Popella guernei (Richard, 1888), Siatella durbini (Labbé, 1927).

Nonindigenous Occurrences: The extent of the modern geographical native range of Calanipeda aquaedulcis is still under revision. It was introduced to the Aral Sea from the Sea of Azov in 1960–1965 to increase the productivity of zooplankton and fish (Karpevich 1975; Aladin et al. 2019). It is thought to be recolonizing some Spanish estuaries, and was recorded for the first time in the Ria de Plencia around 1980 and the Bilbao estuary in 2001 (Villate and Orive 1981; Albaina et al. 2009; Uriarte et al. 2016). This species is also spreading northward into the reservoirs of the Lower Don (Matishov et al. 2016) and Volga Rivers (Lazareva 2018).

Potential Pathway(s): Transoceanic shipping (ballast water)

Calanipeda aquaedulcis has not been reported to occur in North or South America (Svetlichny et al. 2012b). There is no evidence that suggests that Calanipeda aquaedulcis is currently stocked, cultured, or sold commercially in the Great Lakes region. This species is not known to attach to recreational gear and is not being transported through the Great Lakes region. The potential risk for invasion originates from the established populations in the Mediterranean and Ponto-Caspian regions (including the Black Sea, Caspian Sea, Mediterranean Sea, and the Sea of Azov) (Alekseev and Sukhikh 2020). There are multiple ports in these regions (e.g., Ashdod, Israel; Tunis, Tunisia; and Oran, Algeria) that have direct trade connections to the Great Lakes (U.S. EPA 2008; NBIC 2009).

There is a possibility for Calanipeda aquaedulcis to be introduced to the Great Lakes if it survives overseas transport originating in the Baltic Sea. It produces resting eggs that may be resistant to salinity increases during ballast exchange, but may be flushed in the process (Wonham et al. 2005; Frisch et al. 2006; Svetlichny et al. 2012b). The adult forms can tolerate a wide range of salinity (0–33 ppt) and may survive ballast water exchange as well (Villate and Orive 1981; Svetlichny et al. 2012a).

Calanipeda aquaedulcis has a moderate probability of establishment if introduced to the Great Lakes (Confidence level: High)

The native range of Calanipeda aquaedulcis has similar climatic and abiotic conditions to that of the Great Lakes (Reid and Orlova 2002; Grigorovich et al. 2003; U.S. EPA 2008). Calanipeda aquaedulcis is found in the Mediterranean coastal areas of Europe, which have summers similar to the Great Lakes, and the Sea of Azov, which has winters as cold as those in the Great Lakes (Svetlichny et al. 2012b). Calanipeda aquaedulcis can tolerate a broad range of temperatures, oxygen levels, and salinities. Due to its ability to thrive in low temperatures and tolerate low oxygen levels, it is likely that Calanipeda aquaedulcis is able to overwinter in the Great Lakes basin if introduced. This species can adapt rapidly to fresh and salt water environments due to its osmo-independent metabolism (Svetlichny et al. 2012b). Increased salinization attributed to climate change may render the Great Lakes more suitable for this estuarine species (Brucet et al. 2008). It is found primarily in oligotrophic waters, but can survive in eutrophic environments (Saygi et al. 2011; Svetlichny et al. 2012b). It is established in Lesina Lagoon, Italy, which experiences many of the same pollution issues that affect the Great Lakes (agricultural, wastewater treatment plants, watershed resident populations (Brugnano et al. 2011).

Due to its flexible, omnivorous diet, it is likely that Calanipeda aquaedulcis will find a suitable food source if introduced to the Great Lakes (Brucet et al. 2008). Calanipeda aquaedulcis may be preyed on by freshwater fish; however, it is unlikely that these predators will specifically target Calanipeda aquaedulcis. Calanipeda aquaedulcis produces resting eggs that may be capable of overwintering in the Great Lakes (Frisch et al. 2006; Svetlichny et al. 2012b). The egg densities that this species produces may be larger than those produced in its native range due to the lower salinity of the Great Lakes (see Ecology). The discharge of resting eggs in ballast sediment is thought to be infrequent and moderate in size.

Calanipeda aquaedulcis has expanded outside its native range considerably. This species can rapidly establish a dominant population after introduction. Ten years after its introduction to the Aral Sea in the 1960s, Calanipeda aquaedulcis became one of the dominant zooplankton species and consequently eliminated other zooplankton (Mirabdullayev et al. 2004). However, this species disappeared from the region in 1997. It has also spread nearly 1700 km from the Caspian Sea through the Volga River basin and its reservoirs in less than 50 years (Lazareva 2019).

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

Environmental

If Calanipeda aquaedulcis is established in the Great Lakes, it may outcompete native species for available resources. It became one of the dominant species in the zooplankton communities after establishing in the Aral Sea (Mirabdullayev et al. 2004), replacing the native copepod Arctodiaptomus salinus and cladoceran Moina mongolica (Mordukhai-Boltovskoi 1972; Karpevich 1975; Plotnikov et al. 2016). Calanipeda aquaedulcis is also the dominant copepod in summer in the estuary of Bilbao, Spain (Albaina et al. 2009, 2016). It occurs in high densities (up to 7000 ind/m3) in reservoirs of the Volga River but made up no more than 2% of total zooplankton biomass (Lazareva 2019).

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

It has not been reported that Calanipeda aquaedulcis 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 Calanipeda aquaedulcis has the potential for beneficial impacts if introduced to the Great Lakes.

Calanipeda aquaedulcis could potentially contribute to another food source in the food web since the majority of freshwater fish eat copepods. It was introduced to the Aral Sea from the Sea of Azov in 1960–1965 to increase the productivity of zooplankton and fish, however, no significant long term impacts were reported (Karpevich 1975; Aladin et al. 2019).

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 biological control methods for this species

Chemical
There are no chemical control methods for 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.