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Crabs, HABs, Sharks, and More… A Casco Bay Matters Event

Great white shark image provided by Matt Davis, Maine Department of Marine Resources

Join us next Wednesday for an illuminating discussion with guest scientists who are doing cutting edge research in Casco Bay: Crabs, HABs, Sharks, and More… A Casco Bay Matters Event.

Green crabs, harmful algal blooms (HABs), and great white sharks are drawing increasing attention around Casco Bay. Have these sea creatures always been here? Is climate change influencing their presence? 

Changes in coastal chemistry are impacting shellfish populations, while rising seas and other forces are eroding salt marshes. What can we do to protect our vital resources and habitats?

Find out answers to these questions by joining Staff Scientist Mike Doan and Casco Baykeeper Ivy Frignoca as they moderate a panel of guest scientists sharing their research on each of these topics in Casco Bay. All panelists will be available to answer your questions after their presentations.


Our panel of guest scientists includes: 

Matt Davis, from Maine Department of Marine Resources, monitoring great white sharks

Sara Randall, from Downeast Institute, researching shellfish and coastal chemistry

Marissa McMahan, from Manomet, studying invasive green crabs

Bryant Lewis, from Maine Department of Marine Resources, tracking harmful algal blooms

Matt Craig, from Casco Bay Estuary Partnership, restoring salt marshes


You must register to join this event. We would love for you to join us. 

Register Now

Testimony in support (with amendments) of LD 1679: An Act To Establish the Maine Climate Change Council To Assist Maine To Mitigate, Prepare for and Adapt to Climate Change (Governor’s bill)

May 17, 2019

Senator Carson
Representative Tucker
Committee on Environment and Natural Resources
c/o Legislative Information Office
100 State House Station
Augusta, ME 04333

Re: Friends of Casco Bay and Maine Ocean and Coastal Acidification (MOCA) Steering Committee testimony in support (with amendments) of LD 1679: An Act To Establish the Maine Climate Change Council To Assist Maine To Mitigate, Prepare for and Adapt to Climate Change (Governor’s bill)

Dear Senator Carson, Representative Tucker, and Distinguished Members of the Environment and Natural Resources Committee,

Introduction to Support for Bill with Amendments:
Friends of Casco Bay and the Steering Committee of the Maine Ocean and Coastal Acidification (MOCA) partnership submit the below testimony in support of LD 1679, An Act To Establish the Maine Climate Change Council To Assist Maine To Mitigate, Prepare for and Adapt to Climate Change (Governor’s bill). We support the bill but recommend four amendments to better address the impacts of climate change to Maine’s marine species and habitats. These amendments are set forth in the attached track-changes document and below:

  • Amend Section 11 (38 MRSA § 578) – which requires the Council or Department to provide evaluation reports to this Committee and the Energy, Utilities and Technology (EUT) Committee – to also require reports to the Marine Resources Committee (MRC) and to authorize the MRC to make recommendations to this Committee.
  • Amend Section 10 (38 MRSA §577-A) (8) to include recommendations for scientific monitoring and research to fill data gaps needed to spur action or evaluate remediation and adaptation strategies.
  • Amend Section 10 (38 MRSA §577-A) (6) to specify that the Scientific Subcommittee should provide technical support to the working groups and should contemplate creating subgroups of experts to support the working groups.
  • Amend Section 10 (38 MRSA §577-A) (1) to include representation by a fisherman and by an aquaculturist.

Who We are:
Friends of Casco Bay is a nonprofit marine stewardship organization dedicated to improving and protecting the environmental health of Casco Bay. We scientifically monitor and assess water quality, including parameters indicative of climate change and ocean acidification. We employ a Casco Baykeeper, who serves as the lead advocate, or eyes, ears and voice of the Bay. We engage in significant public outreach including citizen science and other actions to engage our members and volunteers in our work to improve the health of the Bay.1

Maine Ocean and Coastal Acidification (MOCA) is a voluntary partnership formed to implement recommendations of the Ocean Acidification Study Commission authorized by the 126th Legislature (see study commission’s report).2
Friends of Casco Bay, the Island Institute, and Maine Sea Grant convened MOCA when the State failed to establish an on-going council to implement the Study Commission’s recommendations. Friends of Casco Bay has served on the MOCA Steering Committee since its inception and as its Coordinator for the last two years. MOCA has been most effective as an interim forum for coordinating and sharing research among public and private entities and as an information exchange.

Testimony on the Marine Aspects of LD 1679:
We support the overall concept of working across sectors to mitigate and adapt to climate change. Because our expertise is with respect to the health of marine waters, we will confine our testimony to those aspects of the bill.

To paraphrase Governor Mills’ inaugural address, we must act now. Climate change is already impacting Maine’s fisheries and habitats:

  • About a third of all carbon dioxide emitted into the atmosphere is absorbed by the ocean, where it mixes with sea water to form carbonic acid and lower pH. This process is known as ocean acidification. In Casco Bay, pH has dropped from 8 to almost 7.8 from 2000-2012. The pH scale is logarithmic, meaning that a decrease of an integer value changes the concentration by tenfold. Lower pH (more acidic water) can cause mollusk shells—including clams, oysters, and mussels—to pit and dissolve.
  • Annual precipitation in Maine has increased six inches since 1895, and we are experiencing more intense storms that deliver excess nitrogen to marine waters. The nitrogen fuels algal and phytoplankton blooms. The blooms have immediate negative impacts on marine species. For example, we have seen thick mats of nuisance algae smother clams. In addition, as blooms die, they release carbon dioxide which mixes with sea water to form carbonic acid. This process is known as coastal acidification and also lowers the pH of our coastal waters.
  • The temperature of Casco Bay rose about 1 degree Celsius (2.5 degrees Fahrenheit) from 1993 to 2018. Warmer ocean temperatures mean that green crabs are not dying back over the winter. The higher populations of green crabs prey on soft-shelled clams and other mollusks. They also demolish eelgrass beds, a critical marine habitat. Rising ocean temperatures also cause shifts in species and can contribute to an increase in lobster shell disease.
  • In 2016, we began measuring the amount of calcium carbonate available for mollusks and other organisms to build their shells. We learned that for most of the year, there is not enough calcium carbonate in the water for shell-building.

Prior to news that Governor Mills would introduce her comprehensive Climate Change Council bill, Representative Lydia Blume worked with MOCA to draft LD 1284: An Act To Create the Science and Policy Advisory Council on the Impact of Climate Change on Maine’s Marine Species. The MRC held a hearing on that bill on April 2, about a month before the Governor’s bill was printed.

135 people from Friends of Casco Bay, MOCA, and other entities submitted testimony in support of LD 1284. No one testified against the bill. The Environmental Priorities Coalition selected the bill as a priority; industry leaders such as Mook Sea Farm and the Maine Aquaculture Association supported the bill; and leading marine research institutes, including Gulf of Maine Research Institute, Island Institute, Downeast Institute, and University of Maine, offered their support. The Ocean Conservancy‘s CEO sent a letter of support and separately authorized retired Congressman Tom Allen to appear and testify on their behalf.3

Commissioner Keliher testified and asked the MRC to delay further consideration of LD 1284 because the Governor intended to incorporate it into her bill. The MRC honored that request. We have reviewed and support LD 1679; it incorporates most of the intent of LD 1284 but fails to require progress reports to the MRC and afford opportunities for the MRC to make recommendations to this Committee.

We respectfully request that you amend the bill in that respect, and consider and address the other suggested amendments and comments on the attached track-changes document. Thank you for your attention to our testimony.

Ivy Frignoca
Casco Baykeeper
Friends of Casco Bay

A PDF of this testimony and the attachments can be found here.

1 For more information about Friends of Casco Bay, please refer to our website: https://www.cascobay.org/.
2 For more information about MOCA, please refer to: https://www.seagrant.umaine.edu/extension/maine-ocean-andcoastal-acidification-partnership.
3 This link directs you to the testimony submitted in support of LD 1284:

Althea McGirr at LIttle Diamond Island

Althea Bennett McGirr says, “It shucks to be a clam!”

Althea McGirr at LIttle Diamond Island
Althea Bennett McGirr, a Board member since 2011, doesn’t need Friends of Casco Bay to tell her that the chemistry of Casco Bay is changing. She has seen the effects of Coastal Acidification firsthand.

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.

Pitted Clam
The pitted shell shows that life can be tough for a clam spat in acidic mud.

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.

They say a picture is worth a thousand words

This photograph generated many thousands more.

Photo credit: Instagram’s @mainedrone

On July 27th, a photograph on Instagram drew the attention of our in-house social media expert Sarah Lyman. She messaged Maine Drone, asking if the photographer might be interested in flying a drone over Back Cove in Portland. We wanted to document a disturbing development that our Executive Director Cathy Ramsdell first had noticed a few weeks earlier. As soon as Sarah posted this photo, people began reporting slime-covered coves elsewhere. The image generated inquiries about Green Slime from print, radio, and TV reporters.

Abundant sunshine and high temperatures, along with ample amounts of nitrogen, created ideal conditions for thick mats of green algae to flourish, to the detriment of sea creatures underneath. Our own photos show that beneath the green algae, mud dwellers are struggling to survive in low oxygen and high acidity.

These photos show our summer intern Josh Clukey at Mill Cove, South Portland with slime and a dead clam.

Five things you need to know to be a great Friend to Casco Bay


1.) Did you know that what we put on our lawns is showing up in Casco Bay?

In the summer of 2005, Mike Doan, Research Associate at Friends of Casco Bay, opened an envelope and gasped.  Before him appeared a table of laboratory numbers, an analysis of a sample of stormwater Mike had collected a month earlier, from the end of a pipe in Back Cove.  The readings for 2,4-D, a primary component in weed and feed products, were at the highest levels he’d seen yet in stormwater samples.  This herbicide has been classified by the World Health Organization as a possible carcinogen.

The sampling was part of our work in BayScaping, our effort to document that lawn chemicals are going into Casco Bay and to educate residents about strategies for achieving a chem-free lawn. Between 2001 and 2009, we collected rain water flowing into the Bay and analyzed the samples for a suite of pesticides. Lab results identified 7 different pesticides in 13 locations all around the Bay.

Now several municipalities are considering ordinances to restrict or ban pesticides and fertilizers. We are sharing our data and point out that fertilizers are of equal concern.


2.) Do you know why it shucks to be a clam?

When it rains, nitrogen-laden fertilizers are swept into Maine’s nearshore waters. This nitrogen pollution triggers algae blooms that release carbon dioxide when they die and decay. In seawater, carbon dioxide forms an acid. Acidification changes the chemistry of the water, inhibits shell growth in clams, mussels, oysters and other marine organisms, and is suspected as a cause of reproductive disorders in some fish.

We are encouraging communities to consider banning high-nitrogen fertilizers and weed and feed products, which contain both pesticides and fertilizers. Limiting or eliminating the use of fertilizers locally will lower the amount of nitrogen coming in to Casco Bay; this can help slow the devastating effects acidification is having on our marine resources. We are also working on several other projects to reduce nitrogen pollution from sewage discharges and stormwater runoff.


3.) Did you know that discarded hypodermic needles are regularly found on our beaches and marshes?

“Yipes! Here’s another needle!” That is a shout we frequently hear at our beach cleanups. Citizen Stewards Coordinator Peter Milholland rushes over, warning the volunteers not to pick up the discarded hypodermic needles. He uses rubber gloves and tongs to dislodge the needles from the sand or salt marsh. He places them a Sharps disposal kit—basically a plastic box that can hold medical waste—to drop off later at a safe disposal site.

Even though insulin users may use sharps several times a day, the only officially recommended way that residents can dispose of them is to place them in a rigid container, such as a liquid laundry soap container, and toss them in the garbage. When these containers end up in a landfill, they may break open and spill their contents. Many users simply flush them down the toilet. When it rains, overflows of the sewage treatment system can wash the needles into the Bay.

If you should find a sharp, do NOT pick up it up. Notify local police to come pick it up. Should you be pricked by a needle, call the Maine Center for Disease Control at 1-800-821-5821.


4.) Did you know that microbeads are a megaproblem?

Those tiny granules in acne scrubs, moisturizing cleansers, whitening toothpastes, and wrinkle creams wash down the drain and may end up in our waterways. Researchers have found that ocean filter feeders such as mussels and oysters ingest these tiny pellets, passing them all the way up the food chain to humans. Last spring, Friends of Casco Bay, along with concerned citizens, other environmental and health organizations, and even industry representatives, successfully persuaded the Maine Legislature to pass a state law to phase out microbeads.

President Obama recently signed into law a federal ban on microbeads! Emma Halas-O’Connor of the Environmental Health Strategy Center observed, “Congress never could have passed this ban had it not been for individual states passing their own legislation, which put tremendous pressure on the industry to change, and creating the right conditions for a national ban.”


5.) Did you know that populations of blue mussels in Casco Bay are hanging by a thread?

Blue mussels, besides being a delicious and economical seafood for humans, provide a rich habitat for other bottom dwellers. Dense mussel beds also can dampen wave action and buffer the shorefront against storm surges.

Friends of Casco Bay Board member Ann Thayer wanted to verify anecdotal accounts that mussel beds, once so common in Casco Bay, have all but disappeared. Ann offered to head up a volunteer effort to survey the Bay. Over the past two summers, she and her team covered more than 25 areas between Portland and Harpswell. They discovered juvenile mussels on mooring ropes, wharf pilings, and floating docks.  They found far fewer thriving on the ocean floor.

Blue Mussels: Hanging by a thread in Casco Bay

Ann Thayer on boat
Ann Thayer searches for mussel beds along the shores of Casco Bay.

When Ann Thayer goes out in her Boston Whaler, it’s not just to enjoy time on beautiful Casco Bay. This Friends of Casco Bay Board Member is scouting out mussel beds, and more often than not, she is not finding them.

Blue mussels (Mytilus edulis) are the common mussels found along the Maine coast. Ann explains, “In addition to providing a rich habitat for other sea life, dense mussel beds can provide protection to the shorefront against the effects of storm surges. Mussels are filter feeders, and they can siphon up to 25 gallons of water a day as they feed on microscopic algae and nutrients in the water column. In short, they are important contributors to the Bay!”

For the past few years, anecdotal accounts suggest that mussel beds once piled high with layers of living mussels are now all but gone. Ann, an environmental scientist by training, offered to lead a volunteer effort to survey the Bay to see if reports of disappearing mussel beds are true. Over the past two summers, she and a handful of other observers have looked at more than 25 areas between Portland and Harpswell, surveying by foot, kayak, and small boat.

Baby mussel spat, the floating plankton phase of mussels, appear to be plentiful in the water column. Commercial aquaculture growers are getting plenty of natural seed set on their ropegrown mussels. Juvenile mussels are being found on mooring ropes, wharf pilings, and floating docks. “It’s the intertidal and subtidal horizontal mussel beds that are missing,” Ann reports.

Dr. Brian Beal, Professor of Marine Ecology at University of Maine at Machias, and others suspect that bottom-dwelling crustaceans, such as lobsters, rock crabs, green crabs, and Asian shore crabs, may feed on baby mussels trying to establish a foothold on the ocean floor. But Brian says field testing is needed to prove or disprove this hypothesis. He suggests cordoning off some bottom areas from predators with cages or nets to see if juvenile mussels survive there.

Ann has found small juvenile mussels on flats in Brunswick. “What is disturbing is that when you do find pockets of mussels, they are just individuals of one age. You don’t find whole beds of mussels, with new mussels growing on older ones, like we used to see.”

Everyone seems to have a different theory as to why the once ubiquitous blue mussels have disappeared: green crabs and other predators, dragger nets destroying mussel beds, warming sea temperatures, and ocean acidification. Cathy Ramsdell, Friends of Casco Bay Executive Director/Casco Baykeeper Pro Tem, cautions, “There are a lot of theories, but there isn’t much research being done on the change in distribution patterns of blue mussels and the possible causes. All we have is speculation. Our current objective is to try to get a handle on presence or absence of beds along the coastline of Casco Bay.”

Ann Thayer says, “This project with Friends of Casco Bay is totally driven by citizen scientists. It’s another reason why our volunteers are so important. We are looking for people with small boats who can survey the eastern part of the Bay from Brunswick to the New Meadows River.” If you are interested in joining the search, contact Friends of Casco Bay at keeper [at] cascobay [dot] org.

The Impact of Coastal Acidification—It Shucks to Be a Clam

In the summer of 2014, Friends of Casco Bay placed hatchery-reared baby clams in the mud at Recompence clam flat in Freeport, Maine, where we measured very low pH levels. Image A shows a clam prior to deployment in the mud. Image B shows a clam after just one week in the mud, where it became heavily pitted due to the high acidity of the mud. Image C is a close-up of the same clam. All of the deployed clams exhibited obvious signs of pitting.

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!

Our research on mud pH on 30 clam flats around Casco Bay suggests that the more acidic the clam flat, the less hospitable it is for clams.

Read the next section of the report Lawns Are to Blame for Much of the Nitrogen and Toxic Chemicals in the Bay