Ponto-Caspian gammarids: Add chemicals to the water

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms
    not assessed

Study locations

Key messages

  • A controlled laboratory study in the UK found that iodine solution, acetic acid, Virkon S and sodium hypochlorite added to freshwater killed invasive killer shrimp, but were considered impractical for field application. Methanol, citric acid, urea, hydrogen peroxide and sucrose did not kill invasive killer shrimp when added to freshwater.


About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A controlled laboratory study in 2011 in England, UK (Stebbing et al. 2011), found that when added to freshwater, iodine solution, acetic acid, Virkon S and sodium hypochlorite killed the killer shrimp Dikerogammarus villosus, but methanol, citric acid, urea, hydrogen peroxide and sucrose did not. For iodine solution (FAM30) there was 100% mortality within 15 minutes when the shrimp were placed in solutions of 4-6 ml per litre. However, FAM30 is an irritant and so was not considered a practical control method. For acetic acid, a 10% solution was required to kill all the shrimp in 15 minutes. At lower concentrations, no shrimps died during the test period. However, fifteen minutes was considered too long for acetic acid to be a practical control method. For Virkon S, all shrimp exposed to a 1% solution died within 15 minutes, with half dying within eight minutes. However, Virkon S has a relatively short shelf life and a capacity to bleach and can damage equipment and so was not considered a practical control method. For sodium hypochlorite, at 50,000 parts/million, half of the shrimp were killed within 4.5 minutes. However, at that concentration it is lethal to humans and so is not practical. Equipment containing shrimp could be soaked in sodium hypochlorite at 200 parts/million for over an hour, but is considered impractical. None of the shrimps died when exposed for 15 minutes to methanol (1 or 10 %), urea (1 or 10 g/litre), citric acid (15 or 150 mg/litre), hydrogen peroxide (100 mg/litre), or sucrose (10 or 100 g/litre. All tests were conducted on 5 captive shrimp. Dead and live shrimp were counted.

    Study and other actions tested
Please cite as:

Aldridge, D., Ockendon, N., Rocha, R., Smith, R.K. & Sutherland, W.J. (2020) Some Aspects of Control of Freshwater Invasive Species. Pages 555-87 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Control of Freshwater Invasive Species

This Action forms part of the Action Synopsis:

Control of Freshwater Invasive Species
Control of Freshwater Invasive Species

Control of Freshwater Invasive Species - Published 2017

Control of Freshwater Invasive Species Synopsis

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