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What was your favorite Casco Bay moment of 2021?

As this year comes to an end, let’s reflect and celebrate the many ways that we worked together to protect the health of Casco Bay in 2021. Here are our top ten stories of the year:

1) We crossed the finish line on our Climate Change and Casco Bay Fund. More than 700 Friends of the Bay contributed $1.5 million to the Climate Change and Casco Bay Fund for Technology, Monitoring, and Community Engagement. These funds enabled us to launch two new Continuous Monitoring Stations in Casco Bay and will support the maintenance of all three of our stations for the next decade.

Mike deploys our Portland Harbor Continuous Monitoring Station
Mike deploys our Portland Harbor Continuous Monitoring Station

2) We launched two new Continuous Monitoring Stations. With the Climate Change and Casco Bay Fund completed, we launched two new Continuous Monitoring Stations in Casco Bay! This past spring, our new stations splashed down in Harpswell and Portland Harbor, and Staff Scientist Mike Doan walked us through their preliminary data.

3) We successfully advocated for forward-looking climate change legislation Augusta. We were thrilled to see Maine pass legislation to adapt our stormwater, land use, and planning laws to incorporate climate change projections, a top priority of Maine’s Climate Action Plan. Scores of Friends submitted testimony in support of “LD 1572 Resolve, To Analyze the Impact of Sea Level Rise.” If you were one of them, thank you!

4) We celebrated the career and contributions of Cathy Ramsdell. Our former Executive Director, Cathy Ramsdell, retired in September after 18 amazing years at the helm of Friends of Casco Bay. We hosted an outdoor celebration in honor of Cathy at Portland Yacht Services on August 26. At the event, staff and board members shared reflections on Cathy’s leadership and Gulf of Maine poet Gary Lawless read his poem, “For Casco Bay, for Us.”

5) Water Reporter Rick Frantz revealed the impacts of erosion. We have all heard that a picture is worth a thousand words, but have you ever seen a photo that is worth 17 years? Volunteer Water Reporter Rick Frantz compared photos of Diamond Cove Beach from 2004 and 2021 to reveal the slow work of erosion over nearly two decades.

6) We supported many legislative victories for Maine’s environment and Casco Bay. Casco Bay will be cleaner and healthier, and our communities will be safer due to the many environmental victories passed in Augusta this year. Issues facing the Bay that are being addressed by new policies and laws include: sea level rise, expired marine flare disposal, changing eelgrass and salt marsh habitat, and public coastal access.

Volunteer Water Reporters and Friends of Casco Bay staff visited two Brunswick salt marshes in early September, where they shared observational insights and discussed local ecology.

7) Water Reporters documented an eelgrass mystery in Casco Bay. Volunteer Water Reporters observed an increase in torn and uprooted eelgrass in Casco Bay between August and September. Eelgrass is critically important to the health of the marine environment as it supports fisheries, maintains water quality, and acts as a carbon sink.

8) Staff Scientist Mike Doan showed us how phytoplankton affect the Bay. Many factors cause seasonal changes in Casco Bay. The activity of phytoplankton is one of them. Looking at data from our Continuous Monitoring Stations we see how these microscopic plants at the base of the marine food web can dramatically change the levels of acidity, oxygen, nutrient availability, and other factors in the Bay.

9) We monitored and supported cleanup efforts after an oil spill closed Willard Beach. It has been a rough few months for Willard Beach in South Portland. In addition to a sewer main break in October, Willard Beach was closed for three days at the end of August to accommodate cleanup efforts and protect public health from an oil spill. Casco Baykeeper Ivy Frignoca toured the site of the spill and commended the cleanup efforts led by state, local, and private agencies.

10) Water Reporters learned about oil spills and algal blooms from regional experts. Volunteer Water Reporters connected with regional experts from National Oceanic and Atmospheric Administration (NOAA) and Maine Department of Marine Resources in an illuminating discussion about identifying and reporting oil spills and algal blooms seen on Casco Bay.

We look forward to keeping you updated in the New Year. Thank you for being a Friend of Casco Bay.

How does something so tiny drive change in the Bay?

What factors drive seasonal changes in the waters of Casco Bay?

Staff Scientist Mike Doan addresses this question by looking at recent data from our Continuous Monitoring Stations in our latest Mike’s Field Notes video.

Our Continuous Monitoring Stations collect data hourly on a variety of key water quality and climate change indicators across Casco Bay. Understanding the ways that climate change is impacting the Bay requires many years of data. As we work to collect these long-term data sets, we need to become familiar with the factors that drive short-term changes in water quality. These short-term changes may occur between seasons, months, or even day-to-day.

The activity of phytoplankton – the microscopic plants at the base of the marine food web – is one factor that influences many of the parameters we track in our Continuous Monitoring data. In this video, Mike breaks down how phytoplankton can influence acidity, as well as the amounts of carbon dioxide and oxygen in Casco Bay.

As always, you can view our Continuous Monitoring Station data on our website.

Thank you for caring about the health of Casco Bay.

An annual spring awakening in the Bay

As winter comes to a close and the days get longer, an annual awakening occurs in Casco Bay.

Populations of phytoplankton – microscopic algae that form the base of the ocean food web – rapidly reproduce as longer days leave more time to harness the sun’s energy for photosynthesis. The spring blooms of these tiny, single-cell life forms have an oversized impact on the ecology and chemistry of our coastal waters.

As phytoplankton populations grow and photosynthesize, they remove carbon dioxide from the water, replacing it with oxygen. Carbon dioxide acidifies water, so the net effect of having more oxygen and less carbon dioxide in the Bay is that our waters become less acidic.

By the time the spring phytoplankton bloom reaches its peak, this burst of biological activity has depleted the Bay of nitrogen and other nutrients essential for growth. Just as suddenly the phytoplankton populations exploded, the blooms die off. As the algae die and decay, the carbon dioxide consumed during photosynthesis is released back into the Bay, once again increasing the acidity of the water.

At Friends of Casco Bay we use our Continuous Monitoring Station to track this seasonal phenomenon. Our high-tech oceanographic instruments take hourly measurements of chlorophyll (the green pigment found in plants and algae that enables photosynthesis), allowing us to estimate the abundance of phytoplankton in the Bay at any time. We also track pH, a measure of the acidity of our waters

We can see the phytoplankton bloom-and-bust cycle in our data. As chlorophyll levels increase in February and March, so do pH levels [pH is measured on an inverse scale; the higher the pH, the lower the acidity]. When the algae blooms die and chlorophyll crashes, so does pH. 

Phytoplankton blooms are just one of many seasonal occurrences that influence the chemistry and pH of Casco Bay: factors like spring snowmelt, rainstorms, and warmer summer waters also have substantial impacts. Understanding this kind of natural variability in water chemistry helps us better discern how our collective actions may be affecting the Bay. From local nutrient pollution sparking harmful algal blooms and the acidification of our coastal waters, to ocean acidification on a global scale, human activity is driving the trend toward more acidic marine environments in Casco Bay and around the world.

Keep an eye out for upcoming stories about acidification in Casco Bay, how it impacts our marine environment, and how you can help us address this pressing issue to protect the health of the Bay for years to come.

Spring Blooms in Casco Bay

What signs tell you that spring has arrived? Grass turning green? A robin in your yard? Ospreys returning to their nests?

What about huge blooms of phytoplankton in Casco Bay?

The chlorophyll fluorescence measurements in the graph above were recorded by our Continuous Monitoring Station, which has been in place for almost two years.

Chlorophyll fluorescence is a measure that provides an estimate of phytoplankton abundance. Chlorophyll is the green pigment in plants that traps the energy of the sun for photosynthesis.

The graph tells us that this year’s spring bloom of phytoplankton started around the same time as last year, but was bigger in magnitude this year than in 2017.

Why do we care about chlorophyll levels? Phytoplankton are the single-celled plants that make up the foundation of the ocean food web. Phytoplankton also provide half of all the oxygen we breath—so thank phytoplankton for every other breathe you take. You can read more about phytoplankton and chlorophyll in our recent post.

Photography by Kevin Morris

Every hour and every day, the Continuous Monitoring Station—a.k.a our “Cage of Science”—is building a more complete picture of the seasons beneath the Bay. Thanks to support from Casco Bay Estuary Partnership and generous donors, the Station collects measurements of temperature, salinity, pH, dissolved oxygen, carbon dioxide, and chlorophyll fluorescence year-round. Every other week, Research Associate Mike Doan cleans and calibrates the equipment, and downloads and graphs the data to track conditions in the Bay.