• In the late summer of this year, 2020, variable water-milifoil, Myriophyllum heterophyllum, was found in Androscoggin Lake by Katherine Mahoney, a member of Androscoggin Lake’s Invasive Plant Patrol team. The suspicious plant was found in Inner Cove, at the northern end of the lake, about 400 yards northwest of the state boat launch. The plant that was found lacked the features needed to confirm an identification with 100% certainty, so the specimen was sent on to Dr. Lucas Bernacki of Saint Joseph’s College for DNA analysis. Upon learning the DNA results, which unfortunately confirmed the invasive species, a coalition of local, regional and statewide partners including 30 Mile River Watershed Association (30 MRWA), Androscoggin Lake Improvement Corporation, Lake Stewards of Maine (LSM), and Department of Environmental Protection (ME DEP), leapt into action.

On the 3rd of October, 2020, Roberta Hill of LSM and Lidie Robbins of 30 MRWA led a team of 15 volunteer invasive plant patrollers (IPPers) in screening surveys of the lake with the focus upon Inner Cove, where that first specimen was found. Several patches of variable milfoil were found; one patch, more than 10 feet in diameter, suggested that the milfoil has been present in the cove for at least a year. On October 15th, another screening was conducted, this time assisted by several of LSM’s Uber-IPPers and two divers, one from the ME DEP and one from Little Sebago’s milfoil removal team. Four additional plant clusters were identified. Invasive plants were removed from all identified locations.

M. heterophyllum spreads through two mechanisms: auto-fragmentation and vegetative propagation. The parent plant becomes more brittle toward the end of the growing season, and breaks apart (auto-fragmentation), creating numerous viable fragments. Each fragment is a clone of the parent plant and mobile. When caught in a current, or by the wind, or even something like a boat’s line they are carried off to a new location. If they come to rest in a good spot, through the action known as vegetative propagation, the fragments will sprout roots, and may establish a new colony.

The fact that (so far) the M. heterophyllum seems to be confined to the wetland at the northwestern corner of Inner Cove, provides some hope that the infestation may have been caught early on. In order to be sure, LSM, our volunteers, and partner organizations need to conduct a comprehensive (Level-3) survey of the entire littoral zone of the lake. Thanks to the efforts and dedication of the various partners and IPPers, plans are already underway to ensure such a survey will be completed next summer. If you are interested in getting involved, please contact Roberta at [email protected].

Learn more about Androscoggin Lake HERE or check out conservation areas near it HERE.

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A key reason for the Cooper surveys was to evaluate lakes for fish-stocking. They collected data on: lake depth, water temperature, dissolved oxygen, pH, phosphorus, benthic invertebrates, and plankton & fish communities. Cooper did not measure water transparency. Therefore (and unfortunately, given the ever-expanding base of Secchi data collected by LSM volunteers and others) it is not possible to explore how transparency in these lakes has changed over the 8 decades since these historical surveys were carried out.

The results of the surveys were published in a series of seven Fish Survey Reports. An interactive map showing where the lake surveys happened is HERE.

Cooper et al. used gill and seine nets to collect fish. Supplemented by information from fish & game wardens, they thus documented the structure of the fish community in each surveyed lake (species composition, diets, age/growth). By comparing these data with more contemporary data from IF&W, it is possible to examine changes in lake fish communities over the past ~ 60 years. Especially interesting is the ‘spread’ of such species as largemouth and smallmouth bass as a result of both intentional and illegal stocking (and ‘natural’ range expansion).

Explore these changes in Maine’s lake fish communities HERE.

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Also included in this undertaking are a number of regional entities, including Lakes Environmental Association, Cobbossee Watershed District, Mid-Coast Conservancy, 30-Mile River Watershed, 7 Lakes Alliance, Belgrade Lakes Association, Acton Wakefield Watershed Alliance, Allagash Wilderness Waterway, Portland Water District, Auburn Water District, Acadia National Park, and Rangeley Lakes Heritage Trust. Included are the sovereign nations of the Passamaquoddy Tribe at Indian Township, and the Penobscot Indian Houlton Band of Maliseets.

Data have also been acquired from private consultants, such as FBE and Lake & Watershed RMA, as well as others collecting lake data as part of regulatory requirements. Additional data are acquired through the DIF&W and through cooperative projects with the University of Maine System, Bates, Colby and Unity Colleges, and County Soil and Water Conservation Districts. Field data are also collected by the Maine DEP Lakes Assessment Section under probability-based studies conducted within EPA Region I, and as part of the National Lakes Assessment Study being conducted by EPA Headquarters.

We apologize if your lake data-gathering organization has been accidentally omitted. Please let us know if that is the case. Additional types of data are also submitted to the Lakes of Maine website, including Annual Loon Count data gathered by volunteers through Maine Audubon Society, and a variety of lake and watershed information provided by The Nature Conservancy.

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