Stellate tadpole-goby, Benthophilus macrocephalus maeotica (Kuznetsov, 1888), Benthophilus monstrous (Kuznetsov, 1888), Dolichthys stellatus (Sauvage, 1874), Doliichthys stellatus (Sauvage, 1874).

Nonindigenous Occurrences: Benthophilus stelllatus was first reported in 2011 in the Upper Dnieper River basin in Belarus (Rizevsky et al. 2013). It has been reported in the Danube River in Bulgaria (Vassilev et al. 2008). It has been reported in the Kuybyshev and Cheboksary Reservoir in Russia (Kasyanov and Klevakin 2011, Semenov 2010). It occurs in the Kiev reservoir of the Dneiper River in Ukraine (Witkowski and Grabowska 2012). This species occurs in the middle part of Don River (Sindilariu and Freyhof 2003).

Potential pathway(s) of introduction: Transoceanic shipping (ballast water)

Benthophilus stellatus does not currently occur near waters connected to the Great Lakes Basin. This species is not known to hitchhike or foul. Benthophilus stellatus is not commercially cultured, stocked, or sold in the Great Lakes region. This species has neither been observed fouling or in ballasts of ships entering the Great Lakes or in ports in direct trade with the Great Lakes. This species has a temperature range of 4 - 20°C and can tolerate salinity levels up to 12 ppt (Kottelat and Freyhof 2007, Whitehead et al. 1986). Thus, ballast water exchange regulations that require filling ballast tanks with full-strength sea water may limit the introduction of this species to the Great Lakes. Benthophilus stellatus is predicted to be introduced to the Great Lakes via ballast water (Kolar and Lodge 2002, Ricciardi and Rasmussen 1998). Benthophilus stellatus 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 (NOAA Final Report 2005). In the study, the temperature of the residual water from the vessels sampled ranged from -0.7 to 23.9°C; thus Benthophilus stellatus is likely to survive the salinity and temperature of ballast water from most NOBOB vessels.

Benthophilus stellatus has a moderate probability of establishment if introduced to the Great Lakes (Confidence level: High).

The native and introduced ranges of Benthophilus stellatus have similar climatic and abiotic conditions as the Great Lakes (Grigorovich et al. 2003, Reid and Orlova 2002, US EPA 2008). There are various habitats throughout the Great Lakes basin that match the requirements of Benthophilus stellatus (Johengen et al. 2000). This species prefers waters that are colder and less saline; thus, increased water temperatures and salinization due to climate change may make the Great Lakes a less suitable environment for it. Benthophilus stellatus has a generalist diet and feeds on invertebrates and small fishes (Kottelat and Freyhof 2007, Whitehead et al. 1986). It is likely that Benthophilus stellatus will find an appropriate food source if introduced to the Great Lakes. The presence of nonindigenous crustaceans and small fishes from the Ponto-Caspian may aid its establishment, but not to a significant degree (USGS 2012). Large piscivorous fish may prey on Benthophilus stellatus. There is potential for predators to inhibit the establishment of this species; however, similar gobies such as the round goby (Neogobius melanostomus) have established despite predation pressure (Kornis et al. 2013, Whitehead et al. 1986). Relative to gobies within and outside of its subfamily, Benthophilus stellatus has an average fecundity (Whitehead et al. 1986). 

Benthophilus stellatus has extended its range beyond the Ponto-Caspian basin. The construction of reservoirs has resulted in the introduction of Benthophilus stellatus to the Volga and Don Rivers (Ermolin 2010, Ivancheva and Ivanchev 2008, Luzhnyak and Korneev 2006). Once established in a region, it has spread moderately fast, accelerated by human activities. A year after its discovery, the abundance of Benthophilus stellatus was high (Yashanin 1982).

There is little or no evidence to support that Benthophilus stellatus has the potential for significant socio-economic impacts if introduced to the Great Lakes.
It has not been reported that Benthophilus stellatus 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 Benthophilus stellatus has the potential for significant beneficial impacts if introduced to the Great Lakes.
It has not been indicated that Benthophilus stellatus can be used for the control of other organisms or improving water quality. Other gobies such as the round goby (Neogobius melanostomus) are known to eat nonindigenous dreissenid mussels that are invasive in the Great Lakes, and may reduce their populations somewhat (Fuller et al. 2013). Dreissenid mussels are responsible for altering the water quality in the Great Lakes (Mida et al. 2010), so reducing their populations may also have an effect on water quality. However, there are no records suggesting that this particular species, Benthophilus stellatus, can act as a biological control agent for dreissenid mussels. There is no evidence to suggest that this species is commercially, recreationally, or medically valuable. Other goby species are in the market for the aquaculture trade, but there are no records that suggest that Benthophilus stellatus is commercially valuable (Whitehead et al. 1986). It does not have significant positive ecological impacts.

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. General piscicides (such as rotenone) may be used for control, but expect significant kill of non-target species.

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