Collaborative research led by the University of East Anglia has identified one of the causes of recent deaths in UK European brown hare populations. Working together with diagnostic laboratories in England, Scotland and Germany, the first UK cases of rabbit haemorrhagic disease virus type 2 (RHDV2) have been detected in dead hares found in two locations – Essex and Dorset. Researchers from UEA joined forces with Suffolk, Norfolk and Essex Wildlife Trusts, the Department for Food and Rural Affairs (DEFRA) and the APHA Surveillance Intelligence Unit to investigate the cause of hare deaths following reports of sick and dead hares from members of the public.
Lead researcher Dr Diana Bell, from UEA’s School of Biological Sciences, said: “RHDV2 normally affects rabbits, but the disease is known to have jumped to European brown hares in Italy, Spain, France and Australia.
“This is the first time that RHDV2 has been found in hares in the UK.
“RHDV2 is one of several pathogens we are finding in dead hares and it is too early to say which is currently the primary cause of the hare die-off. We are continuing to investigate other causes for the deaths.”
Nationally, brown hares have experienced a decline of more than 80 per cent over the past century due to changes in agricultural practice. The intensification of agriculture has limited their supply of food and habitat.
But concerns about new diseases were raised after landowners, farmers and other members of the public started reporting sightings of obviously sick and dead hares in September 2018.
Members of the public were urged to photograph sick and dying hares and, most importantly, collect the bodies for autopsy so that the impact of new and existing diseases on hare populations could be determined.
Dr Bell said: “We are enormously grateful for the continuing tremendous response from the British public in reporting dead hares to us and helping us collect them for post mortems. This is good example of citizen science.
“Hare deaths are still being reported to us and we are still collecting the bodies to test for RHDV2 and other pathogens that could be contributing to the decline.
Hares can be distinguished from rabbits in a number of ways. Hares are larger than rabbits, with longer hind legs and black-tipped ears that are as least as long as their heads.
“It’s still too early to say which diseases are most common at the moment but the expanding dataset will allow us to map reported mortalities over time.”