People who live near and utilize waterways for a variety of purposes (just about everyone) can play a part in stopping the spread of aquatic invaders. In many cases, introductions can be avoided by exercising minimal care in the use and handling of living aquatic organisms. The following are a few simple guidelines that can be followed to limit the spread of these species.

Choosing Plants and Animals for Your
Home Aquarium and Water Garden
The following invasive plants may be for sale at your local pet store or nursery: Fanwort (Cabomba carolinia), South American Waterweed (Egeria densa), Hydrilla (Hydrilla verticillata), Parrot Feather (Myriophyllum aquaticum), Feathery Caulerpa (Caulerpa taxifolia). If your pet store or nursery is selling any of these species, please ask them to replace it with another that is less damaging to our environment. There are several common native species available to the trade that can make beautiful additions to an aquarium. These include Coontail ( Ceratophyllum ), Water Celery ( Vallisneria americana ) and Common Waterweed ( Elodea ). These species may not, however, be suitable for an outdoor water garden.

Outdoor water gardens are growing in popularity across New England as a centerpiece of residential landscapes. As with home aquariums, plants and fish used in water gardens are often selected because they grow well in stressful environments and require minimal care. Some of the most problematic aquatic invasive species in Massachusetts, such as purple loosestrife (Lythrum salicaria), can still be purchased in area nurseries. Because water gardens are usually outdoors and directly exposed to natural environments, the escape of imported plants is not uncommon. Seeds or other reproductive components of plants can be transported by wind or wild animals such as birds and small mammals.

Before purchasing plants or seeds for use in water gardens (or any garden for that matter) find out if the plant is native to New England or a potentially invasive import. The Massachusetts Office of Coastal Zone Management and the Massachusetts Bays Program are developing guidelines for landscapers and homeowners on selecting native plants for use around the home, including wetland species that might be selected for water gardens (look for an update in an upcoming issue of CZM's Coastlines!). In the meantime, lists of native plants can be obtained from the Massachusetts Division of Fisheries and Wildlife's Natural Heritage Program. Check with your local watershed or conservation organization to see if they have any information on appropriate plants to use around your home.

Be A Responsible Pet Owner
Learn as much as you can about the critter that you are taking home - What country is it from? What is its scientific name? What type of environment does it need in order to thrive? Not only will this information help you to better understand the needs of your pet, but it will also make you more aware of your local environment. Often, it is difficult to tell what species you are purchasing because plants and animals are generally sold under their common name. Ask your pet store, nursery, or seafood shop to provide the scientific names and countries of origin of the live plants and animals that they sell.

Instead of releasing your pet... Donate your pet to a PUBLIC PLACE: a nature museum, aquarium, school, community center, or nursing home. Give your pet to PEOPLE: your family, friends, neighbors, or other hobbyists. Contact your PET STORE for advice: some pet stores may actually allow you to return your pet.

Proper Disposal of Home Aquarium Contents
Plants and animals used in both salt and freshwater aquariums should never be disposed of in a lake, stream, pond, estuary, or even in a municipal storm drain. Like caulerpa, plants and animals sold for use in these aquariums are often very hardy and aggressive, and many freshwater invasions across the country have been attributed to the release of aquarium plants. Plants and algae can also harbor unseen snails or other small invertebrates, which might become established in local waters. All unwanted aquarium plants, algae, and fish should be placed in a plastic bag and disposed of in the trash. A few pet stores will accept unwanted aquarium plants and animals for disposal.

Proper Disposal of Unused Fishing Bait
While the sources of fish used as live bait in Massachusetts are carefully regulated, the import of invertebrate species such as worms and crustaceans are not. Worms imported from Southeast Asia, for example, may comprise a portion of the marine live bait industry in New England. Surprisingly, many species used for bait are hardy enough to be sold live in coin-operated vending machines!

While it may seem the humane thing to do, unused bait or bait packing materials should never be released into the water. Unused bait should be placed in a plastic bag or container and disposed of in the trash.

Thorough Cleaning of Boat Hulls, Engine Props, & Boat Trailers

Photo by Allson Fox

Recreational boats and their trailers are likely the most common means of transport for invasive species between water bodies within Massachusetts and New England. Aquatic plants are easily entangled in engine props, anchors, boat trailers, and fishing gear. In many cases, the transport of just a fragment of a plant to an uninfested water body can allow for the generation of a thriving and damaging population. Likewise, boat hulls provide suitable habitat for a variety of invasive fouling organisms such as the notorious European zebra mussel (Dreissena polymorpha), which has been sited in lakes only a few miles from the Massachusetts border.

Boat hulls, props, boat trailers, fishing gear, and other submerged components should be thoroughly cleaned before leaving a boat access. All animals and plant material should be disposed of in a trash receptacle as far from the water as possible. Likewise, water from bait buckets, motors, and other equipment should always be drained far from a water body. Animals, plant material, or water should never be released upon arriving at a new lake, pond, estuary, or any other water body.

Proper Disposal of Shellfish or Shellfish Waste
As with home aquarium contents, live shellfish or shellfish remnants should be kept clear of natural aquatic systems. Even shellfish harvested in Massachusetts can harbor invasive shellfish pathogens such as dermo (Perkinsus marinus) and QPX (quahog parasite unknown), which can linger in shells and other waste materials and cause significant mortality in economically important shellfish stocks. The Massachusetts Division of Marine Fisheries is also concerned about the intentional or unintentional introduction of European, Asian, and Pacific-Coast shellfish species such as the Asian clam (Corbicula fluminea) and the Pacific oyster (Crassostrea gigas). It is illegal to place any live shellfish in Massachusetts waters without a permit from the Division of Marine Fisheries, and shellfish waste should be disposed of in the trash.

Join the Search Party
You can help spot the next invader! The best way to do this is to first learn more about the native critters that share the environment with you. Then, learn about the new invaders that may be making their way towards New England. It's a lot to learn but there are folks out there that can help you, in addition to field guides, workshops, and weedwatcher teams. Bet you didn't know that most invasive species were first spotted by non-scientists, by someone out taking a walk or going for a swim. Most of these invasions were successfully stopped because they were spotted early on.

For a free field guide on marine invasive species, visit the MIT Sea Grant publications page. You can help scientists track the spread of marine invaders by joining a weed- or invader watcher team and taking part in the Marine Invader Database Initiative.

If you live near a freshwater lake or pond, you can join one of the Lake and Pond Initiative's Weedwatcher Teams. The folks with LPI will even come out to your neighborhood and teach you how to set up a Weedwatcher Team.

If you live in the Salem Sound region, you can join Salem Sound Coastwatch's Marine Invader Watchers. Using your field guide, you can join others on the hunt for new invaders.

If you live on the North Shore, you can become a volunteer with the Wetland Health Assessment Program. In addition to looking for marine invasive species, you'll work alongside scientists and learn how they measure the health of salt marshes.



Adapted from "Biological Invaders: Threats from Aquatic Invasive Species and What You Can Do to Keep Them Out of Our Waters," written for Coastlines by Jay Baker.