Procambarus crayfish control: Add chemicals to the water

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Key messages

  • One replicated, controlled study in Italy found that red swamp crayfish could be killed using the natural pyrethrum Pyblast at a concentration of 0.05 mg/l, but that application to drained crayfish burrows was not effective.


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. One replicated, controlled study in 2009 in Italy (Cecchinelli et al. 2012) found that natural pyrethrum (Pyblast) concentrations of 0.05mg/l and higher resulted in 100% mortality of red swamp crayfish Procambarus clarkii under laboratory conditions, 95% mortality when 0.05mg/l Pyblast was applied to a drainage channel, but no mortality following application of 0.05 mg/l Pyblast into active crayfish burrows. For the drainage channel study, two 50m-long upstream control transects were compared with two downstream transects treated with 0.05 mg/l Pyblast, and mortality of crayfish in each transect was monitored recorded every 24 h for 96 h.  For the burrow study, a 0.3 l solution of 0.05 mg/l Pyblast was injected up to 2 m inside active crayfish burrows after the channel had been drained. Crayfish population changes were assessed by comparing capture rates in four replicated, baited traps before and after the treatment.

    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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