What is this Cage of Science that Friends of Casco Bay keeps talking about? We invite you to join Staff Scientist Mike Doan out on Casco Bay for a short tour of our Continuous Monitoring Station. In this 2 ½ minute video, Mike shows off the high-tech components of the station and shares why its stream of data is so important to our work.
If you have ever tried to pick the right shade of green to paint your bedroom, you know there are soothing greens and greens you would never want to wake up to. The same holds true in the ocean.
Algae is one of those “greens” that can be a sign of a healthy ecosystem; but large areas of mudflats may become covered in a nightmarish bright green when algal growth is fueled by too much nitrogen in the water.
In 2019, as the water warmed from spring through fall, volunteers in our Water Reporter observing network tracked algal blooms that appeared in 18 different locations around Casco Bay. The photos they took on their smartphones documented changes throughout the summer, as the algal blooms expanded to worrisome levels in many coves from Cape Elizabeth to Harpswell and West Bath.
In 2017, we tracked algal growth at five sites. We do not have enough historical data to know whether nuisance algal blooms are expanding or simply that we are getting better at tracking more sites, thanks to our growing network of Water Reporters.
In any case, nuisance and harmful algal blooms are an increasing concern. Water Reporters are already discovering and tracking sightings in 2020!
Community Engagement Coordinator Sarah Lyman oversees our Water Reporter program. This year, Sarah hopes to recruit additional volunteers to our band of intrepid Water Reporters who track algal blooms. “Each volunteer will adopt a specific Bay location to observe weekly. Images of algae from the ‘good’ amounts to ‘concerning’ amounts are helpful because we can’t predict where and when a small patch of algae may become a nuisance algal bloom.”
Currently, there are 205 volunteers in our Water Reporter network. Together, they have recorded 991 observations about Casco Bay. If you are interested, learn more at cascobay.org/water-reporter.
When we look at our water quality data, we can see that some characteristics of the Bay influence other characteristics. In this example, large phytoplankton blooms have a big impact on the chemistry of Casco Bay.
Ready for some Marine Science 101?
In the graph below, we compare two types of data we collect at our Continuous Monitoring Station: chlorophyll and pH.
We measure chlorophyll to understand how much phytoplankton is in the water. Phytoplankton are microscopic plants that are the base of the food chain. Chlorophyll is the green pigment in phytoplankton (and all plants) that traps the energy of the sun for photosynthesis. Higher levels of chlorophyll indicate an abundance of phytoplankton. Graphs of chlorophyll show when populations of phytoplankton are on the rise and when they crash.
pH is a measure of acidity. The lower the pH, the more acidic the solution. The pH measurement decreases as acidity increases. That is because pH is an inverse measure of the concentration of hydrogen ions in a solution, measured on a scale of 0 to 14. The scale is logarithmic, and each number is an order of magnitude different. For example, a pH of 7 is ten times more acidic than a pH of 8, and one hundred times more acidic than a pH of 9. pH is an abbreviation for “power of hydrogen.” Any solution with a pH lower than 7 has more hydrogen ions than hydroxide ions. Data from our Continuous Monitoring Station show that pH is around 8.0 on average, but changes hourly, daily, and seasonally.
What is this graph telling us?
The graph above compares chlorophyll and pH data from our station. The two lines track the daily means of that data calculated from July 2016 through mid-March 2020.
You can see the variability in both chlorophyll and pH over time, moving from left to right.
When chlorophyll spikes, there is generally an uptick in pH, and then a decrease in pH as chlorophyll levels drop.
Why does this happen?
Whenever carbon dioxide (CO2) is added to water, the water becomes more acidic (pH goes down). The opposite is true as well. Acidity decreases (pH goes up) as CO2 is removed from the water.
When phytoplankton photosynthesize, they convert carbon dioxide (CO2) from the water to carbohydrates and oxygen. This reduces the amount of CO2 in the water, lowering the acidity. The larger the bloom of phytoplankton, and the longer the daylight hours, the lower the acidity (and the higher the pH). Other factors influence pH as well, but the amount of phytoplankton is a primary driver.
As the bloom ends, much of the phytoplankton die and decompose. The process of decomposition releases CO2 to the water and pH levels go down (more acidic water).
Compare changes in chlorophyll and changes in acidity throughout the year here.
Living close to the ocean, Casco Bay residents are witnessing the effects of climate change happening here now: warming water temperatures, increasing ocean acidity, and more severe storms. We too are seeing the changes in our data and when we are out on the Bay.
From April through October, our Research Associate Mike Doan and Casco Baykeeper Ivy Frignoca are on the Bay frequently to monitor water quality, follow up on pollution reports, or meet with partners on issues best understood from the water. Their vigilance gives them a firsthand view of changes happening in our coastal waters.
Mike, Ivy, and Executive Director Cathy Ramsdell shared these and other observations in our first-ever Casco Bay Matters series. Nearly 400 people attended Ocean Acidification, Climate Change and You presentations about what we are learning about a changing Casco Bay.
They shared how Mainers are working together to shape policies and actions to respond to these threats. Ivy is coordinating the Maine Ocean and Coastal Acidification partnership, a diverse coalition of scientists, lawmakers, aquaculturalists, and seafood harvesters, who collaborate on research and strategies to confront the threats that climate change and acidification pose to Maine’s marine resources. We also are working with legislators to pass a bill to create a state-sponsored Science and Policy Advisory Council on the Impact of Climate Change on Maine’s Marine Species.
Video Recordings of Casco Bay Matters:
If you missed our Casco Bay Matters presentations of Ocean Acidification, Climate Change and You, you are in luck — our stalwart volunteer Deb Dawson recorded and edited videos of our South Portland (March 25, 2019) event. See the series of three videos on our YouTube channel.
Highlights from Casco Bay Matters:
Warmer waters: Friends of Casco Bay has been tracking water temperatures for over a quarter century. On average, water temperatures in Casco Bay have risen 2.5°F (1.4°C) since 1993. The growth, reproduction, and survival of marine life are influenced by temperature.
More carbon dioxide in our coastal waters from air and from land: We know that burning fossil fuels adds carbon dioxide to the atmosphere, trapping heat and warming the planet. Nearly 30% of atmospheric carbon dioxide is absorbed by the ocean. Carbon dioxide mixes with water to form carbonic acid, making the water more acidic. This is ocean acidification.
Maine’s nearshore waters are also at risk from coastal acidification. Excess nitrogen from sewage treatment plants, polluted stormwater, and fertilizers can stimulate massive algal growth. When the algal blooms die, decomposition depletes the area of lifegiving oxygen and releases carbon dioxide, further acidifying the water.
Threats to the ocean food web: More carbon dioxide in our waters means less shell-building material (calcium carbonate) for clams, mussels, and planktonic creatures that support the ocean food chain. Data from our Continuous Monitoring Station enable us to calculate the calcium carbonate saturation state — what scientists term omega aragonite — which can tell us whether, at any given time, enough calcium carbonate is readily available to shell-building creatures. Shell formation becomes more difficult for some species when the amount of available calcium carbonate falls below a 1.5 aragonite saturation state.
Sea level rise: As water warms, it expands, and the seas encroach on our coastline. Coastal observers and property owners are reporting more erosion.
Increasing precipitation: Maine has seen a six-inch rise in average annual precipitation since 1895, further threatening coastal properties. Torrential rains intensify erosion and flush overloads of nitrogen, pollutants, and sediments into coastal waters.
On July 20, 2016, our Continuous Monitoring Station began recording data hourly, 365 days a year. We are excited to share the first two and half years of data, collected at our water quality monitoring site in Yarmouth, near the coastal midpoint of Casco Bay. We will update these graphs monthly, so come back often and see for yourself how Casco Bay is changing.
Watch this short video about the Cage of Science!
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.
Thanks to support from Casco Bay Estuary Partnership and generous donors, our Continuous Monitoring Station collects data once an hour, every hour, year round.
As always, Casco Baykeeper Ivy Frignoca has been on the move, working across Casco Bay, the state—and the nation—on efforts to protect the environmental health of Casco Bay.
A peek into her appointment calendar shows some of the highlights so far this year, as she continued to track Legislative issues and to comment on proposed wastewater and stormwater discharge permits that the Department of Environmental Protection issues to municipalities.
I became coordinator of the Maine Ocean and Coastal Acidification Partnership (MOCA) for 2018.
I will help coordinate research and advocacy on ocean acidification with a strong statewide network of policy makers, fishermen, shellfish growers, and scientists. This year-long role supports our work examining coastal acidification and excess nitrogen.
I invited Portland’s Water Resources Manager, Nancy Gallinaro, and Portland Water District’s Director of Wastewater Services, Scott Firmin, to travel with me to meet the new Environmental Protection Agency (EPA) Region 1 Administrator, Alexandra Dapolito Dunn. We highlighted our joint efforts to reduce nitrogen pollution, combined sewer overflows, and stormwater pollution to Casco Bay. I shared our data showing the impacts of climate change on Casco Bay.
Administrator Dunn accepted our invitation to come to Maine in June to attend a meeting of the Maine Nutrient Council, a group convened by Casco Bay Estuary Partnership. Afterward, Administrator Dunn will tour the Bay on our Baykeeper boat, a great opportunity for a close-up view of issues that threaten the water quality of Casco Bay.
I traveled to Washington, DC, at the invitation of Ocean Conservancy, to meet with our Congressional delegation and ask for full funding for the National Oceanic and Atmospheric Administration and the EPA. The measures we pressed for passed in the omnibus budget!
Back in Maine, I submitted comments opposing offshore drilling and then attended a meeting hosted by the Bureau of Ocean and Energy Management, to voice Friends of Casco Bay’s opposition to offshore drilling. I supported a resolve that was passed unanimously by our state legislature expressing its opposition to offshore drilling.
I testified at a public hearing as we worked to swiftly defeat a bill that would have practically eliminated the ability of municipalities to pass pesticide ordinances. If you contacted legislators after receiving our email alert about this issue, thank you! The bill was defeated!
I traveled to New Hampshire to attend a meeting of experts concerned about the rise in harmful algal blooms throughout the region, so we could learn more about new species appearing in Casco Bay.
I attended a meeting in West Bath, which drew together people who live and work along the New Meadows River, to discuss how expanding efforts in aquaculture may figure into the many uses of the estuary.
Research Associate Mike Doan gave Kate Simpson and Kayla McMurray, staffers for Senator Susan Collins, a ride to our Continuous Monitoring Station in Yarmouth. I met them at our “Cage of Science” as we demonstrated how we use technology to monitor the Bay hourly, 365 days a year. We explained that though we do not receive funding directly from the EPA, the Agency has a vital role in advising state regulators on strategies to reduce pollution, funding other research, and enforcing the Clean Water Act. This work helps us all protect the environmental health of Casco Bay.
The Portland Water District (PWD) hosted a ribbon-cutting ceremony to celebrate the completion of the massive, $12 million project that upgraded the aeration system at the East End Wastewater Treatment Facility. This improvement could ultimately reduce nitrogen in the treated sewage released into the Bay by up to 1000 lbs. a day! PWD’s General Manager Carrie Lewis recognized our contribution “to understanding the issues affecting Casco Bay and make positive contributions towards collaborative solutions.”
The Maine Ocean and Coastal Acidification Partnership (MOCA) is a volunteer partnership that seeks to coordinate the work of governmental agencies and private organizations and citizens who are studying and implementing means to reduce the impacts of or help adapt to ocean and coastal acidification.
With my colleagues in the MOCA Partnership, I hosted a workshop for nearly 60 scientists, harvesters, policy makers, and advocates on What We Know about Ocean Acidification and Maine’s Lobsters. The event at Bowdoin College featured current research on the effects of climate change on lobsters and emphasized the need for ecosystem-level, long-term studies.
As the year progresses, I look forward to continuing to keep you updated on the biggest issues affecting the health of the waters we all love.
Covered with sea squirts, sea stars, and other marine hitchhikers, the newest member of our monitoring team looks like an abandoned lobster trap. It may be homely, but we are pretty impressed with what it does, collecting water quality data hourly, 24 hours a day, 365 days a year. It is our Continuous Monitoring Station, which will help us answer the question “How are our coastal waters changing over time?” Research Associate Mike Doan calls it “the cage of science.”
It has been just over a year since we placed a carbon dioxide sensor and a data sonde—an electronic device that records temperature, pH, and other characteristics of water quality—inside this modified lobster trap and moored it in healthy waters near the center of Casco Bay off Cousins Island in Yarmouth.
After one full year, we have over 8,760 hours of data on oxygen levels, carbon dioxide, pH (the level of acidity of the water), salinity, temperature, chlorophyll fluorescence (estimated phytoplankton abundance), water clarity, and water depth.
Thanks to our 26-year data set on water quality in Casco Bay, we understand when and which areas of the Bay are likely to exhibit challenged water quality conditions that require further study. Armed with this baseline data, we can now consider how to address the question, How is the Bay changing?
The steady flow of data from the Station already is helping us detect and document how climate change and emerging coastal stressors may be affecting the Bay. Hourly data helps us identify daily, seasonal,
and annual trends to better understand the extent to which ocean acidification may be impacting the water chemistry of Casco Bay. In future years, we hope to deploy two more “cages of science,” one in challenged waters in Portland Harbor and one near Harpswell to help detect the influence the Kennebec River has on Eastern Casco Bay.
What is a data sonde?
A data sonde, such as the one being used by Research Associate Mike Doan, is an oceanographic
monitoring instrument that takes multiple measurements of water quality simultaneously. In
addition to being used as part of our Continuous Monitoring Station, data sondes are used by
staff scientists in other water quality monitoring efforts from shore and by boat. The data is
downloaded to a computer and analyzed to provide a long-term picture of water quality over
time. We thank Casco Bay Estuary Partnership and our generous members for helping fund
our Continuous Monitoring Station’s first year.
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
- Find out more actions you can take at here.