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Volunteers assisting in managing invasive aquatic species
Invasive Species

People have spread species from one geographic area to another throughout history, inadvertently as well as purposefully. Usually, this does not create a problem. However, there are a small percentage of species, that when removed from the insects, diseases, and competing species that control their numbers in their native area, become established, spread rapidly, displace native species, and may even change the way an ecosystem works.

These "invasive" species pose a great threat to the native biodiversity the refuge was established to protect, so refuge staff are very active in educating the public and specific target audiences about the issue, as well as working on early detection and rapid response and control projects.

The Problem
Only a small number of the thousands of species that have been either purposefully or accidentally introduced into the watershed have the potential to become, or have already become, invasive. However, when certain species are introduced from other places and find conditions favorable, they may be able to out-compete native species, especially if they have no predators adapted to control them in their new location. In fact, many of these species were introduced specifically because they were easy to establish, hardy and disease resistant. In addition to the initial introductions, human activities can favor the spread of many of these species. When a species can spread into natural communities, become established, displace native species, and cause ecological and economic damage, it is said to have become invasive. back to top

Invasive Plants
Although some birds and mammals have been introduced, fish and plants have been the most common introductions. According to Bickford and Dymon (1990), 950 of the 2,700 plants in Massachusetts have been introduced. Problems are being caused by invasive plants throughout the watershed. Although common reed (Phragmites communis) and purple loosestrife (Lythrum salicaria) degrade wetlands throughout the watershed, these two plants seem much more widespread in Connecticut, affecting a great number of wetland acres there. Another plant affecting both wetland and upland habitats in Connecticut is Japanese stilt grass (Microstegium vimineum). Oriental bittersweet (Celastrus orbiculatus), Japanese knotweed (Polygonum cuspidatum), multiflora rose (Rosa multiflora), buckthorns (Rhamnus cathartica and Rhamnus frangula), and Japanese barberry (Berberis thunbergii) are widespread in upland areas, with the knotweed extending up into New Hampshire and Vermont. Eurasian milfoil (Myriophyllum spicatum) is a problem in many ponds and lakes in the watershed. back to top

Non-indigenous Fish
Non-indigenous fish species are found throughout the length of the Connecticut River and its tributaries. There are more introduced fish species in the watershed than there are native species. Of the freshwater fish species found within the watershed, native or indigenous freshwater species account for 33 fish and nonBindigenous freshwater fish, 35. Many species were introduced in an effort to provide recreational fisheries, specifically, the trouts, basses, pikes and sunfishes. Native species populations were reduced because of exploitation, habitat loss and water quality degradation. Land management practices including forestry and dairy and truck farms, damming for industry, and industrial discharges resulted in altered habitat and water quality conditions that were better suited for nonBindigenous species. The distributions and populations of fish are better know than those of any other aquatic species. The state fishery and heritage agencies are working together to avoid the loss of native fish species as a result of the purposeful or accidental introduction of nonBnative fish and plant and animal species. back to top

Invasive Invertebrates
Asiatic clam (Corbicula fluminea) is a freshwater clam that first entered North America in the early 1900's, reaching the MidBAtlantic states in the 1970's and 1980's. The animal obtains a size of approximately oneBhalf inch as an adult. The Asiatic clam has been identified in the lower reach of the Connecticut River. It is of great concern because it has an incredible propensity to reproduce: an average of 70,000 offspring per adult per year. It is of great economic concern because of its ability to clog industrial water intake pipes. It is a serious environmental threat to the ecosystem because it will displace native mollusk species. It has the potential to greatly disrupt native fish and other aquatic animal and plant species as a result of its physical presence (10,000 to 20,000 individuals per square yard) and its impact on the food web.

Zebra mussels (Dreissena polymorpha), although not yet introduced into the Connecticut River system, could do very significant harm to native freshwater mussels. The animal obtains a size of approximately oneBhalf inch to an inch and oneBhalf as an adult. It is of great concern because similar to the Asiatic clam (above), it is has an incredible propensity to reproduce. It is also of great economic concern because of its observed ability to clog water intake pipes of waste water treatment plants, electric generation plants and industrial operations. It is a serious environmental threat to the ecosystem because it will displace native mollusk species. It has the potential to greatly disrupt native fish and other aquatic animal and plant species as a result of its physical presence and its impact on the food web. Because of the incredible populations of these animals that build up, they filter from the water vast amounts of algae, phytoplankton, and zooplankton. This eliminates or greatly reduces the food supply for other organisms. back to top

Mute Swans
Mute swans (Cygnus olor) are increasing their populations in Connecticut and cause damage to plants which provide food for other waterfowl as well as outcompeting other waterfowl for nesting habitat. back to top

Introduced Forest Pests
Introduced forest pests are also a huge problem. Gypsy moths have caused widespread damage over the years. In addition, attempts to control them severely affected non-target native species. DDT spraying for gypsy moth control in the 1950's and 1960's severely depressed the populations of many butterflies and other insects. The wooly adelgid, an introduced aphid (Adelges tsugae) is presently killing hemlock trees, often found on steep slopes near the rivers in Connecticut, posing potential erosion problems. Diseases, such as chestnut blight, Dutch elm disease, and a fungus affecting butternut trees also have major impacts on species and the makeBup of natural communities. back to top

Refuge Activities
Since invasive species pose a major threat to native species, the refuge is very active on this issue. The refuge has a full time Invasive Plant Control Initiative Coordinator who works on educational and other partnership projects full time.

National Fish and Wildlife Foundation Funds Invasive Plant Initiative in the Watershed
This spring, the National Fish and Wildlife Foundation awarded $85,000 to the National Wildlife Refuge Association (NRWA) for administering a two-year grant for invasive plant work in the Connecticut River watershed. These funds will help multiple partners at both the local and watershed scales to take strategic actions and position us well for new larger sources of funding should they become available.

This grant will enable:

  • public outreach, baseline inventory and on-the-ground invasive plant control within six localized Cooperative Invasive Species Management Area (CISMA) in the watershed (within the Headwaters, Ottauquechee, Upper White, Westfield, Upper Farmington, and Eightmile River watersheds).
  • sharing of information between CISMAs and state and regional invasive plant professionals, thus enhancing success and preventing duplication of efforts.
  • strategic planning to identify where invasive plant control is required to protect the most important natural resources.
  • the identification of emerging invasive threats by CISMA members and citizens of their communities.
  • early detection and rapid response to thwart new invaders.
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New England Invasive Plant Group
Refuge staff were instrumental in forming, and coordinating the New England Invasive Plant Group (NIPGro). This organization networks the many individuals, organizations and agencies interested in controlling invasive plants in the region and is working toward the end goal of comprehensive prevention and control to protect natural communities and native species. Over 1,700 NIPGro members receive information on invasive plant issues and control through regular newsletters, workshops and conferences (see below), as well as the IPANE website (see below). Other services such as an information clearinghouse and slide loans are offered. To join this organization (free), contact cynthia_boettner@fws.gov back to top

Invasive Plant Atlas of New England
Supported by a six-year grant from the US Department of Agriculture, three major partners in NIPGro (the University of Connecticut; the New England Wild Flower Society; and the U.S. Fish and Wildlife Service, National Wildlife Refuge System, Silvio O. Conte National Fish and Wildlife Refuge) have begun developing an early warning/rapid response system. It is based on the Invasive Plant Atlas of New England, or IPANE. The project has trained 600 volunteers to recognize a broad array of invasive plants and has deployed these volunteers to natural areas all over New England. These volunteers report the distribution, extent and environmental conditions in which they find these plants. This data is entered into an online database. Historic locations, gleaned from herbarium records, are included. The database is being used to: quantify the current extent of the problem each plant poses; detect new invaders; understand the habitat requirements of each species; ascertain patterns of spread, and model the likely "potential distribution" of various species. The website (www.ipane.org), in addition to allowing access to the atlas data, provides other resources on invasive plants of New England such as images; information about identification, biology, and distribution; and a wealth of related information. It also enables people to report new invasions. IPANE promotes, encourages and supports early detection and rapid response activities. back to top

2001 Conference: "Maximizing Our Efforts:  Sharing Invasive Species Outreach Materials and Strategies"
The conference "Maximizing Our Efforts:  Sharing Invasive Species Outreach Materials and Strategies", otherwise known as "the Share Fair," was held on March 1, 2001 at the University of Massachusetts-Amherst and attracted ninety participants. The goal of the event was the sharing of ideas and materials between agency and organization staff already involved in invasive species outreach, as well as providing resources to organizations hoping to do outreach in the future. One of the goals was to encourage the sharing of resources to prevent the duplication of efforts. A compilation of the outreach materials gathered from the participating organization is available on loan.

Formal speakers covered the topics of galvanizing public awareness on the issue, recruiting and sustaining volunteers, and developing websites. Most conferences are designed such that a few select speakers share their experience with the group. This conference gave NIPGro members the opportunity to share their own success stories with one another through a combination of informal networking time interspersed by formal presentations and the sharing of success stories.

New England Invasive Plant Summits 2003 and 2005
The New England Invasive Plant Summits were held in Framingham 2003 and 2005 that drew 300 participants each time to learn the latest on invasive plants. These conferences, funded in part by a grant from the U.S. Department of Agriculture, were organized by the joint partners of the NIPGro/IPANE grant team, with the Silvio O. Conte National Fish and Wildlife Refuge playing a key role.

Topics by invited speakers included ecological forecasting; restoration; management; and national and regional initiatives to assess risk, inventory populations, and promote early detection and rapid response efforts. Panelists discussed assessing research needs and the risks of biocontrol.

Symposia included brief accounts from numerous speakers on research results and management experiences. Species-specific presentations were given on oriental bittersweet, Norway maple, winged euonymus, pale swallow-wort, giant hogweed, garlic mustard, purple loosestrife, Brazilian water-weed and Eurasian water-milfoil, among many other species.

Evening receptions enabled participants with posters and displays to convey information about their own projects.

Many participants commented that a highlight of these conferences was meeting people from such a wide array of backgrounds and learning to see the problem from different viewpoints. Researchers, land managers, policy makers, educators, horticulturists, volunteers and grass-roots organizers shared experiences with one another and brainstormed possible collaborations.

To download abstracts from the 2003 and 2005 Summits, visit the website: www.ipane.org

Where Do I Begin?  Planning Invasive Plant Control on Large Parcels Workshops
The staff of the Silvio O. Conte National Fish and Wildlife Refuge has been offering workshops for landowners, entitled "Where Do I Begin: Planning Invasive Plant Control on Large Parcels." In 2005, a total of 99 people attended, who collectively manage a total of 691,592 acres. Attendees came from a wide geographic area, including CT, MA, RI, NH, VT and NY. In addition to many landowners, conservation commissions, land trusts, nature centers, water suppliers, and schools and colleges, many attendees were from federal and state agencies. Many of the agency personnel were looking for information to pass along to landowners that they work with, so the workshops will have a large ripple effect. In 2006 we taught another five sessions (~ 85 more people), as well as hosted several workshops on controlling certain invasives.

The workshops were held at various locations (the U.S. Fish and Wildlife Service's regional office and the refuge's visitor centers - the Great Falls Discovery Center in Turners Falls Massachusetts and the Montshire Museum in Norwich, Vermont) and on both week days and weekends to better suit the needs of the attendees. The primary activity was leading the attendees through a prioritization process that they applied to their own parcels during the course of the day. back to top

Water Chestnut Eradication Project
As a demonstration that early detection and eradication works, the NIPGro partners are working on stopping new invasions of several plants. CT DEP is stopping hydrilla in the two ponds where it has been found in Connecticut, Connecticut Audubon Society is trying to stop mile-a-minute vine at the first known site in Connecticut, the New England Wild Flower Society is eradicating Japanese stilt grass at its first few known sites in Massachusetts, the refuge is encouraging partners to think about zebra mussel prevention in the watershed, and the refuge is trying to eradicate water chestnut in the watershed.

Water chestnut is an annual, rooted aquatic plant that can completely cover the surface of water bodies, displacing native plants and making it impossible to swim, boat, or fish. Since it is an annual, it can be controlled by keeping the plant from setting seeds - which must be done faithfully every year until the seed bed is exhausted. This eradication project is multi-faceted; it involves eradicating a large seed source, and finding and controlling any site where it may have become established after being carried there by waterfowl. In the summer, the 20-acre infestation at Log Pond Cove in Holyoke, Massachusetts is controlled each year - preventing it from setting seed by machine harvesting where the water was deep enough and with herbicide in shallow areas. In addition, the refuge enlists large numbers of volunteers and cooperators, who spend many hours hand-pulling the plants to clear all the water bodies where it is known to occur in the Ct. River watershed in Connecticut, Massachusetts, and Vermont. Citizens, water department employees, and Service fisheries program staff also inspect many new water bodies each year to try to discover any new infestations. In 2006, we hand-pulled at 39 sites, and found 12 of those, (mostly those where we have pulled the longest) to be essentially clean. If you are interested in volunteering, please contact cynthia_boettner@fws.gov back to top