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Urban Riverfly

Urban Riverfly uses an extended list of 14 aquatic invertebrate groups (including the original eight ARMI target groups), that can be used across a number of different river systems, with trained volunteers employing the same survey method as with ARMI (a three minute kick sample and one minute hand search) to collect samples. The six additional invertebrate groups mean that Urban Riverfly provides greater sensitivity and evaluation of pressures compared to ARMI. The extra groups comprise of: Worms, Snails, Beetles, Leeches, Blackfly larvae (Simuliidae) and Freshwater hoglouse (Asellidae). The 14 Urban Riverfly groups include easily identifiable, more pollution tolerant and commonly recorded invertebrates, especially in urban and modified rivers.

Urban Riverfly scores are impacted both positively and negatively by abundance so they are more reflective of the WHPT methodology used by the Environment Agency. Pollution tolerant groups, such as Leeches, Worms and Freshwater hoglouse, will negatively affect the Urban Riverfly score as abundances increase. A pilot of this scheme has been ongoing in the Midlands where both new volunteers and existing ARMI volunteers attended a one day Urban Riverfly training workshop. Currently, survey results from the Urban Riverfly pilot scheme are stored online in Cartographer.