Keeping the Shuswap free of invasive mussels

The Shuswap is at risk of being invaded by aquatic invasive mussels. It sounds like a science fiction flick, doesn’t it? It’s not – it’s a very real threat, and we all need to do our part to prevent it. 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!

• What you need to do
• What are Zebra and Quagga Mussels?
• The impacts and costs of an invasion
• What do boaters, paddlers and fishers have to do with it?
• Monitoring the Shuswap for Zebra and Quagga Mussels
• Reporting invasive species

What you need to do

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

It’s critically important that we stop the spread of aquatic invasive mussels. Anyone moving a watercraft of any kind into British Columbia is required to stop at watercraft inspection stations.

Staff will inspect and decontaminate your watercraft, free of charge. Stopping is required by law, and failing to stop could cost a traveller a hefty fine.

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

Within BC, you must also clean, drain and dry watercraft and gear before moving to another lake or river. This helps prevent the transmission of other invasive species, such as Eurasian water milfoil and whirling disease.

Thank you for your cooperation to keep BC waters free of invasive Zebra and Quagga Mussels.

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 1980’s on ships coming from Europe, where the mussels originate. Since then, they have established in many lakes and rivers in Eastern and central North America, and as far west as California.

Zebra and quagga mussels are 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 dock piling, boat hull, chain or pipe.

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, Idaho 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 hard 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. See larger view.

The impacts and costs of an invasion

Zebra and quagga mussels would create enormous problems for the Shuswap because they cling to, colonize and encrust hard surfaces underwater: boats, pilings, water supply and irrigation systems, docks — you name it. Additionally, they litter beaches with their small razor-sharp shells, they produce foul odours and they pollute water quality, putting the lake ecosystem and drinking water at risk. They can substantially alter aquatic food webs, which could contribute to the collapse of important native fish populations such as Pacific salmon.

The cost to property owners, tax-payers and rate-payers for dealing with these impacts in BC is conservatively estimated to be $43M per year.

This boat spends its time in mussel-infested waters. Consequently, adult mussels have colonized on the hull. Photo: Columbia Shuswap Invasive Species Society

What do boaters, paddlers and fishers 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.

 SWC's Bringing a Watercraft to BC poster. See larger view.

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.

Prevention is key. Don’t move a mussel! Clean, drain and dry your watercraft and gear, and stop at watercraft inspection stations.

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

The Shuswap Watershed Council supports the Columbia Shuswap Invasive Species Society (CSISS) as they monitor the Shuswap watershed for Zebra and Quagga mussels. Monitoring is important for determining 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 for invasive Zebra and Quagga mussels (meaning that they have never been found in the Shuswap).

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. Additional funding from the Shuswap Watershed Council allows CSISS to expand the monitoring program in the Shuswap to include extra monitoring sites, and more frequent monitoring.

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.

Reporting invasive species

Suspected sightings of zebra and quagga mussels – or other aquatic invasive species, such as Asian 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.