Schizopera borutzkyi
Monchenko, 1967
Common Name:
An oarsman
Synonyms and Other Names:
harpacticoid copepod
Identification:
This copepod is distinguishable from many other harpacticoids that occur in the Great Lakes by its broad rostrum and long caudal rami (Horvath et al. 2001). Both the exopod and endopod on the first leg of S. borutzkyi are 3-segmented. The exopods have either 4 setae (on leg 1) or 4 spines (on leg 2) on the last segment. On the second segment of the exopod there is either 1 exterior spine (leg 1) or 1 interior spine (leg 2) (Lesko et al. 2003).
Size:
0.5–0.6 mm long. Males are typically shorter than females (Monchenko 1967; Horvath et al. 2001; Lesko et al. 2003).
Native Range:
Schizopera borutzkyi is native to the Black Sea basin (Monchenko 1974, 1995; Horvath et al. 2001).
Great Lakes Nonindigenous Occurrences:
Schizopera borutzkyi was recorded for the first time in Lake Michigan in 1998 (Horvath et al. 2001). Its continued presence in the lake was confirmed in subsequent years (Garza and Whitman 2004). It was discovered in Lake Erie in 2003 (Lesko et al. 2003).
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 Schizopera borutzkyi are found here.
Full list of USGS occurrences
Table last updated 5/1/2024
† 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:
In Lake Michigan, S. borutzkyi is found at depths of 6–15 m and has reached densities of 3700 m2 (Horvath et al. 2001). It was originally recorded in Europe by Monchenko (1967) in the Danube Delta region of the Black Sea on silt and sand at a pH of 7.6 and salinity of 0.04–6 ppt. Reproductive females carry two egg sacs ventrally (Lesko et al. 2003). The species can diapause, which likely contributed to its survival in ship ballast tanks (Panov et al. 2004).
Means of Introduction:
The introduction of this species is attributable to ballast water release (Horvath et al. 2001).
Status:
Established where recorded.
Great Lakes Impacts:
Summary of species impacts derived from literature review. Click on an icon to find out more...
There is little or no evidence to support that Schizopera borutzkyi has significant environmental impacts in the Great Lakes. Realized:
Schizopera borutzkyi has altered the species composition of nearshore harpacticoid communities, comprising up to 75% of the community at deep sites (15 m) in Lake Michigan. However, despite being the dominant harpacticoid in Lake Michigan, there is no evidence that S. borutzkyi has altered the food web or ecosystem processes, suggesting that the consequences of establishment are low (Grippo et al., 2017).
There is little or no evidence to support that Schizopera borutzkyi has significant socio-economic impacts in the Great Lakes.
There is little or no evidence to support that Schizopera borutzkyi has significant beneficial effects in the Great Lakes.
Management:
Regulations (pertaining to the Great Lakes)
There are no known regulations for this species. 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
Schizopera borutzkyi is found in shallow mud and sand at a temperature of 21°C and pH 7.6 in its native habitat of the Black Sea Danube River delta, and can tolerate a wide variety of salinities (0.04-6%), but there is no research available at this point on the significance of these parameters to control (Horvath et al. 2001).
Electron beam irradiation can be used to control microorganisms in aquatic pathways, including S. borutzkyi (GLMRIS 2012). Electron beam irradiation is a non-selective control method which exposes water to low doses of radiation using gamma-sterilizers or electron accelerators, breaking down DNA in living organisms while leaving behind no by-products (GLMRIS 2012). Ultraviolet (UV) light can also effectively control microorganisms, including S. borutzkyi, in water treatment facilities and narrow channels, where UV filters can be used to emit UV light into passing water, penetrating cell walls and rearranging the DNA of microorganisms (GLMRIS 2012).
Chemical
The Great Lakes and Mississippi River Interbasin Study (GLMRIS 2012) suggests that alteration of water quality using carbon dioxide, ozone, nitrogen, and/or sodium thiosulfate could be effective in preventing upstream and downstream movement of copepods. It should be noted that the effectiveness of these methods is likely significantly diminished against copepod ephippia.
Note: Check state/provincial and local regulations for the most up-to-date information regarding permits for control methods. Follow all label instructions.
References
(click for full reference list)
Author:
Kipp, R.M., J. Larson, T.H. Makled, and A. Fusaro
Contributing Agencies:
Revision Date:
9/12/2019
Citation for this information:
Kipp, R.M., J. Larson, T.H. Makled, and A. Fusaro, 2024, Schizopera borutzkyi Monchenko, 1967: 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=2374&Potential=N&Type=0&HUCNumber=DGreatLakes, Revision Date: 9/12/2019, Access Date: 5/1/2024
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.