Implement recommendations of the Ocean Acidification Study Commission; and
Coordinate the work of governmental agencies, private organizations, and citizens who are studying and implementing means to reduce the impacts of or help adapt to ocean and coastal acidification.
Here are some highlights of MOCA:
March 14, 2016
MOCA held its first meeting, attended by more than 30 scientists, policy makers, and harvesters.
June 29, 2016
MOCA hosted a day-long Ocean Acidification Symposium, attended by 110 people, including some of the state’s top researchers and policy makers. Scientists shared their field experiment data and compared notes.
November 16, 2016
MOCA hosted a second symposium focused on remediation and policy. More than 50 people gathered at the State House in Augusta to discuss the possibility of developing state/ federal water quality criteria related to coastal acidification. Ivy discussed how we might use existing regulatory tools to reduce nitrogen pollution that exacerbates coastal acidification. The participants formed subcommittees to create an action plan on next steps for confronting ocean acidification through research and legislation.
Education Casco Baykeeper Ivy Frignoca is working with the MOCA Policy Subcommittee to help organize two MOCA symposia in 2017. They will educate interested citizens and decision makers on cutting-edge science and local and state policies that may be implemented to combat acidification
Uniform data collection is the goal of Friends of Casco Bay Research Associate Mike Doan and more than a dozen other scientists on the MOCA Monitoring Subcommittee. They will work together to coordinate and standardize monitoring equipment and procedures on data collection on acidification. This uniformity will provide better understanding of nitrogen inputs into coastal waters.
What can you do about coastal acidification?
Cut down or eliminate fertilizers on lawns, gardens, and farms.
Lobby for and support a town ordinance to limit the use of nitrogen-rich fertilizers.
Reduce rainwater runoff and improve sewage treatment.
Make sure septic systems are doing their job.
Join and/or volunteer with organizations to monitor coastal waters and educate the public.
Reduce carbon emissions by driving less or driving a less polluting vehicle
Support clean energy production such as solar and wind power
Support clean energy policies such as RGGI and the Clean Power Plan
Imagine working 8,760 hours a year. Friends of Casco Bay has two water quality monitors that do just that: a datasonde, an instrument that can measure several properties of water at once, and a specialized device that only measures carbon dioxide. They are anchored together on the ocean floor in Yarmouth to collect data once an hour, every hour, year round. Appropriately, these high tech tools comprise our new Continuous Monitoring Station. These hard workers have been in place since July 2016.
Why is this hourly data vital?
The steady flow of data our Continuous Monitoring Station collects will help us detect and document how climate change and other emerging coastal stressors may (or may not) be affecting the Bay. Hourly data will help us identify daily, seasonal, and annual trends and better understand the extent to which ocean acidification may be impacting the water chemistry of Casco Bay. The station may also help us assess sea level rise. The station collects data on oxygen levels, carbon dioxide (CO2), pH (the level of acidity of the water), salinity, temperature, chlorophyll, and water depth.
In order to ensure continuous data, we have two datasondes which are swapped and refreshed every two weeks. When he arrives at the dock in Yarmouth, Research Associate Mike Doan has less than an hour to reposition the alternate datasonde so that we don’t miss any of those 8,760 hours of information.
Mike hauls up the anchored devices, uploads data from the CO2 sensor to his laptop, and scrapes off marine hitchhikers such as sea stars, tunicates, and algae. “It’s amazing how fast sea creatures occupy any available surface, including our instruments!” says Mike. Before he leaves, he replaces the datasonde with one freshly calibrated and lowers the entire Continuous Monitoring Station back onto the ocean floor. Such attention to detail provides quality assurance that the data is accurate.
While this station is busy year around, we continue to enlist volunteers to help us understand the overall health of our marine waters and to identify troubled areas of the Bay. From April to October each year, more than 90 volunteer Citizen Stewards monitor scores of shoreside sites where they measure five parameters of the surface water: pH, salinity, water temperature, water clarity, and oxygen level. If you are interested in becoming a water quality monitoring volunteer, you can learn more about the program here.
Our volunteers, staff scientists, and now our automated partners, all play a role in helping us to better understand what is going on in Casco Bay.
Thank you to funders of this project, including Casco Bay Estuary Partnership, Davis Conservation Foundation, Horizon Foundation, Schwartz Family Fund of the New Hampshire Charitable Foundation, and WEX. We also thank our Members and the many donors, local businesses, and foundations that give us operational support to do our work each year.
At the annual Labor Day clambake on Little Diamond Island, Althea and her sister Priscilla help out at the end-of-the-season event that draws the community together for a farewell to summer. While the lobsters, sweet potatoes, sausages, and corn are roasting in a fire pit outside the hundred year-old Casino, their job is to wash and de-sand freshly harvested Casco Bay clams.
Althea recalls scooping huge handfuls of clams into 8 heavy kettles to steam them for the feast. Nowadays, they have to place the clams into the pot delicately, or else the shells may end up chipped or even shattered. Althea says that the clams they buy now are smaller and more fragile than the ones she
recalls from years back.
Althea’s observations seem to correspond to observations Friends of Casco Bay has been making over the years. We are studying Coastal Acidification, the problem of increasing acidity from the ocean absorbing carbon dioxide released by the burning of fossil fuels, and, we believe, from excess nitrogen washing into coastal waters by stormwater runoff. Fertilizers, sewage discharges, and pet wastes trigger algae blooms that add excess carbon dioxide to coastal waters.
Our data shows that the acidity of Casco Bay has increased since we began our water quality monitoring program nearly 25 years ago. In 2011, we began sampling the pH (acidity) of mudflat sediments, where soft-shell clams live. We found that the mud nearest to shore was more acidic (had lower pH) than sediments further away from sources of land-based pollution. Higher acidity makes it harder for shellfish to extract calcium carbonate from their environment, the material that clams, mussels, and other mollusks need to build and strengthen their shells.
In the summer of 2014, Friends of Casco Bay installed several clam “condos” in the intertidal mudflats of Recompense Bay in Freeport. Our goal was to see what would happen when we exposed juvenile clams to acidic mud. Research Associate Mike Doan caged baby clams inside PVC tubes and left them in the mud for several days. Microscope photographs of the tiny clam spat showed that after just one week, their shells had become pitted, showing signs of dissolving.
The Health of Casco Bay: The Good, the Bad, and the Ugly
Friends of Casco Bay works year-round on threats to clean water, such as sewage overflows, oil spills, and ocean acidification, as well as green slime, red tides, and dead zones triggered by nitrogen pollution from fertilizers and stormwater runoff. Get an update on the health of our coastal waters and learn how Casco Bay is changing.
Save the Steamers! How coastal acidification is killing our clams
Why are shellfish disappearing in parts of Casco Bay where they were once plentiful? Some clam flats are becoming more acidic, clammers can no longer find clams in traditional harvesting areas, and aquaculturists are seeing seed clams dissolve. What’s up with that?
Casco Bay Begins in Your Backyard: How to have a green yard and a blue bay
After finding pesticides and fertilizers flowing into the Bay, Friends of Casco Bay launched BayScaping, a lawn care program that doesn’t rely on toxic chemicals. Find out why our ocean-based organization is working with neighboring communities to limit or stop their use of pesticides and fertilizers on land.
Fighting Plastic Pollution
Most of are aware that plastic products can harm seabirds, dolphins, whales, and sea turtles, when they mistake plastic bags for food or become entangled in fishing gear. Now people are learning that the smallest form of plastics—microbeads—are having an unexpected impact. Microbeads can be found in shaving cream, facial scrubs, and cosmetics. They are so tiny that when they wash down the drain, they can go right through our wastewater treatment plants and into streams and rivers, and end up in our coastal waters. Microbeads absorb toxic chemicals and are ingested by shellfish, causing a health risk to humans. What can be done to stop plastic pollution? Lots!
Nabbing Nitrogen: Help Us Test the Health of the Bay
If you’d like to be a citizen scientist for a day, join us for an hour on the morning of Sunday, July 10, 2016. We plan to mobilize volunteers to help us learn more about nitrogen levels in Casco Bay. Volunteers will collect water samples at sites around Portland Harbor and bring them to designated collection sites to be sent to a lab for analysis. We will use this day of action—and the results—to educate people about Nitrogen Pollution, help the Maine Department of Environmental Protection collect valuable data, and shine the public spotlight on an issue too few understand. Find out how you can help!
All living things need nitrogen to grow. Nitrogen stimulates the growth of plants—both on land and in the ocean. In the marine environment, nitrogen jumpstarts blooms of algae—seaweed and phytoplankton, the tiny plants that form the base of the ocean food chain and provide half the oxygen we breathe. But an overdose of nitrogen triggers excessive growth of nuisance, and even harmful, algae. As these plants decay, bacteria take oxygen out of the water and release carbon dioxide into our coastal waters.
The map below shows concentrations of nitrogen around the Bay. There is a very clear trend of decreasing nitrogen away from shore. This indicates that land-based sources are contributing excess nitrogen to our waters. The farther offshore, the better the water quality!
As our coastal waters become more acidic (as the pH decreases), clams, mussels, and other shellfish are having a harder time building and maintaining their shells. Juvenile clams may dissolve outright. Our research has found a disturbing link between acidic mud and clam flats where it is no longer profitable for clammers to harvest shellfish.
In 2011, Friends of Casco Bay began to publicize and investigate coastal acidification. We developed a scientific procedure for sampling the acidity of mud on clam flats. We wanted to compare the pH of clam flats that are actively being harvested by clammers to those that are no longer productive.
This groundbreaking work assesses how acidified sediments threaten the survival of baby clams in Casco Bay. Three years of data show that areas with the highest acidity (lowest pH) are the same flats where clams are now scarce.
We found a strong correlation between high levels of nitrogen and carbon in the mud—indicating organic matter— and lower pH. In other words, a lot of dead, decaying stuff makes matters worse.
Many people are interested in the results of our cutting- edge coastal acidification research, including the 1,700 registered Maine diggers who support a $16.8 million-a-year industry harvesting soft-shell clams. Those of us who define summer as a delicious plate of steamers have a gastronomic interest, too!
While Casco Bay is still a thriving ecosystem, it is changing, and more rapidly than we might expect. In some years, lobster populations appear to be moving inshore and molting earlier.
Soft-shell clams, Maine’s third largest fishery (after lobsters and elvers), face an uncertain future. As both the waters and the mudflats of Maine become more acidic, our valuable marine resources find themselves in an increasingly inhospitable environment. Friends of Casco Bay has confirmed that coastal acidification is altering the very mud in which juvenile clams, mussels, and oysters are attempting to establish a foothold.
Clammers say that green crabs are overrunning our clam flats, devouring juvenile clams, and devastating many formerly productive clam flats in Casco Bay and beyond. Green crabs from Europe invaded our coastal waters in the early 1900s. Now, a species of green crab from Scandinavia is beginning to show up in Maine waters, probably well equipped to adapt to our cold winters.
In the mid-1990s, Casco Bay had approximately 8,700 acres of eelgrass beds, the largest and densest concentration of eelgrass along the entire coast of Maine. A 2013 aerial survey of Casco Bay, initiated by Casco Bay Estuary Partnership and Maine Department of Environmental Protection, found only about 3,700 acres, a nearly 60% decline in eelgrass beds since 2001, primarily in the embayments of Maquoit and Middle bays.
What does this mean for those of us who live, work, and play around the Bay? We have a lot of work to do. Fortunately, unlike some environmental problems, there are many things each of us can do to tackle threats to the health of Casco Bay.
Learn more about our coastal future by watching these presentations from our Casco Bay Is at Risk event which took place on September 24, 2014.