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What are invasive species?

Invasive species are plants, animals or micro-organisms that have been introduced to an area outside of their native range, usually catching the native species by surprise and therefore they pose a threat to the natural ecosystem. These species are most often introduced by humans, either by accident or released on purpose without consideration of the consequences. Once the invasive species are established in a new area, they persist on their own, but the situation can be worsened when humans continue to unknowingly aid in the spread.

Invasive Species Within the Watershed

While exploring outdoors within the watershed, you may have seen the species listed below and perhaps not known that they are invasive! Next time you spot one, make sure to snap a photo and upload it to the iNaturalist app to help us and other organizations as well as scientists understand the extent of invasive species spread within the Kennebecasis.

Below are some of the invasive species that can be found within our watershed. Click the buttons for identification tips and more!


Some of these buttons
don't work just yet - we
are working on adding
a section for each species!

Potential Threats to the Watershed

There are invasive species which have been introduced to New Brunswick but have yet to invade the Kennebecasis Watershed. Listed below are some of those species which have not been identified yet but regardless are important to watch out for - invasive species removal or management is much easier if action is taken right away, before the species establish.


What is the KWRC doing to help?

Here at the KWRC we are working hard to develop our understanding of invasive species so that we can better educate our community and protect our watershed. We are doing our best to spread awareness on how to curb further spread of invasive species as well as prevent new invasive species from invading.

Some of our current projects include:

  • Developing a map of invasive species locations across the Kennebecasis watershed

  • Developing a communication plan for increased invasive species awareness

  • Determining the risk that Eurasian Watermilfoil (EWM) has on native sturgeon species

  • Deploying early-detection Emerald Ash Borer (EAB) traps

We are working with the New Brunswick Invasive Species Council (NBISC) to detect and monitor new and existing species in our watershed. The KWRC will continue to aid the NBISC with further research efforts. We have received funding from the Department of Fisheries and Oceans to conduct research on the interactions of some invasive species within the lower regions of our watershed. In the future, we would like to establish management plans for lessening the impact of invasive species, hoping to eventually remove their presence over time.

What can YOU do to help?

There are many different activities that you can participate in (or avoid!) to help prevent and monitor the spread of invasive species. Educate yourself on how to identify the different invasive species in our watershed and share this knowledge with others. This knowledge helps protect the environment as well as yourself - did you know that some invasive species have toxins that can cause dermatitis?

Report invasive species on iNaturalist; contributing to citizen science helps small organizations like the KWRC gather more reliable information. Using iNaturalist is easy: download the free app, upload a few photos of your finding along with the location found, and then we can see your identification and add that as a point on our invasive species map!

Preventing the spread is the most important means of management!
Help lessen the spread with the following tips:

  • Do not transport firewood

  • Do not dump live bait or fish from aquariums into any waterbodies

  • Clean your outdoor equipment after use: hiking shoes, off-roading vehicles, boat, etc.

    • Programs such as Clean, Drain, Dry and Play, Clean, Go promote these methods!​

  • Check your pets' fur for hitchhikers like seaweed fragments or seeds

  • Be cautious when navigating through invasive species (they could hurt you!)

  • Promote native plant species in your own garden! 


Other Resources

Eurasian Watermilfoil

Myriophyllum spicatum

Anchor 1


Eurasian watermilfoil (EWM) is an invasive plant that is native to Asia, Europe and Northern Africa. Since its introduction to Canada in 1961, it has become one of the most widespread invasive aquatic plants on the continent. It is found in all the Great Lakes, the St. Lawrence River, and is now in the Kennebecasis River.


This plant is spread easily from boats and other recreational activities, as broken plant fragments readily root and infest new areas.

Eurasian water-milfoil spends its life submerged in water. It is identified by its feather-like leaves that arrange in whorls around the plant stem.

In July and August, small red flowers are visible just above the water’s surface.

Environmental Impacts

The impact of Eurasian water-milfoil on our waterways can be severe. It is an extremely competitive species that causes a reduction in biodiversity as it crowds out native species and suffocates fish by lowering oxygen levels. The thick mats of milfoil also hinder beloved recreational activities such as swimming and boating - and dense stands lead to water stagnation which means more mosquitoes!

What You Can Do:

Clean Drain Dry Program

The New Brunswick Invasive Species Council and the KWRC recommend cleaning all recreational equipment after use, draining the water on land, and drying the equipment. By taking the time to follow these 3 simple steps, you are actively preventing the spread of invasive species in our watershed and thus advocating for the health of native species!


Eurasian Watermilfoil Hot-Spots

EWM found
EWM found in abundance

Japanese Knotweed

Fallopia japonica

Anchor 2


Japanese Knotweed is an invasive semi-woody plant that is native to Eastern Asia and was introduced through the horticultural trade, planted in gardens or yards ornamentally.


It was also used to aid in erosion control due to its rhizomic root system, but has since spread across Canada and the United States, crowding out native species. It is incredibly persistent and can spread nearly 10m from its parent stem. Japanese Knotweed has been found along streambanks in our watershed and within residential areas.

Environmental Impacts

Japanese Knotweed spreads quickly creating dense thickets that outcompete native trees and shrubs, therefore degrading wildlife habitats and healthy biodiversity. Even the dense layers of decomposing leaves and stems from these plants prevents any establishment of native plants. The root systems of Japanese Knotweed are very aggressive and strong, they can crack concrete and asphalt. Therefore this invasive plant is very disruptive in residential areas and difficult to remove; once established, it consumes a lot of time and money to remove even a small patch.

What You Can Do:

Like with most invasive species, it is easier to prevent its spread than to remove it once it has established. This means that being able to identify Japanese Knotweed is an important factor in preventing the spread, because you can avoid infested areas, avoid allowing growth in your garden or neighbourbood, and report any sightings on the iNaturalist app.

  • Posting any sighting of this plant to iNaturalist allows organizations to see the extent of an invasion and helps in the development of management and/or removal plans

  • If you see Japanese Knotweed being sold at garden or landscaping businesses, please report it to the New Brunswick Invasive Species Council

  • Avoid infested areas to avoid the accidental transportation of seeds. Or, if you do encounter the plant, make sure to check your clothing and shoes as well as your pet's fur for seeds or fragments

  • If you're attempting to remove Japanese Knotweed from your property, reach out for advice in creating a removal plan to avoid new growth - even a root fragment can produce new plants. Don't dispose of the plant material (roots, flowers, seeds) in your compost - in this case it would be best to send the material to your local landfill

Woodland Angelica & Wild Parsnip

Angelica sylvestris

Pastinaca sativa

Anchor 3

Woodland Angelica flowers


Woodland Angelica and Wild Parsnip are native to Europe and Asia. Both species are biennial wildflowers which means they produce leaves in their first year and flower in their second year. These species commonly invade ditches, meadows, roadsides and landfills. Both species produce a phytotoxic sap that can cause dermatitis: when it comes into contact with the skin, it reacts with sunlight to cause painful burns. The roots of Wild Parsnip are edible, which is why it was once transported as a desirable species.

Environmental Impacts

When these species invade an area, they create dense stands which outcompete with native species, reducing biodiversity and wildlife habitats. They also create problems for humans who wish to explore because they have a harmful sap which reacts with sunlight and causes burns on the skin. They can also invade foraging crops such as hay, oats, and alfalfa, reducing the quality and salability. Not only this, but the chemical compounds in this plant have been known to reduce weight gain and fertility in livestock when they ingest Woodland Angelica or Wild Parsnip. These chemicals may also have a similar effect on wildlife who eat it, and because of their ability to outcompete native plant species, these invasive species may be the only plants available for wildlife to eat in invaded areas.


We are working hard to improve our understanding of invasive species in our watershed and as we do so, we will be adding more information to this page.

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