Invasive Species Session at the Maine Sustainability and Water Conference

If you have any questions, please let one of the session’s co-chairs know.

Session Co-Chairs

Gary Fish, Maine State Horticulturist and State Plant Regulatory Official
Denise Blanchette, Maine Dept. of Environmental Protection

Invasive species from all taxa groups have an impact on water quality. Responses to invasive species such as emerald ash borer, hemlock woolly adelgid, hydrilla, zebra mussel and green crab are often compartmentalized. This session will focus on addressing invasive species impact and management as a whole, the strengths and challenges. Highlighting the more comprehensive approach being implemented by New York and Michigan and how other states such as Pennsylvania and Massachusetts are trying to emulate this approach.

Invaders with Benefits? Non-native Lady Beetles in Maine Potatoes

Andrei Alyokhin
School of Biology and Ecology, University of Maine

Lady beetles (Coleoptera: Coccinellidae) are an easily recognizable and charismatic family of beetles. Many lady beetle species feed on important agricultural pests; thus, for many years they have been widely used in biological control. Our studies of lady beetles in potato crops in northern Maine showed that two native species, Coccinella transversoguttata Brown and Hippodamia tredecimpunctata (Say) suffered a significant decline following the establishment of three non-native species, Coccinella septempunctata L., Harmonia axyridis (Pallas), and Propylea quatordecimpunctata (L.). Harmonia axyridis proved to be an especially aggressive competitor that can also become a nuisance pest for humans. At the same time, abundance of aphid pests of potatoes declined as non-native species became firmly established in the area, while the overall local diversity of lady beetle community increased. Arguably, invasive status of non-native species is subjective and depends on the context.

Developing eDNA Tools for Native and Invasive Aquatic Plant Detection in Maine

Sharon Mann (student)1, Roberta Hill2
1 University of Southern Maine, 7 Lakes Alliance
2 Independent Consultant

Maine’s waters are threatened by a changing climate and the spread of invasive aquatic species. Native plant communities and the complex ecological systems they support will increasingly be impacted by both of these threats. Monitoring is key to understanding and mitigating these impacts, but keeping a close eye on the health of Maine’s extensive littoral habitat is a daunting task at best; in some parts of the state it is virtually impossible using current methodologies.

This presentation will introduce attendees to a proposed project aimed at developing new genetic tools to augment (and in some cases replace) current direct visual-observation methods.

Roberta and Sharon will provide an overview of their proposed 3-year project beginning with a brief orientation to the environmental DNA (e-DNA) tools and methods that will be utilized. They will move on to share their vision of building (over time) a robust Maine-centric e-DNA library for the purpose of both facilitating the monitoring of Maine waters for the presence of invasive aquatic plants, and for tracking changes in species composition in Maine’s native plant communities in response to climate change. The talk will conclude with a discussion of the role that citizen scientists could play in the development of the new tools and methodologies.

Afternoon Break

The Challenges of Long Term Invasive Plant Management in Wetland and Riparian Environments

Andrew W. Priestley, Andrea Southworth
1 Vegetation Control Service, Inc.
2 Friends of Fort Williams Park, Cape Elizabeth Land Trust, Southern Maine Community College

Invasive plant species are prominent both within and along the borders of wetlands and riparian systems. Terrestrial species have dramatic impacts on wetlands and waterways, affecting water quality, habitat quality, species diversity or just changing the shape and or use of the land. Aggressive management efforts must not only be well thought out and responsibly and meticulously implemented, but must also be planned with a wide variety of long-term challenges in mind.

Significant long term challenges include attitudes within varying communities, current and past land uses, regulatory challenges, funding, availability of capable management professionals, effectiveness of volunteer efforts, and the volatility of the environments in the first place. Abutter and community education can make or break a management strategy and dramatically complicate implementation, particularly when considering the highly charged topic of herbicide use.

Even well-implemented control programs can fail when the effort is not sustained, and hard fought gains become tragic losses. The authors/presenters will discuss these issues from both an ecological and an implementation perspective with an emphasis on how high impact IPM methods and soft touch methods can be used to address both the immediate infestations and the various long term challenges to sustained control.

Successes and Challenges at Fort Williams Park

Andrea Southworth
Friends of Fort Williams Park, Cape Elizabeth Land Trust, Southern Maine Community College

Fort Williams Park is a 90-acre, oceanfront public park owned by the town of Cape Elizabeth, Maine. Home to Portland Head Light, the Park is a treasured space with scenic views, natural beauty, and a long military history. The Park is host to more than a million visitors per year and is a resource for communities throughout the region. It is also an important refuge for migrating birds and provides habitats for many species. Unfortunately, invasive plants have had a major impact on the Park.

The Friends of Fort Williams Park (Friends) works to improve the ecological health and sustainability of the Park. The Friends have had many successes: partnership with the town, collaboration with area nonprofits, specialists, and volunteers, and restoration of natural areas. This presentation will focus on the Friends’ comprehensive efforts to control invasive plants, add native plant diversity, and increase resources for wildlife as well as the challenges related to funding, long-term maintenance of project sites, and management roles and responsibilities.

Should Maine Develop a More Comprehensive Approach to Invasive Species Management?

Gary Fish
Maine Department of Agriculture, Conservation and Forestry

The purpose of the paper is to provide data and background on the current state of invasive species management in Maine and whether the state should consider a more comprehensive approach to manage the plethora of species causing environmental, ecological, medical and economic harms. A summary of a statewide survey is presented which indicates that Maine should consider following in the footsteps of Pennsylvania and Massachusetts and do a thorough analysis of the current invasive species programs and approaches and determine if instituting a more comprehensive approach like that used by the states of New York and Michigan can be implemented effectively in a smaller state like Maine. Most survey respondents agreed that there should be a comprehensive approach to fight invasives, along with dedicated resources and continued research. The survey also indicated that there is no uniform approach to address invasives, and the state’s efforts to control terrestrial invasives was characterized as slow and reactionary. Therefore, rapid response and control activities are needed to reduce and eliminate new and existing populations of invasive species in Maine. Cooperation and partnerships at all levels must exist to effectively prevent and manage invasive species beyond rapid response. State agencies cannot fight the battle alone. Diverse and expansive partnerships with local leadership should also be considered. Hopefully in the next decade, Maine can act to be more effective and efficient at preventing and managing invasive species.