The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Gammarus fasciatus
(freshwater shrimp)
Native Transplant
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Gammarus fasciatus Say, 1818

Common name: freshwater shrimp

Taxonomy: available through www.itis.govITIS logo

Identification: The 1st antenna, which is typically longer than the 2nd antenna of this species, exhibits a 2–7 segmented accessory flagellum. There are no cylindrical appendages on the coxal gills. The uronites have obvious dorsal spines and the telson shows a deep cleft, almost to the joint with the body (Pennak 1978; Peckarsky et al. 1993).

Size: G. fasciatus can grow to 14 mm in length (Pennak 1978).

Native Range: G. fasciatus is native to the Mississippi drainage and the Atlantic coast of North America from the Atlantic coastal plain to North Carolina, including such drainages as the Hudson, Delaware, and Chesapeake river systems. It may be native to the Great Lakes drainage (Pennak 1978; Mills et al. 1993; Grigorovich et al. 2003).

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Nonindigenous Occurrences: G. fasciatus was first recorded from the Great Lakes around the late 1800s to early 1900s and is known to occur throughout the drainage. It is unknown whether or not it is native to the Great Lakes. It is particularly difficult to find clear information on its distribution before 1940 (Mills et al. 1993; Grigorovich et al. 2003).

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, 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 Gammarus fasciatus are found here.

StateYear of earliest observationYear of last observationTotal HUCs with observations†HUCs with observations†
Colorado200920091Roaring Fork
Michigan187420014Lake Huron; Lake Michigan; Lake Superior; St. Marys
Minnesota200120011St. Louis
Nevada194119621Havasu-Mohave Lakes
New York187418741Lake Ontario
Ohio187418741Lake Erie
Wisconsin200120011St. Louis

Table last updated 5/16/2018

† Populations may not be currently present.

Ecology: G. fasciatus is a freshwater benthic species that can tolerate some very low levels of salinity. It occurs in both rivers and lakes and is particular abundant in shallow well oxygenated areas. In the St. Lawrence River, the abundance of G. fasciatus is correlated with the biomass of Cladophora spp. and macrophytes as well as pH. In some ponds in Ontario, it occurs at pH above 7. G. fasciatus survives well at water temperatures around 10–15°C. Starting at 20°C, temperatures are less tolerable. The length of time G. fasciatus can tolerate a specific water temperature above 20°C decreases with increasing temperature. Temperatures of around 34–35°C and more cause relatively rapid mortality. G. fasciatus is frequently associated with thick macrophyte beds (Pentland 1930; Sprague 1963; Pennak 1978; Van Maren 1978; Thibault and Couture 1980, 1982; Borgmann et al. 1989; Palmer and Ricciardi 2004).            

G. fasciatus feeds on detritus and sediments, coarse and fine particulate organic matter, filamentous algae, diatoms, animal matter, its own species, and zooplankton such as Daphnia spp. Smaller individuals feed on detritus more frequently. G. fasciatus from Lake Erie exhibit better growth and survivorship feeding on faeces and pseudofaeces of introduced mussels in the genus Dreissena than those subsisting in macrophytes beds with prolific epiphytic algal growth. G. fasciatus can be a common food item for many fish species, including yellow perch (Perca flavescens) (Swiss and Johnson 1976; Borgmann et al. 1989; Weisberg and Janicki 1990; Delong et al. 1993; Brent Summers et al. 1997; Gonzalez and Burkart 2004).            
In Lake Ontario G. fasciatus is potentially one of the hosts for the nematode Cosmocephalus obvelatus, which infects the oesophagus of gulls. In the St. John estuary, New Brunswick, it is host to the nematode Capillospirura pseudoargumentosa, which develops to the infective stage in the amphipod and then infects shortnose sturgeon. The swim bladder nematode Cystidicola farionis develops to the 3rd stage in this species, and then eventually infects fish species. G. fasciatus is intermediate host to other aquatic parasites as well, including some acanthocephalans (Johnson 1975; Smith and Lankester 1979; Wong and Anderson 1982; Appy and Dadswell 1983).            

G. fasciatus can produce on the order of 20 embryos in a given clutch (Borgmann et al. 1989). See Clemens (1950) for a detailed account of the life cycle and ecology of G. fasciatus.

Means of Introduction: Unknown. If G. fasciatus is an introduced species in the Great Lakes, possible means of introduction could include transport in either solid or liquid ballast, arrival on aquatic plants, arrival with stocked fish, dispersal via canals, and/or introduction via fish bait (Mills et al. 1993; Hogg et al. 2000).

Status: Established throughout all the Great Lakes but may be native to the basin.

Impact of Introduction: Unknown

Remarks: G. fasciatus and the introduced amphipod Echinogammarus ischnus both increase in density in the presence of invasive Dreissena spp. in the St. Lawrence River, probably due to refugia and increased food resources from mussel pseudofaeces. However, in the presence of the introduced round goby, Neogobius melanostomus, the abundance of G. fasciatus has decreased in eastern Lake Erie by up to 85%. In some parts of the Detroit River, Niagara River, and Lake St. Clair, Echinogammarus ischnus is replacing Gammarus fasciatus, probably due to a stronger affinity of the former for Dreissena spp. substrate in these water bodies. In spite of this, G. fasciatus does still increase in the Great Lakes in the presence of invasive mussels through increased habitat heterogeneity and increased food from mussel pseudofaeces (Dermott et al. 1998; Stewart et al. 1998a, b; Van Overdijk et al. 2003; Barton et al. 2005; Limen et al. 2005; Palmer and Ricciardi 2005).            

There is little genetic variation between and within populations of G. fasciatus throughout the Great Lakes. There is more variability in populations found in the St. Lawrence River. This would lend evidence to the hypothesis that the Great Lakes’ populations of G. fasciatus were relatively recent introductions, possibly from systems such as the St. Lawrence, Hudson, Chesapeake, or Delaware drainages. However, it is still unclear whether or not this species is native to the Great Lakes (Hogg et al. 2000).

References: (click for full references)

Appy, R. G. and M. J. Dadswell. 1983. Transmission and development of Capillospirura pseudoargumentosa (Nematoda, Cystidicolidae). Canadian Journal of Zoology 61(4):848-859.  

Barton, D. R., R. A. Johnson, L. Campbell, J. Petruniak, and M. Patterson. 2005. Effects of round gobies (Neogobius melanostomus) on dreissenid mussels and other invertebrates in eastern Lake Erie, 2002-2004. Journal of Great Lakes Research 31(2):252-261  

Borgmann, U., K. M. Ralph, and W. P. Norwood. 1989. Toxicitiy test procedures for Hyalella azteca, and chronic toxicity of cadmium and pentachlorophenol to H. azteca, Gammarus fasciatus, and Daphnia magna. Archives of Environmental Contamination and Toxicology 18:756-764.  

Brent Summers, R., M. D. Delong, and J. H. Thorp. 1997. Ontogenetic and temporal shifts in the diet of the amphipod Gammarus fasciatus, in the Ohio River. American Midland Naturalist 137(2):329-336.  

Clemens, H. P. 1950. Life cycle and ecology of Gammarus fasciatus Say. Contributions of the Stone Laboratory, Ohio University 12:1-63.  

Delong, M. D., R. B. Summers, and J. H. Thorp. 1993. Influence of food type on the growth of a riverine amphipod, Gammarus fasciatus. Canadian Journal of Fisheries and Aquatic Sciences 50(9):1891-1896.  

Dermott, R., J. Witt, Y. M. Um, and M. Gonzalez. 1998. Distribution of the Ponto-Caspian amphipod Echinogammarus ischnus in the Great Lakes and replacement of native Gammarus fasciatus. Journal of Great Lakes Research 24(2):442-452.  

Gonzalez, M. J. and G. A. Burkart. 2004. Effects of food type, habitat, and fish predation on the relative abundance of two amphipod species, Gammarus fasciatus and Echinogammarus ischnus. Journal of Great Lakes Research 30(1):100-113.  

Grigorovich, I. A., A. V. Korniushin, D. K. Gray, I. C. Duggan, R. I. Colautti, and H. J. MacIsaac. 2003. Lake Superior: an invasion coldspot? Hydrobiologia 499:191-210.  

Hogg, I. D., Y. de Lafontaine, and J. M. Eadie. 2000. Genotypic variation among Gammarus fasciatus (Crustacea: Amphipoda) from the Great Lakes – St. Lawrence River: implications for the conservation of widespread freshwater invertebrates. Canadian Journal of Fisheries and Aquatic Sciences 57(9):1843-1852.

Holsinger, J. R. 1976. The freshwater amphipod crustaceans (Gammaridae) of North America. USEPA, Cincinnati, OH, 89 pp.

Johnson, C. A. III. 1975. Larval acanthocephalan parasites of 3 species of estuarine amphipods in North Carolina, USA. ASB Bulletin 22(2):59.  

Limen, H., C. D. A. van Overdijk, and H. J. MacIsaac. 2005. Food partitioning between the amphipods Echinogammarus ischnus, Gammarus fasciatus, and Hyalella azteca as revealed by stable isotopes. Journal of Great Lakes Research 31(1):97-104.

Mills, E.L., J.H. Leach, J.T. Carlton, and C.L. Secor. 1993. Exotic species in the Great Lakes: a history of biotic crises and anthropogenic introductions. J. Great Lakes Research. 19(1):1-54.

Palmer, M. E. and A. Ricciardi. 2004. Physical factors affecting their relative abundance of native and invasive amphipods in the St. Lawrence River. Canadian Journal of Zoology 82(12):1886-1893.  

Palmer, M. E. and A. Ricciardi. 2005. Community interactions affecting their relative abundance of native and invasive amphipods in the St. Lawrence River. Canadian Journal of Fisheries and Aquatic Sciences 62(5):1111-1118.  

Peckarsky, B. L., P. R. Fraissinet, M. A. Penton, and D. J. Conklin Jr. 1993. Freshwater Macroinvertebrates of Northeastern North America. Cornell University Press, Ithaca, New York State. 442 pp.

Pennak, R. W. 1989. Fresh-water invertebrates of the United States, 3rd ed. John Wiley & Sons, New York, 628 p.

Pentland, E. S. 1930. Controlling factors in the distribution of Gammarus. Transactions of the American Fisheries Society 60(1):89-94.  

Smith, J. D. and M. W. Lankester. 1979. Development of swim bladder nematodes 1979. Development of swim bladder nematodes Cystidicola spp. in their intermediate hosts. Canadian Journal of Zoologoy 57(9):1736-1744.  

Sprague, J. B. 1963. Resistance to four fresh water crustaceans to high temperatures and low oxygen. Journal of the Fisheries Research Board of Canada 20:387-415.  

Stewart, T. W., J. G. Miner, and R. L. Lowe. 1998a. An experimental analysis of crayfish (Orconectes rusticus) effects on a Dreissena-dominated benthic macroinvertebrate community in western Lake Erie. Canadian Journal of Fisheries and Aquatic Sciences 55(4):1043-1050.  

Stewart, T. W., J. G. Miner, and R. L. Lowe. 1998b. Quantifying mechanisms for zebra mussel effects on benthic macroinvertebrates: organic matter production and shell-generated habitat. Journal of the North American Benthological Society 17(1):81-94.  

Swiss, J. J. and M. G. Johnson. 1976. Energy dynamics of 2 benthic crustaceans in relation to diet. Journal of the Fisheries Research Board of Canada 33(11):2544-2550.  

Thibault, Y. and R. Couture. 1980. 24 hour median lethal temperature of Gammarus fasciatus (Crustacea, Amphipoda) acclimated to various temperature levels. Revue Canadienne de Biologie 39(3):149-152.  

Thibault, Y. and R. Couture. 1982. The upper thermal resistance limit of Gammarus fasciatus, Say (Crustacea, Amphipoda) and its utilization in thermal effluent situations. Canadian Journal of Zoology 60(6):1326-1338.  

Van Maren, M. J. 1978. Distribution and ecology of Gammarus tigrinus and some other amphipod Crustacea near Beaufort, North Carolina, USA. Bijdragen tot de Dierkunde 48(1):45-56.  

Van Overdijk, C. D., I. A. Grigorovich, T. Mabee, W. J. Ray, J. J. Ciborowski, and H. J. MacIsaac. 2003. Microhabitat selection by the invasive amphipod Echinogammarus ischnus and native Gammarus fasciatus in laboratory experiments and in Lake Erie. Freshwater Biology 48(4):567-578.  

Weisburg, S. B. and A. J. Janicki. 1990. Summer feeding patterns of white perch, channel catfish, and yellow perch in the Susquehanna River, Maryland. Journal of Freshwater Ecology 5(4):391-405.  

Wong, P. L. and R. C. Anderson. 1982. The transmission and development of Cosmocephalus obvelatus (Nematoda: Acuardioidea) of gulls (Laridae). Canadian Journal of Zoology 60(6):1426-1440.

Author: Kipp, R.M.

Revision Date: 5/2/2018

Citation Information:
Kipp, R.M., 2018, Gammarus fasciatus Say, 1818: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=26, Revision Date: 5/2/2018, Access Date: 5/23/2018

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.

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Citation information: U.S. Geological Survey. [2018]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [5/23/2018].

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