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Nonindigenous Occurrences: This species occurs in the Volga River (Slynko et al. 2002). In the Volga River basin, it occurs in low abundances where the Uglich and Ivankova Reservoirs were impounded. It established large populations 5 years after the impoundment of the Rybinsk reservoir. This species is found in the Kuybyshev Reservoir as well. It occurs in the Upper Volga (Litvinov et al. 2009) and Danube River basin (Afanasyev et al. 2020).

Potential pathway(s) of introduction: Trans-oceanic shipping (ballast water)

It is predicted that Heterocope appendiculata will be introduced to the Great Lakes via ballast water (Wonham et al. 2005; U.S. EPA 2008). Heterocope appendiculata individuals and eggs can be taken up by the ballast of both Ballast on Board (BOB) and No Ballast on Board (NOBOB) vessels (Wonham et al. 2005). Adults produce resting stages that may be able to survive the harsh ballast tank environments. Heterocope appendiculata may be introduced to the Great Lakes via ships declaring “No Ballast on Board” (NOBOB), which are exempt from ballast water exchange. The majority of ships entering the Great Lakes are NOBOB vessels and 43% of these ships contain residual water with less than 10‰ salinity (Johengen et al. 2005). In the study, the temperature of the residual water from the vessels sampled ranged from -0.7 to 23.9°C; thus, Heterocope appendiculata is likely to survive the salinity and temperature of the NOBOB ballast water.  Heterocope appendiculata is established in the Baltic Sea basin, which contains ports in direct trade with the Great Lakes (U.S. EPA 2008; NBIC 2009).

Heterocope appendiculata does not currently occur near waters connected to the Great Lakes basin. This species is not known to hitchhike or foul recreational gear. It is not cultured, stocked, or sold in the Great Lakes region.

Heterocope appendiculata has a moderate probability of establishment if introduced to the Great Lakes (Confidence level: Moderate).

The native and introduced ranges of Heterocope appendiculata have similar climatic and abiotic conditions as the Great Lakes (Reid and Orlova 2002; Grigorovich et al. 2003; U.S. EPA 2008). Heterocope appendiculata inhabits the pelagic and littoral zone of large, deep lakes (Walseng et al. 2006; Samchyshyna 2008); there are abundant habitats suitable for this species in the Great Lakes. Heterocope appendiculata has a moderately broad physiological tolerance. This species can tolerate a somewhat wide range of water temperatures, oxygen levels, and pH. This species occurs in the Baltic Sea, which has a salinity range of 1–8 ppt (Reid and Orlova 2002). High nutrient conditions are not favorable for this species; 3 years after the fertilization of a lake, its biomass declined considerably (Langeland and Reinertsen 1982). Heterocope appendiculata overwinters as resting eggs in sub-arctic lakes (Persson and Vrede 2006) and occurs in waters that have temperatures under 5°, so it is somewhat likely that this species can overwinter in the Great Lakes. It is unlikely that climate change will impact this species’ establishment in the Great Lakes.

Heterocope appendiculata is omnivorous (Pejler 1983). It primarily feeds on protozoa, rotifers, and small crustaceans, but feeds on phytoplankton as well (Persson and Vrede 2006); these prey types are available in the Great Lakes. Little is known about the competitive abilities and fecundity of Heterocope appendiculata, but it was one of the least dominant copepods (0–1102 ind/m2) in the open water of ice fields in the Russian Arctic seas (Dvoretsky and Dvoretsky 2015).

This species has established somewhat extensively outside its native range, but its distribution is still restricted to central and eastern Europe. Glacial boundaries are thought to delimit the European distribution of Heterocope appendiculata (Engman 1994). Heterocope appendiculata has a Palearctic distribution, but is considered nonindigenous in the middle and lower portion of the Ponto-Caspian basin. It is thought to have spread down the Volga River from the Baltic Sea basin (Slynko et al. 2002). It had spread into the Kuybyshev Reservoir in 1957 and the Oka River after 2000 (Litvinov et al. 2009). The spread of this species may have been facilitated by the impoundment of reservoirs. After the impoundment of the Uglich and Ivankova reservoirs, specimens of Heterocope appendiculata were collected (Slynko et al. 2002). About 5 years after the impoundment of the Rybinsk Reservoir, Heterocope appendiculata and other zooplankton invaders developed large populations. This species is now one of the most abundant zooplankton species in the Kama River (Litvinov et al. 2009).

Summary of species impacts derived from literature review. Click on an icon to find out more...

Environmental	Beneficial

After its introduction to the Volga River basin, Heterocope appendiculata and other non-native zooplankton species may have formed the basis of a new food chain for planktivorous fish (Slynko et al. 2002); however, there is not enough evidence to suggest that Heterocope appendiculata will significantly alter the food web if introduced to the Great Lakes. There is insufficient information available to determine whether Heterocope appendiculata poses a threat to other species or water quality. There are no reports on how it affects or interacts with other species. It is unknown whether this species alters the physical components of the ecosystem.

There is little or no evidence to support that Heterocope appendiculata has the potential for significant socio-economic impacts if introduced to the Great Lakes.

It has not been reported that Heterocope appendiculata poses a threat to human health or water quality. There is no evidence that this species negatively impacts infrastructure, economic sectors, recreational activities and associated tourism, or the aesthetic appeal of the areas it inhabits.

There is little or no evidence to support that Heterocope appendiculata has the potential for significant beneficial impacts if introduced to the Great Lakes.

It has a relatively high concentration of eicosapentaenoic acid, an important fatty acid used in the synthesis of endohormones in fish (Galdyshev et al. 2015). It has not been indicated that Heterocope appendiculata can be used for the control of other organisms or improving water quality. There is no evidence to suggest that this species is commercially, recreationally, or medically valuable.

There are no known regulations for this species.*

*Ballast water regulations applicable to this species are currently in place to prevent the introduction of nonindigenous species to the Great Lakes via shipping. See Title 33: Code of Federal Regulations, Part 151, Subparts C and D (33 CFR 151 C) for the most recent federal ballast water regulations applying to the Great Lakes and Hudson River.

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

Control

Biological
There are no known biological control methods for this species.

Physical
There are no known physical control methods for this species.

Chemical
There are no known chemical control methods specific to this species.

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