Black-striped pipefish

Syngnathus abaster has invaded areas with a high diversity of ichthyofauna (Lendhardt et al. 2011). This species produces twice as many eggs as the congener S. taenionotus and has four broods per reproductive season, with an average of 100 offspring, as opposed to two broods (Franzoi et al. 1993). Males carry eggs and larvae in brood pouches, making it more likely the early life history stages of pipefish can survive harsh environments (Snyder et al. 2014).

The most important food item for this species are harpacticoids of the genus Tisbe, though phytal amphipods and other phytal organisms also contribute (Franzoi et al. 1993). There are over 34 harpacticoids species in the Great Lakes area (Hudson et al. 1998). Several harpacticoid copepods from Eurasia have been introduced into the Great Lakes (Kitokra hibernica and N. incerta). These species would provide potential food sources for Syngnathus abaster. No enemies have been mentioned in the native or introduced range, but as a slow-moving species, it may be vulnerable to predation by larger fish such as trout and salmon.

Potential pathway(s) of introduction: Transoceanic Shipping

Ballast water exchange is predicted to have a low effectiveness for Syngnathus abaster, as it has high salinity tolerances (Snyder et al. 2014). This suggests that it could survive transportation via ballast water for introduction into the Great Lakes. This species is not extremely abundant, so the frequency of ballast uptake is likely small.

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

The Great Lakes include a large amount of the preferred habitat for Syngnathus abaster (muddy vegetated bottoms with slow current). The wide distribution of this species in heavily-disturbed rivers of Europe indicates it would tolerate pollution and other disturbances which are found in various parts of the Great Lakes. There are no reported enemies in either its native or introduced range; however, it is a slow-moving species so it may be vulnerable to predation by larger fish, such as salmon and trout.

There is insufficient information available to determine whether Syngnathus abaster poses as 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 Syngnathus abaster has the potential for significant socio-economic impacts if introduced to the Great Lakes.

It has not been reported that Syngnathus abster 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 area it inhabits.

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

It has not been reported that Syngnathus abster can be used for the control of other organisms or improving water quality. There is no evidence that this species is commercially, recreationally, or medically valuable. It does not have a significant positive ecological impact.

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
Of the four chemical piscicides registered for use in the United States, antimycin A and rotenone are considered general piscicides, but no studies have been found about their effects on S. abaster (GLMRIS 2012).

Increasing CO2 concentrations by bubbling pressurized gas directly into water or by the addition of sodium bicarbonate (NaHCO3) has been used to sedate fish with minimal residual toxicity, and is a potential method of harvesting fish for removal, though maintaining adequate CO2 concentrations may be difficult in large/natural water bodies (Clearwater et al. 2008). CO2 is approved only for use as an anesthetic for cold, cool, and warm water fishes the US, not for use as euthanasia, and exposure to NaHCO3 concentration of 142-642 mg/L for 5 min. is sufficient to anaesthetize most fish (Clearwater et al. 2008).

It should be noted that chemical treatment will often lead to non-target kills, and so all options for management of a species should be adequately studied before a decision is made to use piscicides or other chemicals. Potential effects on non-target plants and organisms, including macroinvertebrates and other fishes, should always be deliberately evaluated and analyzed. The effects of combinations of management chemicals and other toxicants, whether intentional or unintentional, should be understood prior to chemical treatment. Other non-selective alterations of water quality, such as reducing dissolved oxygen levels or altering pH, could also have a deleterious impact on native fish, invertebrates, and other fauna or flora, and their potential harmful effects should therefore be evaluated thoroughly.

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