2014 Invasive Plant Patrol (IPP) Survey
2014 Invasive Plant Patrol (IPP) Survey
by Judy Purdy
A sunny, calm morning in late summer, trunk scopes and diving masks, kayaks and paddles, plant checklists and aquatic plant guides, and a corps of enthusiastic, trained IPP (Invasive Plant Patrol) volunteers with life jackets. That’s all it takes to conduct the annual survey of aquatic invasive plants at Webb Lake.
The goal of Webb Lake’s IPP team is to safeguard the lake from aquatic invasive plants by annual surveys of the littoral zones so that if an invasive plant is present, it can be detected at an early stage and eliminated. The approach is akin to identifying and eliminating a disease at its earliest detection level. In general, aquatic plant surveys are limited to a lake’s littoral zones, the clear-water areas where sunlight penetrates to the lake bottom and thus aquatic plants can grow.
This summer’s survey focused on Level I areas of the lake – areas of high boat traffic where the probability of introduced species is highest, i.e., the boat launching areas at Mount Blue State Park and at Dummer’s Beach. The most thorough surveys in these Level I areas extend to water depths where native plants do not grow. Level II surveys also were conducted in lower-risk areas, such as near Camp Kawanhee and fire lanes 11, 17 – 19, and 25, areas where some IPP volunteers live.
Webb Lake surveys are scheduled for warm, windless mornings in late summer and are orchestrated by Jim Stewart, who chairs the WLA’s Environmental Committee. Jim not only organizes the annual patrols and transports all the necessary WLA-owned equipment, including the Webb Lake Association’s glass-bottom kayak (named in memory of Walter and Jane Estabrook), but also compiles all the data and submits it to the Center for Invasive Aquatic Plants, which is part of the Maine Volunteer Lake Monitoring Program.
The IPP volunteers are happy to report that no suspicious or confirmed aquatic invasive plants were found in Webb Lake this summer. In addition to Jim Stewart, this year’s surveyors included Lise Bofinger-Conant, Ron Davis, Betsy Ferguson, Nancy Maynard, Kathy Moore and her cadre of Camp Kawanhee campers and staff, Bruce and Judy Purdy, Don Smart, and Bob Withrow.
To date, five species of invasive aquatic plants have invaded other Maine lakes. They are:
• variable water milfoil
• Eurasian water milfoil
• curly-leaf pondweed and
• European naiad.
Some invasive plants grow and thrive to the point that they form thick, dense, impassable mats that choke out native plants and prevent swimming, boating, and other recreational past times. Once invasive plants, such as variable leaf milfoil, get into a lake or river, they can disrupt native habitats, decrease property values, reduce fishing and other recreational sports, and decrease water quality. And it is very costly and difficult to eliminate them and may take years to achieve.
In 1999, Maine passed legislation that outlaws invasive plants and in 2004 added laws that increase penalties. In 2010, additional legislation was passed that requires fishing competitions involving boats to conduct boat inspections.
When it comes to preventing the introduction of aquatic invasive plants, boat inspections are the primary line of defense. The two places to launch boats at Webb Lake are Mount Blue State Park boat launching ramp and Dummer’s Beach. Currently, boat inspections are performed only at the state park launching ramp. Having no boat inspections at Dummer’s Beach puts our lake at risk for invasive plants. That’s because small bits of an invasive aquatic plant, smaller than an inch, can cling to boat hulls, propellers, exhausts, paddles, even fishing tackle. Small fragments of an invasive plant can remain viable and able to grow next year, despite gear being left to dry out and freeze over the winter. A boat that has been in a contaminated body of water can inadvertently introduce enough of a plant fragment into a pristine lake that allows the harmful invasive plant to get a foothold, and subsequently grow and flourish in its new home. When this happens, one more lake or river then becomes contaminated.
The Maine Volunteer Lake Monitoring Program reported in March 2013 that 24 Maine waterways are known to be infested with invasive aquatic plant species (see mainevlmp.org for a complete list), and variable leaf milfoil is the No. 1 culprit. Infested Maine waterways include Auburn Lake, Bryant Pond, Sebago Lake, and the Ossipee and Saco rivers. Native to other parts of the U.S., but not to New England, variable leaf milfoil is an extremely hardy perennial aquatic plant and can overwinter. It is now found in all New England states except Vermont. Variable leaf milfoil spreads by fragmentation, root division, seeds, and special plant parts called turions. The main way to manage this or any other aquatic invasive plant species is:
1. Prevention by educating people about the problem and performing boat inspections;
2. Early detection using IPP surveys and quick response if any are found; and
3. Control of infestations.
According to the Maine Department of Environmental Protection’s website, “Once an invasive species takes hold, it is virtually impossible to eliminate it from a lake or stream. The cost of managing the problem, let alone the economic downside to infestations, is enormous. … Mechanical or chemical means of control can typically cost $200-2000 per lake-acre each year, with no end in sight. New research in Vermont shows that invasive plants can cost shoreline owners over $12,000 each in lost property values on infested lakes.” (http://www.maine.gov/dep/water/invasives/costs.html)
The good news, if there is any, is that so far, Maine has been spared the worst of invasive aquatic infestations. We all need to know what suspicious plants look like and keep an eye out for them. More importantly, we must be vigilant when launching boats or using equipment that has been in other lakes or rivers. If a boat, kayak, canoe, paddle, ski, life jacket, rudder, float, noodle or other water equipment has been in another lake, please do a visual inspection before putting it in Webb Lake. The smallest fragment of an invasive aquatic plant can grow into a big, unsightly, and expensive problem.
The Webb Lake IPP team’s long-term goal is to conduct an annual survey of the entire lake’s shoreline each year. If you would like to be a member of the IPP team, please contact Jim Stewart. The training is educational and free, and the surveys are fun, especially when no suspicious plants are found. And you have one more good reason just to go out and paddle or snorkel in the lake with other like-minded folks.