Herpesvirus anguillae (HVA) was detected during disease investigations of European eel, Anguilla anguilla L. at two stillwater fisheries in central England. These represent the first records of HVA from UK eels. Both mortalities were eel‐specific and took place during August 2009 and July 2010 at water temperatures between 17 and 19.4 °C. Pathological changes consistent with HVA infection included haemorrhaging in the fins, skin lesions and necrosis within the gills and liver. Transmission electron microscopy revealed active virion replication within the gill tissue. An initial assessment of risk is presented, indicating that HVA represents a high disease risk to UK eel stocks. However, further studies are required to establish the distribution of HVA before a reliable assessment of impact may be obtained. Until then, the detection of HVA holds important implications for eel conservation and management, in particular eel stocking activity.

In England and Wales, freshwater anglers have shifted their behaviour towards visiting catch-andrelease lake fisheries that are intensively stocked, mainly of large common carp, Cyprinus carpio L., to maintain high catch rates. Of 187 fish kills investigated in these intensively stocked lake fisheries in 2004 and 2005, most occurred between April and June and were mainly caused by parasitic or bacterial infections. Bacteria were usually associated with ulcerative diseases caused by strains of the bacterium Aeromonas salmonicida (Emmerich & Weibel) and secondary infections of opportunistic bacteria of the Genus Aeromonas (excluding salmonicida) and Pseudomonas. Parasites involved in fish kills included Ichthyophthirius multifiliis (Fouquet), Chilodenella sp., Ichthyobodo necator (Henneguy) and Argulus sp. Outbreaks were typically in fisheries with high extant stock densities (>1500 kg ha )1 ) and sub-optimal habitats, for example of low habitat heterogeneity with few macrophytes in the littoral zone. Recent stocking was also a key factor when only carp was affected. Thus, certain fisheries management practices that aim to enhance fishery performance may instead trigger fish kills during spring.K E Y W O R D S : bacteria, Cyprinus carpio, fisheries management, parasite, virus.