ZEBRA & QUAGGA MUSSELQuagga Mussel (Dreissena rostriformis bugensis) FACT SHEET Zebra Mussel (Dreissena polymorpha) ZEBRA AND QUAGGA MUSSELS These freshwater bivalves are native to the Black the Great Lakes in the late 1980s, by trans-Atlantic Sea region of Eurasia. They were first introduced to ships discharging ballast water that contained adult or larval mussels. They spread widely and as of 2019, can be found in Ontario, Quebec and Manitoba. They are now established in at least Alberta24 American or the states. north. Quagga and zebra mussels have not yet been detected in BC, Saskatchewan, IDENTIFICATION Zebra and quagga mussels—or dreissenid mussels— look very similar, but quagga mussels are slightly larger, rounder, and wider than zebra mussels. Both species range in colour from black, cream, or white with varying amounts of banding. Both mussels also possess byssal threads, strong fibers that allow the mussel to attach itself to hard surfaces—these are lacking in native freshwater mussels. There are other bivalve species found within BC (see table on reverse). waters to be distinguished from zebra and quagga IMPACTS ECOLOGICALmussels CHARACTERISTICS Ecological: Once established, invasive dreissenids are nearly impossible to fully eradicate from a water body. Habitat: Zebra and quagga mussels pose Currently, there are very limited tools available to a serious threat to the biodiversity of aquatic attempt to control or eradicate dreissenid mussels Zebra mussels can be found in the near ecosystems, competing for resources with native from natural systems without causing harm to shore area out to a depth of 110 metres, while species like phytoplankton and zooplankton, which other wildlife, including salmonids. Prevention is quagga mussels may be as deep as 130 metres. form the basis of aquatic food webs. Zebra and quagga mussels prefer depths of 2-12 the most effective solution to protecting waters metres and 10-30 metres respectively, in freshwater Removal of large masses of phytoplankton can alter from invasive mussels. lakes, rivers, reservoirs, ponds and quarries, but the water clarity, forcing light-sensitive organisms PREVENTION haveReproduction: been reported in brackish waters as well. deeper into the water body and also encourages the growth of unwanted aquatic vegetation. Dreissenid Females can produce up to one mussels selectively avoid toxic algae when feeding, off all plant parts, animals, and million eggs each year. Fertilized eggs hatch into whichEconomic: may facilitate toxic blooms. mud from boat and equipment (e.g. boots, waders, free-floating veligers (larvae) within 2-3 weeks, fishing gear). produce a calcium-based shell and then settle to Dreissenid mussels create massive colonies that can block water intakes and interfere aDispersal: hard surface. onto land all items that can hold with municipal water supplies, agricultural to always pull all the plugs! water (e.g. buckets, wells, bilge, and ballast). Ensure Dreissenid mussels may disperse irrigation and power plant operations. This naturally as a free-swimming larvae with water often results in millions of dollars per year being currents or as adults attached to other organisms, allocated to removal and management. The impact to be at least $43 million annually. all items completely before launching aquatic infrastructure or boats. of invasive mussels to BC if introduced is projected shipping, recreational boating, water in live wells, into another body of water. Human-mediated dispersal includes commercial Social: Remember, this goes for all types of watercraft and Dreissenid mussel colonies can take over gear—canoes, kayaks, paddle boards, paddles/ bait bucket or bilges and equipment such as work Rule of thumb: if it touches water it needs to beaches, leaving the shoreline covered in razor oars, life jackets, etc.—not just motorized boats! be cleaned. barges and dredges. The primary transport vector sharp shells that render it unusable for recreational within North America is recreational boating. 30 days out of water . purposes, and in turn affect property values and Depending on the temperature and humidity, boattourism. engines They by can clogging also affectwater intakes.boaters as they Learn more at CleanDrainDry.ca dreissenids can survive up to colonize exposed boat surfaces and often damage SHELL DISTINGUISHING SPECIES PHOTO & LENGTH* SHELLCHARACTERISTICS DISTINGUISHINGFEATURES Byssal Threads Lacks Ridge Byssal Threads Lacks Ridge SPECIESZebra Mussel PHOTO & LENGTH* CHARACTERISTICS FEATURES ZebraDreissena Mussel polymorpha 1 I 1 Dreissena polymorpha D-shaped, variable Bysall threads, straight I NP D-shaped,dark and lightvariable Bysallmid ventral threads, line, straight NP darkbanding and light midbilaterally ventral symmetrical line, ≤3.5 cm 1 D. rostriformis bugensis banding bilaterally symmetrical I ≤3.5 cm 1 Asymmetrical mid-ventral line D.Quagga rostriformis Mussel bugensis D-shaped, may Bysall threads, I NP Asymmetrical mid-ventral line Quagga Mussel D-shaped,have banding may Bysallventralasymmetrical threads, line with QUAGGA MUSSEL NP haveranging banding from black, ventralasymmetricalwithout line a straight with mid QUAGGA MUSSEL Amy Benson, USGS, Bugwood.org Rocky Mountain ≤4 cm rangingcream to from white black, without a straight mid Amy Benson, USGS, Bugwood.org 2 Rocky Mountain ≤4 cm cream to white Gonidea angulata 2 bluish-green LEGAL STATUS IN BC Trapezoidal, LEGAL STATUS IN BC GonideaRidgedN P angulata Mussel bluish-green No bysall threads, only Trapezoidal, RidgedN P Mussel growth rings Nofound bysall in thethreads, only shell with defined growth rings foundOkanagan in the Basin shell with defined Under provincial Prohibited regulations, Species ≤12 cm 3 Okanagan Basin Under provincial regulations, Corbicula fluminea 3 zebra and quagga Prohibited mussels Species (dead I ≤12 cm green to brown CorbiculaAsian Clam fluminea zebratransportor alive) and are quaggaor release. mussels (dead I P greenshellOvate, withto yellow/ brown Asian Clam transportor alive) are or release. P shellOvate,concentric with yellow/ rings No bysall threads, and are illegal to possess, breed, concentric rings Noinside bysall of threads,shell is purple and are illegal to possess, breed, Floater Mussels A. kennerlyi ≤6.5 cm 4 inside of shell is purple REPORTING IN BC Anodonta spp. A. kennerlyi 4 Floater Mussels ≤6.5 cm Elliptical, yellow to REPORTING IN BC AnodontaN P spp. For watercraft that have been Elliptical, yellow to For watercraft that have been N P operated outside of BC, AB, WA, shiny operated outside of BC, AB, WA, shinybrown, smooth & ID, OR, or WY please contact the FRESHWATER HABITAT FRESHWATER brown, smooth & ID,BC OR, Conservation or WY please Officer contact Service the FRESHWATER HABITAT FRESHWATER A. oregonensis ≤12.5 cm 5 BCR.A.P.P. Conservation Hotline 1-877-952-7277 Officer Service A. oregonensis ≤12.5 cm 5 Elliptical, light R.A.P.P.prior to Hotline entering 1-877-952-7277 BC waters. Elliptical, light prior to entering BC waters. to dark brown, No bysall threads tosmooth dark brown, and shiny No bysall threads Additionally, all watercraft must A. nuttalliana ≤12.5 cm 5 smooth and shiny Additionally,stop at open alldesignated watercraft watercraft must A. nuttalliana ≤12.5 cm 5 stopinspection at open stations designated in BC. watercraft It’s the inspectionLAW. Sightings stations of zebra in BC. or It’s quagga the Ovate, olive, yellow, LAW.mussels Sightings must beof zebrareported or quagga to the Ovate,red-brown olive, oryellow, black musselsR.A.P.P. hotline.must be reported to the red-brown or black R.A.P.P. hotline. ≤18 cm 6 Much thicker shell than Margaritifera falcata bcinvasives.ca.For more information on Clean ≤18 cm 6 Western Pearlshell Much thicker shell than For more information on Clean MargaritiferaN P falcata bcinvasives.ca.Drain Dry and local partners go to Western Pearlshell Elongated, light N P brown or black dreissenid species, no Drain Dry and local partners go to Elongated,brown to dark light brown or black dreissenidbysall threads, species, bottom no brown to dark bysallshell edgethreads, is concave bottom ≤12.5 cm Blue Mussels M. californianus 7 shell edge is concave ≤12.5 cm BlueMytilus Mussels spp. M.N californianus 7 REFERENCES/LINKS MytilusP spp. N bluish black to REFERENCES/LINKS P bluishWedge-shaped, black to Wedge-shaped, Ministry of Environment. Mussel Defense Program. https:// Ministrywww2.gov.bc.ca/gov/content/invasive-mussels/invasive- of Environment. Mussel Defense Program. https:// brown, ridged mussel-defence-program. Accessed 2018, August, 28. M. trossulus 7 www2.gov.bc.ca/gov/content/invasive-mussels/invasive- ≤25 cm brown, ridged mussel-defence-programTherriault et al. 2012. Risk. Accessed Assessment 2018, for August, Three Dreissenid 28. M.N trossulus 7 ≤25 cm TherriaultMussels (Dreissenaet al. 2012. Riskpolymorpha, Assessment Dreissena for Three rostriformis Dreissenid bugensis, and Mytilopsis leucophaeata) in Canadian N Mussels (Dreissena polymorpha, Dreissena rostriformis bugensis,Freshwater and Ecosystems Mytilopsis leucophaeata)http://www.dfo-mpo.gc.ca/ in Canadian Freshwaterlibrary/348700.pdf Ecosystems http://www.dfo-mpo.gc.ca/ M. edulis library/348700.pdfWestern, Oregon and Winged Floaters Anodonta spp. https:// I ≤10 cm 7 www2.gov.bc.ca/assets/gov/environment/natural-resource- M. edulis Western, Oregon and Winged Floaters Anodonta spp. https:// I ≤10 cm 7 Bysall threads www2.gov.bc.ca/assets/gov/environment/natural-resource-stewardship/best-management-practices/okanagan/ anodonta_spp.pdf