They're cute, friendly and fantastic with spicy salt. But quail are also potential killers, offering an ideal habitat for the breeding of deadly disease, specifically, avian influenzas. So concerned were city authorities about the risk in early 2003 that the director of agriculture placed harsh restrictions on farming quail, a decision endorsed yesterday by the Court of First Instance. The restrictions involve complete segregation of quail, alive or dead, from other forms of livestock. Farms have to be at least 500 metres from other operations, and distribution channels have to be completely separate and pre-approved by the Agriculture, Fisheries and Conservation Department. Mr Justice Michael Hartmann backed the decision after hearing an application for judicial review brought by a couple whose application for a quail farming licence was refused around the time the new measures were implemented. A blanket ban on quail farming has since come into effect. The judge said the director's 2003 decision was justified given the emerging evidence on the quail's possible role in the spread of bird flu and the paramount importance of protecting Hongkongers. He said it was unfortunate for Mo Chun-hon and wife Yeung Sau-mui that fears over bird flu meant they could not carry on farming quail, despite their belief they had fulfilled the licence requirements. Mr Justice Hartmann said: 'Bearing in mind the very real threat posed to the community ... by the spread of a mutant strain of avian influenza, the director was under an obligation to take all measures as were necessary.' Each party was ordered to pay their own costs.