Prevent the Spread of Invasive Mussels to British Columbia

Invasive zebra and quagga mussels pose a very serious threat to the lake environment, drinking water, tourism and the economy. Whether you’re a resident or a visitor to the Shuswap, whether you’re a boater, paddler or fisher — you need to be part of the prevention!

ON THIS PAGE

• What you need to do
• What are zebra and quagga mussels?
• The impacts and costs of an invasion
• Monitoring the Shuswap for zebra and quagga mussels
• Report invasive species

What you need to do

You are required to stop at watercraft inspection stations that are on your travel route into and around British Columbia

It’s critically important that we prevent the spread of invasive zebra and quagga mussels. Anyone moving a boat or watercraft of any kind into and around British Columbia is required to stop at watercraft inspection stations on their travel route.

Watercraft inspection stations are set up along highways at entry-points to BC and are staffed by the BC Conservation Officer Service. When you travel with a watercraft, stopping at inspection stations is required by law. Failing to stop can result in a $345 fine. Staff will inspect and, if necessary, decontaminate your watercraft (free of charge).

If you’ve arrived in the Shuswap from outside of BC and did not stop at an inspection station, please phone the provincial hotline 1-877-952-7277 before you launch your watercraft.

You can learn more about watercraft inspection and bringing a boat to BC by visiting the BC government website.

Travellers with watercraft of any kind are required to stop at watercraft inspection stations. Photo: East Kootenay News

Additionally, all watercraft users should practice clean-drain-dry, a three-step process to help eliminate invasive species from watercraft:

• Clean: After removing a watercraft from the water, clean it to remove mud, plant material, small aquatic life and other debris
• Drain: Drain all compartments onto dry land
• Dry: Ensure your boat or watercraft is thoroughly dried before relaunching.

Clean-drain-dry helps prevent the movement of other invasive species such as Eurasian water milfoil and whirling disease.

What do boaters and watercraft have to do with it?

One of the most common ways that zebra and quagga mussels move from one waterbody to another is on watercraft and fishing gear, which can become contaminated with mussels if they’ve been used in a lake or river where the mussels are present.

Adult mussels can attach themselves directly, and juvenile mussels float freely in trapped water. There are many places they could be: the bilge, ballast, bait bucket, anchor, hull, trailer, prop, engine coolant system – and that’s just for boats. They could also be “hiding” on kayaks, canoes, stand up paddleboards, waders or water toys. They’re not easy to spot. Fully grown adult mussels are the size of your thumbnail. Newly established adult mussels are only a millimetre or two, and juvenile mussels are smaller than a grain of sand.

What are zebra and quagga mussels?

Zebra and quagga mussels don’t belong in the Shuswap, in BC, or even in Canada. They were unintentionally brought to North America in the 1980s on ships coming from Europe, where the mussels originate. Since then, they have spread to many lakes and rivers in Eastern and central North America including Quebec, Ontario, Manitoba and as far west as California. There is no known presence of invasive mussels in British Columbia. In 2023, quagga mussels were detected in Idaho, the closest-known presence of invasive mussels.

Zebra and quagga mussels are two different species (Dreissena spp.) but similar in size and appearance:

• Their size ranges from 1 mm up to 3 cm in length (as adults)
• Their shells are propeller-shaped
• Their shells are brown or cream-coloured and may have stripes
• They often grow in clusters, attached to hard surfaces underwater such as a pipe, dock piling, boat hull and more.

Invasive zebra and quagga mussels are quite small – less than an inch – and sometimes have distinguishable stripes. Photo: Columbia Shuswap Invasive Species Society

Invasive zebra and quagga mussels often grow in clusters. This is one characteristic that makes them so destructive. Photo: Columbia Shuswap Invasive Species Society

The good news is the mussels are not known to be present in Shuswap Lake, or anywhere in BC. Nor are they established in Alberta, Saskatchewan, Washington, or Oregon. Let’s keep it that way!

By comparison, native freshwater mussels in BC:

• are much larger – greater than 1 inch (as adults)
• have oval or heart-shaped shells
• do not grow in clusters or attach to surfaces.

This is an example of a native freshwater mussel. This particular specimen was found on the shore of Little Shuswap Lake near Chase.

 Native mussels versus zebra and quagga mussels. Photo: BC Ministry of Environment and Climate Change Strategy.

The impacts and costs of an invasion

Zebra and quagga mussels will impact many of the Shuswap’s treasured assets:

• Water quality: zebra and quagga mussels pollute water quality through their filter-feeding and waste products, and can contribute to toxic algal blooms
• Beaches: as the mussels die, their small razor-sharp shells wash up on shorelines and they create foul odours as they decompose, which will ruin our enjoyment of beaches
• Lake ecology and environment: zebra and quagga mussels will out-compete native species for food and habitat, and water pollution associated with the mussels will harm birds and wildlife
• Fish populations: zebra and quagga mussels’ impacts on water quality and the lake environment will negatively impact native fish populations including Pacific salmon.

Zebra and quagga mussels colonize on surfaces underwater, and removing the colonies from infrastructure including pipes, dock pilings, and watercraft will require ongoing maintenance now estimated at a cost of up to $129 million annually for BC residents according to a 2023 economic impact report from the Province of BC. Everyone in BC will be affected by this cost which includes hydro-electric infrastructure, water supply infrastructure (e.g., municipal and domestic water), irrigation for agriculture and golf courses, maintenance for boats and marinas, loss in profits and revenues from the tourism sector, loss in residential property values, and loss in property tax revenues for governments.

Everyone will pay to manage and mitigate the impacts of invasive mussels. Time spent enjoying the lake will change to time spent cleaning colonies and shells from pipes, docks, watercraft and beaches.

There’s more. If the mussels become established in the Shuswap – and it would only take one contaminated watercraft to enable that – they are virtually impossible to get rid of. If they’re introduced to the Shuswap, they’d be here to stay. And, worse yet, they reproduce at alarmingly high rates. A few mussels could become millions in a year.

Preventing the spread of invasive mussels to BC is our best option.

These sections of pipe were pulled from Lake Mead (Nevada, USA) which is infested with quagga mussels. The pipe on the right became fully encrusted and colonized with quagga mussels after only six months. Photo: El Dorado Irrigation District.

Monitoring the Shuswap for zebra and quagga mussels

Erin Vieira (Shuswap Watershed Council) and Sue Davies (Columbia Shuswap Invasive Species Society) monitoring Shuswap Lake for invasive mussels at Blind Bay, June 2020

Early detection monitoring for invasive zebra and quagga mussels is carried out in the Shuswap watershed by the Columbia Shuswap Invasive Species Society (CSISS) with financial support from the Shuswap Watershed Council. This monitoring is important to determine if the mussels have invaded the Shuswap. For the past several years, CSISS has monitored several locations in the Shuswap watershed, multiple times throughout the spring, summer, and fall months. To date, all the water samples have had negative results, meaning that they have never been found in the Shuswap.

 By monitoring the Shuswap for invasive mussels,
essentially we are looking for something that we hope desperately not to find.

 The SWC’s and CSISS’ work is part of a larger effort across the province to monitor several lakes in British Columbia for invasive mussels. This is done according to the Provincial Invasive Mussel Field Protocol, set by the BC Ministry of Environment and Climate Change Strategy and supported by funding from the Habitat Conservation Trust Foundation and other agencies.

If invasive zebra and quagga mussels were to reach the Shuswap, we would want to know as soon as possible so that swift action can be taken. The BC Ministry of Environment and Climate Change Strategy is the lead agency responsible for responding to a new invasive species. Their Zebra and Quagga Mussel Early Detection and Rapid Response Plan for British Columbia would guide the response.

Report invasive species

Suspected sightings of zebra and quagga mussels — or other aquatic invasive species, such as Invasive clams — should be reported to the BC government using one of the following methods:

• the provincial RAPP hotline at 1-877-952-7277
• The "IAS Report Invasives" BC app
• An online reporting form, on the Government of BC website.

The IAS Reporting Invasives app is available in the Apple App Store and on Google Play.