Dreissena bugensis Andrusov, 1897

Common Name: Quagga mussel

Synonyms and Other Names:

Dreissena rostriformis bugensis is viewed as a freshwater subspecies (or race) of D. rostriformis (Therriault et al. 2004).

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Identification: Dreissena rostriformis bugensis is a small freshwater bivalve mollusk that exhibits many different morphs, though there are several diagnostic features that aid in identification. The quagga mussel has a rounded angle, or carina, between the ventral and dorsal surfaces (May and Marsden 1992). The quagga also has a convex ventral side that can sometimes be distinguished by placing shells on their ventral side: a quagga mussel will topple over, whereas a zebra mussel will not (Claudi and Mackie 1994). Overall, quaggas are rounder in shape and have a small byssal groove on the ventral side near the hinge (Claudi and Mackie 1994). Color patterns vary widely with black, cream, or white bands; a distinct quagga morph has been found that is pale or completely white in Lake Erie (Marsden et al. 1996). They usually have dark concentric rings on the shell and are paler in color near the hinge. If quaggas are viewed from the front or from the ventral side, the valves are clearly asymmetrical (Domm et al. 1993). Considerable phenotypic plasticity of all morphological characteristics is known in dreissenid species and this may be a result of environmental factors, meaning the same genotype may express different phenotypes in response to environmental conditions (Claxton et al. 1998). Due to this phenotypic plasticity, visual identification is not always an acceptable means of differentiating between quagga and zebra mussels (Kerambrun et al. 2018, Beggel et al. 2015).  Thus, different methods of genetic comparison have been developed (e.g. May and Marsden 1992; Brown and Stepien 2010; Ram et al. 2012).

Size: Reaching sizes up to 4 cm

Native Range: Dreissena rostriformis bugensis is indigenous to the Dneiper River drainage of Ukraine and Ponto-Caspian Sea. It was discovered in the Bug River in 1890 by Andrusov, who named the species in 1897 (Mills et al. 1996).

Great Lakes Nonindigenous Occurrences: Canals built in Europe have allowed range expansion of this species, and it now occurs in almost all Dneiper reservoirs in the eastern and southern regions of Ukraine and deltas of the Dnieper River tributaries (Mills et al. 1996).

The quagga mussel was first sighted in the Great Lakes in September 1989, when one was found near Port Colborne, Lake Erie, though the recognition of the quagga type as a distinct species was not until 1991 (Mills et al. 1996). In August 1991, a mussel with a different genotype was found in a random zebra mussel sample from the Erie Canal near Palmyra, New York, and after confirmation that this mussel was not a variety of Dreissena polymorpha, the new species was named "quagga mussel" after the "quagga", an extinct African relative of the zebra (May and Marsden 1992). The quagga mussel has since been found in Lake Michigan, Lake Huron, Lake Erie, Lake Ontario, Lake St. Clair, Saginaw Bay, and throughout the St. Lawrence River north to Quebec City. A 2002 survey of Lake Superior did not detect quagga mussel specimens (Grigorovich et al. 2003), but by 2005 the first quagga mussel was confirmed from Lake Superior in Duluth Superior Harbor (Grigorovich et al. 2008b). 

The first sighting of quagga mussels outside the Great Lakes basin was made in the Mississippi River between St. Louis, Missouri and Alton, Illinois in 1995 (S.J. Nichols, pers. comm.).  In January 2007, populations of quagga mussels were discovered in Lake Mead near Boulder City, Nevada (W. Baldwin, pers. comm.), and in Lake Havasu and Lake Mohave on the California/Arizona border (R. Aikens, pers. comm.). This was an extremely large leap in their range and cause for much concern to limited water supplies and endangered fishes in the southwestern US. 

Table 1. Great Lakes region nonindigenous occurrences, the earliest and latest observations in each state/province, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Dreissena bugensis are found here.

Full list of USGS occurrences

State/ProvinceFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
IL200220132Lake Michigan; Pike-Root
IN200320141Lake Michigan
MI1997201913Betsie-Platte; Boardman-Charlevoix; Brule; Carp-Pine; Cheboygan; Detroit; Fishdam-Sturgeon; Lake Erie; Lake Huron; Lake Michigan; Lake St. Clair; Muskegon; Pere Marquette-White
MN200520062Lake Superior; St. Louis
NY199120199Headwaters St. Lawrence River; Irondequoit-Ninemile; Lake Erie; Lake Ontario; Niagara River; Oak Orchard-Twelvemile; Oneida; Raisin River-St. Lawrence River; Seneca
OH199220162Ashtabula-Chagrin; Lake Erie
PA199420121Lake Erie
WI200020174Duck-Pensaukee; Lake Michigan; Lake Superior; Manitowoc-Sheboygan

Table last updated 2/27/2023

† Populations may not be currently present.

* HUCs are not listed for areas where the observation(s) cannot be approximated to a HUC (e.g. state centroids or Canadian provinces).

Ecology: Quagga mussels inhabit freshwater rivers, lakes, and reservoirs. In North American populations, they are not known to tolerate salinities greater than 5 ppt (Spidle et al. 1995). Water temperatures of 28°C begin to cause significant mortality, and 32-35°C are considered lethal for dreissenid species (Antonov and Shkorbatov 1990, as cited in Mills 1996).  The depth at which the mussels live varies depending on water temperature.  They are not generally found in lakes near shore in shallow water due to wave action.  The quagga mussel can inhabit both hard and soft substrates, including sand and mud, down to depths of 130 m and possibly deeper. The maximum density of quagga mussels in Lake Michigan is at 31-90 m (Rowe et al. 2015a).

Means of Introduction: The introduction of D. r. bugensis into the Great Lakes appears to be the result of ballast water discharge from transoceanic ships that were carrying veligers, juveniles, or adult mussels. The genus Dreissena is highly polymorphic and prolific, with high potential for rapid adaptation attributed to its rapid expansion and colonization (Mills et al. 1996). Still, there are other factors that can aid in the spread of this species across North American waters. Thse factors include larval drift in river systems or fishing and boating activities that allow for overland transport or movement between water basins.

Status: The quagga mussel may have arrived more recently than the zebra based on differences in size classes of initially discovered populations, and therefore it seems plausible that the quagga is still in the process of expanding its nonindigenous range (May and Marsden 1992, MacIsaac 1994). In the 1990s, the absence of quagga mussels from areas where zebra mussels were present may have been related to the timing and location of introduction rather than physiological tolerances (MacIsaac 1994). The quagga mussel is now well established in the lower Great Lakes and found in a few harbor and nearshore areas of ake Superior. 

Quagga mussels have displaced zebra mussels in all offshore areas of Lakes Michigan (Nalepa et al 2014); Rowe et al. 2015a), Huron (Nalepa et al. 2018), and Ontario (Wilson et al. 2006; Birkett et al. 2015). There is a gradient of dreissenid domination in Lake Erie, with quagga mussels dominating eastern basins and the two species coexisting in the western basin (Patterson et al. 2005; Karatayev et al. 2014). A similar gradient was initially observed in southern Lake Ontario with quagga mussel dominating the west and zebra dominating the east (Mills et al. 1999), but the quagga mussel has since displaced zebra mussels in all offshore regions of Lake Ontario (Birkett et al. 2015). Coexistence is generally only found in shallow, productive systems such as Green Bay in Lake Michigan, Saginaw Bay in Lake Huron, and Western Lake Erie.There are multiple mechanisms by which quagga mussels displace zebra mussels, including differences in growth, reproduction, respiration, and development (Ram et al. 2012; Karateyev et al. 2015). Though zebra mussels have garnered the majority of public and research attention, quagga mussels have a more extensive distribution in the Great Lakes and their abundance far exceeds that of the zebra mussel peak (e.g., southern Lake Michigan, Nalepa et al. 2010).

Great Lakes Impacts:

Dreissena rostriformis bugensis has a high environmental impact in the Great Lakes.

The quagga mussel is a filter-feeder and at high abundances removes substantial amounts of phytoplankton and suspended particulates from the water. As such, the mechanism of its impacts is similar to that of the zebra mussel.  However, the magnitude is greater than for zebra mussels in deep lakes by virtue of more extensive distributions in deeper depth zones and higher abundances (Karateyev et al. 2015).

Extensive multi-seasonal changes have been documented in the southern basin of Lake Michigan following the proliferation of quagga mussels. The fraction of water column cleared (FC) was measured experimentally for quagga mussels in 2007–2008 and determined to exceed the phytoplankton growth rate at depths of 30–50 m, likely by a factor of five (Vanderploeg et al. 2010). This excessive filtration is hypothesized to cause a mid-depth sink of carbon and phosphorous; this is similar to the nearshore phosphorus shunt caused by zebra mussels, except that it occurs at mid-depth levels where quagga mussel densities are high (Vanderploeg et al. 2010). In support of this theory, total phosphorus (TP) and mean chlorophyll a concentrations both markedly fell in spring seasons after the expansion of quagga mussels, and TP levels remained low into summer (Mida et al. 2010). Meanwhile, silica and nitrate concentrations have significantly increased during spring and summer seasons post-expansion (Mida et al. 2010). Increased silica is likely a result of decreased uptake by diatoms, which are being filtered out of the water by the mussels. Evidence for this phenomenon was documented, particularly in the spring isothermal period when mixing occurred throughout the water column (typically before July). From 1983–2008, average spring silica concentrations in open water increased in Lake Michigan and increased slightly in Lake Huron, while summer silica concentrations experienced significant increases in both lakes. Dramatic increases in summer silica were initiated in the early 2000s in Lake Huron and in 2004 in Lake Michigan and seem to be associated with the expansion of quagga mussel populations in the lakes at those times (Evans et al. 2011). Spring phytoplankton biomass and primary production, which can be primarily attributed to diatoms, decreased 87% and 70%, respectively, in Lake Michigan from 1995–98 to 2007–08 (Fahnenstiel et al. 2010a). While diatoms previously accounted for >50% of phytoplankton composition at the deep chlorophyll layer, they composed less than 5% of it in 2007–08 (Fahnenstiel et al. 2010a).  Further, the phyoplankton community in southern Lake Michigan has shifted towards being dominated by pico- and nanoplankton (Carrick et al. 2015).

There is also evidence that quagga mussels can and have had an impact during the late winter season. Parts of Lake Michigan, Lake Huron, and Lake Erie are known to have a late winter phytoplankton bloom that is likely important for spring fish recruitment and over-wintering zooplankton species. In the Southern basin of Lake Michigan from 2001 to 2008, chlorophyll a concentrations fell from 1.1–2.6 μg/L to 0.4–1.5 μg/L in the late winter, and percent light transmission, which ranged from 74–85% at deepwater sites in 2001, increased to 94–96% in 2008 (Kerfoot et al. 2010). Likely correlated to these changes, there was also a reported decline in cyclopoid and omnivorous calanoid copepods over this period (Kerfoot et al. 2010).

Conditions in Lake Michigan, especially in the critical late winter to spring season, indicate that the southern basin is transforming into a more oligotrophic condition, similar to that of Lake Superior in terms of levels of nutrients, chlorophyll, and primary production (Mida et al. 2010). These changes are very likely attributable to quagga mussels, especially since the most significant changes happened post-2005 (consistent with large-scale quagga mussel establishment) and impacts are most pronounced during the isothermal spring and winter seasons—the seasons in which the water is vertically well-mixed, and bottom-dwelling quagga mussels have access to particulate matter throughout most of the water column (Rowe et al. 2015b; Pilcher et al. 2017).

Quagga mussels likely decrease food availability for zooplankton through their filtration of phytoplankton, thereby altering the food web. Since the early 2000s, crustacean zooplankton densities have declined in Lake Michigan (Vanderploeg et al. 2012), Lake Ontario (Bowen et al. 2018), and Lake Huron (Barbiero et al. 2009).  Concurrently, dreissena veligers in Lake Ontario have increased, and are now a substantial component of the zooplankton community (Bowen et al. 2018).  Very little research has been done, however, on the contribution of dreissena veligers to the food web.

Populations of Diporeia spp., a native amphipod that once dominated benthic habitats, have decreased dramatically since dreissenids were first introduced in the 1990s. Diporeia is an important prey item linking the benthos to higher trophic levels, and it has been suggested that the shift from Diporeia to Dreissena has transformed the benthic community into an energy sink which may diminish support of the upper food web (Nalepa et al. 2009). Diporeia populations at 30–90 m depths declined by 99% in Lake Michigan between 1994/1995 and 2010, by 97% in Lake Huron between 2000 and 2012, and by >99% in Lake Ontario between 1994 and 2008 (Nalepa et al. 2007, 2009, 2014, and 2018, Watkins et al. 2007, Birkett et al. 2015). In agreement with these findings was a 13 yr annual benthic survey (1997–2009) initiated by the EPA, which also found significantly reduced populations of Diporeia in Lakes Huron, Michigan, and Ontario (Barbiero et al. 2011). These declines were coincident with the expansion of D. polymorpha and perhaps even more so with the following expansion of D. bugensis, and have progressed from shallow to deeper waters over time (Barbiero et al. 2011, Nalepa et al. 2007, 2009, 2014, and 2018, Watkins et al. 2007). While exact mechanisms for the negative response of Diporeia to zebra and quagga mussels are uncertain, declines may be a result of a reduction in diatom abundance, a food source of Diporeia spp., or to potential toxins and pathogens associated with dreissenids and their waste products (Cave and Strychar 2015; Fahnenstiel et al. 2010a, McKenna et al. 2017, Nalepa et al. 2006, Watkins et al. 2007).

The metabolic activity of dreissenid mussels has complex impacts on water chemistry and nutrient flows (Burks et al. 2002, Bykova et al. 2006, Conroy et al. 2005, Makarewicz et al. 2000). High water filtration rates and high dreissenid abundances have lead to the accumulation of biodeposits such as feces and pseudofeces (Claxton et al. 1998). Through nitrogen (N) and phosphorus (P) remineralization, the production of biodeposits may increase and redirect nutrient supply and turnover in colonized areas (Conroy et al. 2005, Hecky et al. 2004). Some detritivorous benthic organisms may benefit from the initial redirection of nutrients to the benthos via biodeposition; however, nuisance benthic algae (e.g., Cladophora) have also historically increased with these changes (Auer et al. 2010, Hecky et al. 2004). Furthermore, when high-density dreissenid colonies form, nitrate (NO3-) concentrations may significantly increase in the interstitial water at the colony base while dissolved oxygen concentrations drop, creating potentially detrimental conditions for some benthic organisms (Burks et al. 2002). Burks et al. (2002) found that nitrate concentrations in interstitial water drawn from mussel colonies in Lake Michigan were 162% greater than Lake Michigan water column above the colonies. Concurrently, dreissenid metabolic activity may lower the N:P ratio in the water column, which (along with selective feeding behavior of dreissenids) appears to favor the growth of toxic cyanobacteria (Microcystis spp.) (Bykova et al. 2006). Additionally, quagga mussels accumulate organic pollutants within their tissues to levels more than 300,000 times greater than concentrations in the environment, and these pollutants are also found in their pseudofeces (Snyder et al. 1997). Pollutants can thus be passed up the food chain, increasing wildlife exposure to organic pollutants, such as PCBs and hexachlorobenzine, and potentially mercury (Mueting and Gerstenberger 2010, Richman and Somers 2010, Snyder et al. 1997).

Increasing amounts of biodeposits could also have an impact on multiple trophic levels via changes to the physical environment. A study in Brocton Shoal, Lake Erie, suggests that colonization of lakebed areas by dreissenid mussels and the consequent filling of remaining interstitial spaces with pseudofeces and fine-grained sediments may significantly eliminate valuable habitat for native fish (Gorman et al. 2011). Brocton Shoal, once thought to be an important area for lake trout spawning, appears to have diminished suitability as a spawning ground, potentially due to such impacts (Gorman et al. 2011).

Many of the long-term impacts of Dreissena are unclear due to the limited time scale of North American colonization. Nonetheless, it is clear that the genus Dreissena is highly polymorphic and has a high potential for rapid adaptation to extreme environmental conditions by the evolution of allelic frequencies and combinations, possibly leading to significant long-term impacts on North American waters (Mills et al. 1996). In Eurasia, it was documented that D. bugensis often replaced D. polymorpha as the dominant mussel species over time, possibly due to greater adaptability to different temperatures, levels of water mineralization, or habitat types (Zhulidov 2010). This evidence, along with recent reports of dreissenid populations in the Great Lakes, indicates that quagga mussels may dominate U.S. waters in the long-term as well. Dreissena rostriformis bugensis also inhabits a wider range of water depths, and has been found at depths up to 175 m in the Great Lakes (Nalepa et al. 2014).

Much of the work on quagga mussel impacts has focused on Lake Michigan, which has a thorough record of conditions pre- and post-quagga mussel establishment (Fahnenstiel et al. 2010b). It is quite likely that the quagga mussel has had and may continue to have effects similar to zebra mussels in other regions of the Great Lakes, as well as in the western U.S., where it has already established in Lake Mead and the Colorado River Basin (Nalepa 2010).

Dreissena rostriformis bugensis has a high socio-economic impact in the Great Lakes.

Although D. r. bugensis lacks the keeled shape that allows D. polymorpha to attach so tenaciously to hard substrata, it is able to colonize both hard and soft benthic habitats (Mills et al. 1996). Dreissena species’ ability to rapidly colonize hard surfaces causes serious economic problems. These major biofouling organisms can clog water intake structures, such as pipes and screens, thereby reducing pumping capabilities for power and water treatment plants and financially impacting industries, companies, and communities (Connelly et al. 2007). Recreation-based industries and activities have also been impacted; docks, breakwalls, buoys, and boats have all been heavily colonized and beaches have been incidentally littered with dead shells. The full extent of negative impacts on industries and recreation due to quagga mussels is as of yet unclear.

The quagga mussel has the potential to cause major costs for dams and the hydropower industry, particularly if its westward expansion continues. Colonization has already occurred at the Hoover, Imperial, Davis, and Parker Dams on the Lower Colorado River, causing various degrees of clogging and subsequent expense (Claudi and Prescott 2007a, 2007b).

The reemergence of nuisance algal species Cladophora in Lake Ontario, Lake Erie, and Lake Michigan has been largely attributed to the resulting changes in nutrient cycling and water clarity due to zebra mussels (Auer et al. 2010, Hecky et al. 2004). Similar observed effects between zebra and quagga mussel filtration suggest that quagga mussels could also contribute to this impact.

There is little or no evidence to support that Dreissena rostriformis bugensis has significant beneficial effects in the Great Lakes.

Increased water clarity following dreissenid introduction is perceived as a benefit by some, especially business owners and residents on invaded water bodies (Limburg et al. 2010).

Quagga mussels have been proposed and tested for use as bio-indicators (both in the Great Lakes and Western U.S.) due to their ability to accumulate toxins and metals at much higher levels than those found in the environment, especially when small environmental levels are difficult, and yet important, to measure (Mueting and Gerstenberger 2010, Richman and Somers 2010). For instance, the National Oceanic and Atmospheric Administration’s Mussel Watch program has been monitoring contaminants in Great Lakes dreissenids since the early 1990s.

Management: Regulations (pertaining to the Great Lakes region)
Federal law (Lacey Act 1990) prohibits the possession and transportation of quagga mussels in the United States unless intended for research.

The following regulations apply to all vessels equipped with ballast water tanks that enter a United States port on the Great Lakes after operating in waters beyond the exclusive economic zone. Vessels are required to exchange ballast water beyond the exclusive zone prior to entering any Great Lakes port. Ballast exchange may also be conducted in waters that are considered a non- threat to the infestation of an aquatic nuisance species in the Great Lakes (Allowable waters stated under ANS Task Force section 1102(a)(1)). Vessels are also required to use environmentally sound ballast water management methods if deemed necessary (NANPCA 2000).

In Pennsylvania, it is unlawful to possess, introduce, import, transport, sell, purchase, offer for sale, or barter quagga mussels (58 Pa. Code § 63.46, 58 Pa. Code §§ 71.6 and 73.1). In Indiana, it is unlawful to import, possess, or release quagga mussels into public or private waters (Ind. Admin. Code tit.312,r.9-9-3(d) and (e)). In Michigan, quagga mussels are a restricted species (Mich. Comp. Laws § 324.41301) and therefore cannot be possessed unless it is to identify, eradicate, or control the species (Mich. Comp. Laws § 324.41303). In Wisconsin, it is unlawful to transport, transfer, or introduce quagga mussels (Wis. Admin. Code § NR 40.05). In Minnesota, it is unlawful to place or attempt to place a watercraft, trailer, or plant harvesting equipment that has quagga mussels attached into state water (Minn. Stat. § 84D.10). Persons leaving the state are required to drain boats and related equipment during transportation on a public road (Minn. Stat. § 84D.10 and Minn. R. 6216.0500). Violation penalties can range from a civil fine of $250-$1,000 and/or a misdemeanor (Minn. Stat. § 84D.13).  Illinois lists quagga mussels as injurious species (ILL. ADM. CODE CH. 1, § 805).

Note: Check federal, state/provincial, and local regulations for the most up-to-date information.

Given the widespread established of quagga mussels in the Great Lakes, total eradication is considered impossible with current technologies.  Control measures have been tested in some Great Lakes nearshore environments, but at very small scales and with the main goal to begin exploring feasibility. Control efforts focus primarily on protection of human infrastructure (such as water intakes) and along vectors of spread (such as boats, trailers, gear, etc).  Controlling quagga mussels to minimize effect on natural and anthropologic systems is expensive, regardless of the method(s) chosen. Microencapsulated "BioBullets" are being developed in the UK as a more efficient method to deliver control agents to mussels (Costa et al. 2011), but these are not yet tested for open water applications or approved by the EPA.

Biological control so far has proven to be ineffective in controlling Dreissena species.  Predation by migrating diving ducks, fish species, and crayfish may reduce mussel abundance, though the effects are short-lived (Bially and MacIsaac 2000). Invasive round goby, when abundant, are effective at supressing dreissenid mussels (Lederer et al. 2008), but it should not be introduced as a biocontrol agent. Redear sunfish (Lepomis microlophus) - also nonindigenous to the Great Lakes - have been shown in experimental enclosures in Sweetwater Reservoir, CA to feed upon and control population sizes of quagga mussels (Wong et al. 2013).  Other biological controls being researched are selectively toxic microbes and parasites that may play a role in management of Dreissena populations (Molloy 1998). Laboratory testing shows strain CL145A of Pseudomonas fluorescens (a bacterium) to be highly lethal to quagga mussels; capable of eliminating over 90% of adults and 100% of larvae (Abdel-Fattah 2011, Molloy 2002).Commercially, this product is known as Zequanox® and is developed by Marrone Bio Innovations (Abdel-Fattah 2011).  Open water Zequanox® studies have been conducted on zebra mussel populations in Minnesota (Lund et al. 2018), Illinois (Whitledge et al. 2015), and Ireland (Meehan et al. 2014).

Interfering with the synchronization of spawning by adults in their release of gametes could offer control of Dreissena populations (Snyder et al. 1997). Cyanobacteria inhibited quagga mussel spawning in laboratory trials, and could potentially limit reproduction in the field if blooms occur during mussel spawning events (Boegehold et al. 2018).  Another approach would be to inhibit the planktonic veliger (larvae) from settling and attaching to a surface to begin development (Kennedy 2002).

Effective physical controls of Dreissena  include drawing down water from  public sources or a groundwater well, using infiltration intakes or sandfilter intakes (filter out veligers), thermal treatments, carbon dioxide pellet blasting, high-pressure water jet cleaning, mechanical cleaning, freezing, scraping, scrubbing, pigging, and desiccation. Potential controls include the use of benthic mats, electrical fields, pulse acoustics, low-frequency electromagnetism, ultraviolet light (UV light), and reduced pressure (USACE 2002).

A recent study has confirmed that thermal treatment of residual water in boats and other water vehicles may be a viable option for managing quagga mussel spread. Increasing temperature and exposure time was found to increase the level of veliger mortality (Craft and Myrick 2011).

Other methods of physical control include exposure and desiccation, manual scraping, high-pressure jetting (including with high temperature water), mechanical filtration, removable substrates, and sonic vibration.


Prechlorination has been the most common treatment for control of Dreissena mussels, but chlorine concentrations needed for effective control of quagga mussels may reach hazardous levels (Grime 1995). Potassium permanganate has been used as an alternative control, especially for drinking water sources.   Ozone is also a potential control.  Other toxicants (e.g., copper, niclosamide, and potash) and anti-fouling coatings may be effective; however, application of these chemicals can be detrimental to ecosystem and/or human health so possible effects should be thoroughly evaluated before use (Boelman et al. 1997, Sprecher and Getsinger 2000).

Other potential methods of quagga mussel control include oxygen deprivation, radiation, and electric currents.

For more information on Quagga mussel control in the Great Lakes region, please visit the Invasive Mussel Collaborative and the Collaborative's Dreissena Project Coordination Mapper.

Note: Check state/provincial and local regulations for the most up-to-date information regarding permits for control methods. Follow all label instructions.

Remarks: Hybridization between the two introduced dreissenid species was an initial concern. Zebra x quagga mussel hybrids were created by pooling gametes collected after exposure to serotonin in the laboratory, indicating that interspecies fertilization may be feasible (Mills et al. 1996). However, there is evidence for species-specific sperm attractants suggesting that interspecific fertilization may be rare in nature. Thus, if hybridization does occur, these hybrids will constitute a very small proportion of the dreissenid community (Mills et al. 1996). There is evidence to suggest that the apparent ability of Dreissena rostriformis bugensis to outcompete Dreissena polymorpha is due to the high mtility of the species (D'Hont et al. 2021).

Redear sunfish (Lepomis microlophus) have been shown in experimental enclosers in Sweetwater Reservoir, CA to feed upon and control population sizes of quagga mussels (Wong et al. 2013).


References: (click for full references)

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Aikens, R. 2014. – Public Information Officer, Arizona Game and Fish Department, Phoenix, Arizona. [pers. comm.]

Auer, M.T., L.M. Tomlison, S.N. Higgins, S.Y. Malkin, E.T. Howell, and H.A. Bootsma. 2010. Great Lakes Cladophora in the 21st century: same algae—different ecosystem. Journal of Great Lakes Research 36(2):248-255.

Baldwin, W. 2014. – Volunteer, National Park Service, Lake Mead National Recreational Area. [pers. comm]

Barbiero, R. P., M. Balcer, D. C. Rockwell, and M. L. Tuchman. 2009. Recent shifts in the crustacean zooplankton community of Lake Huron. Canadian Journal of Fisheries and Aquatic Sciences 66:816–828.

Barbiero, R.P., K. Schmude, B.M. Lesht, C.M. Riseng, G.J. Warren, and M.L. Tuchman. 2011. Trends in Diporeia populations across the Laurentian Great Lakes, 1997-2009. Journal of Great Lakes Research 37:9-17.

Beggel, S. Cerwenka, A.F., Brandner, J., Geist, J., 2015. Shell morphological versus genetic identification of quagga mussel (Dreissena bugensis) and zebra mussel (Dreissena polymorpha). Aquat. Invasions 10: 93–99.

Bially, A., and H.J. MacIsaac. 2000. Fouling mussels (Dreissena spp.) colonize soft sediments in Lake Erie and facilitate benthic invertebrates. Freshwater Biology 43:85-97.

Birkett, K., S. J. Lozano, and L. G. Rudstam. 2015. Long-term trends in Lake Ontario’s benthic macroinvertebrate community from 1994–2008. Aquatic Ecosystem Health & Management 18:76–88.

Boegehold, A.G., N.S. Johnson, L.L. Ram, and D.R. Kashian.  2018.  Cyanobacteria reduce quagga mussel (Dreissena rostriformis bugensis) spawning and fertilization success.  Freshwater Science 37(3)510-518.

Boelman, S.F., F.M. Neilson, E.A. Dardeau, and T. Cross, jr. 1997. Zebra Mussel (Dreissena polymorpha) Control Handbook for Facility Operators, First Edition. Miscellaneous Paper EL-97-1, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.

Bowen, K. L., A. J. Conway, and W. J. S. Currie. 2018. Could dreissenid veligers be the lost biomass of invaded lakes? Freshwater Science 37:315–329.

Brown, J. E., and C. A. Stepien. 2010. Population genetic history of the dreissenid mussel invasions: expansion patterns across North America. Biological Invasions 12:3687–3710.

Burks, R.L., N.C. Tuchman, and C.A. Call. 2002. Colonial aggregates: effects of spatial position on zebra mussel responses to vertical gradients in interstitial water quality. Journal of the North American Benthological Society 21(2):64-75.

Brown, E. – Colorado Invasive Species Coordinator, Colorado Parks and Wildlife, Denver, Colorado.

Bykova, O., A. Laursen, V. Bostan, J. Bautista, and L. McCarthy. 2006. Do zebra mussels (Dreissena polymorpha) alter lake water chemistry in a way that favours Microcystis growth? Science of the Total Environment 371:362-372.

Carrick, H. J., E. Butts, D. Daniels, M. Fehringer, C. Frazier, G. L. Fahnenstiel, S. Pothoven, and H. A. Vanderploeg. 2015. Variation in the abundance of pico, nano, and microplankton in Lake Michigan: Historic and basin-wide comparisons. Journal of Great Lakes Research 41:66–74.

Cave, C. S., and K. B. Strychar. 2015. Decline of Diporeia in Lake Michigan: Was disease associated with invasive species the primary factor? International Journal of Biology 7: 93-99.

Claudi, R., and G.L. Mackie. 1994. Practical Manual for Zebra Mussel Monitoring and Control. Chapter 1. Biology of the Zebra Mussel. Lewis Publishers, CRC Press, Boca Raton, FL. 227 pp.

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Author: Benson, A.J., Richerson, M.M., Maynard, E., Larson, J., Fusaro, A., Bogdanoff, A.K., Neilson, M.E., and Ashley Elgin

Contributing Agencies:

Revision Date: 7/19/2022

Citation for this information:
Benson, A.J., Richerson, M.M., Maynard, E., Larson, J., Fusaro, A., Bogdanoff, A.K., Neilson, M.E., and Ashley Elgin, 2023, Dreissena bugensis Andrusov, 1897: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, and NOAA Great Lakes Aquatic Nonindigenous Species Information System, Ann Arbor, MI, https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspx?Species_ID=95&Potential=N&Type=1&HUCNumber=DGreatLakes, Revision Date: 7/19/2022, Access Date: 3/24/2023

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.