Ocean acidification (OA), the phrase used to describe the conditions causing the drop in the pH levels in the sea and the damaging increase in acidity that follows, is a problem identified only in the last ten years or so. But if action isn’t taken immediately, say members of a legislative commission, Maine shellfish could suffer irreparable harm.
A draft report issued in December by the Commission to Study the Effects of Coastal and Ocean Acidification warned that a broad range of shellfish are threatened, including lobster, crabs, oysters, mussels, clams, scallops, sea urchins, northern shrimp and periwinkles. About 87 percent of the value of Maine’s fisheries landings are organisms that produce shells, the report notes, and they are most impacted by more acidic waters, often making it difficult for them to form shells.
The final report will be made to the new Legislature in mid- to late-January.
The commission names the three main sources of acidification in Maine waters as: higher carbon dioxide levels in the atmosphere; the introduction of more nutrients into the ocean; and the introduction of more fresh water with its lower pH (and therefore higher acidity) levels.
The recommendations are broad, organized by a handful of goals:
“Maine must make hard decisions to effectively address the rapidly increasing rate of acidification of its marine environments,” the report asserts. “Ocean acidification and its effects are not readily observable by the general public, underscoring the importance of education and outreach efforts.”
The commission, whose members were appointed by the Legislature, include its chairmen, Sen. Chris Johnson (D-Somerville) and Rep. Mick Devin (D-Newcastle), as well as Sen. Brian Langley (R-Hancock), Rep. Wayne Parry (R-Arundel), Rep. Joan Welsh (D-Rockport), and 11 other non legislators, including Suzanne Arnold of the Island Institute (publisher of The Working Waterfront).
The group’s members unanimously supported the recommendations.
“For Maine and its commercial fisheries, addressing ocean acidification has become an urgent matter and the commission emphatically supports the immediate implementation of its recommendations,” the report states.
Since carbon dioxide in the atmosphere is considered the primary cause of OA, the report calls for both local and national efforts to reduce emissions.
Though the commission acknowledges that OA from carbon dioxide “is largely recognized as a result of global activities,” the report further asserts that “Maine can still have a discernible impact” in reducing those emissions. Several of “Maine’s state agencies are working on ways to reduce greenhouse gases,” it notes, and recommends joining those efforts “in establishing a comprehensive and unified strategy to reduce” emissions.
Maine is especially vulnerable, the commission notes.
“The Gulf of Maine is colder than most coastal areas in the United States and CO2 is more soluble in colder water,” the report states, “thereby facilitating a higher rate of CO2 uptake causing an accelerated rate of acidification.”
The commission also calls for requiring “the use of cleaner-burning fuels,” including adopting California’s low motor vehicle-emission standards.
To better mitigate and remediate OA’s impacts, the report recommends encouraging growing and harvesting kelp, rockweed and other native algae—using sustainable practices—as well as enhancing existing eelgrass beds. Such vegetation acts as a “sink” for human-produced carbon emissions, the report notes, capturing it and then removing it from the ocean when harvested.
Similarly, the commission calls for supporting shellfish production as a way of improving water quality, and for spreading shells and other forms of calcium carbonate to remediate OA in mudflats.
Under the goal of improving monitoring, the report suggests including fishing vessels and other citizen involvement, as well as relying on existing research organizations to gather more information. A database could lead to regulatory and non-regulatory ways of limiting nutrients and organic carbon from flowing into Maine ocean waters, it said.
The commission argues that its findings should be communicated to the governor, legislative leaders, the Congressional delegation, the news media and the public, with regular updates.
Developing OA curricula for K-12 schools and colleges and universities also is recommended.
“Maine’s leaders at all levels of government,” along with those who make their living from marine resources and the public, “must have a better understanding of ocean acidification, not only in terms of what is known but also in terms of the gaps in scientific data,” the report states.