Ducks carrying tiny satellite transmitters on their backs are being tracked in Mai Po wetlands by scientists trying to determine their migratory routes and their connection to deadly bird flu viruses.
Meanwhile, tempers are flaring over government-imposed restrictions on the import of live chickens. Last Saturday, a chicken trader dived into Victoria Harbour in protest and, earlier this week, a band of poultry sellers tried to break a police cordon at the Murray Building in Central. They are furious that only 7,000 mainland chickens a day are being allowed in during the Lunar New Year instead of the usual 20,000.
The spectre of bird flu is with us again, as it has been periodically since the H5N1 - or bird flu - virus killed six of the 18 people who contracted it here in 1997 and led to an unprecedented mass culling of some 1.4 million birds and the closure of the trade for two months.
Scientists said that stopped the virus from turning into the sort of pandemic not seen since we gave Hong Kong flu to the world in 1968.
But despite four outbreaks in the 11 years since the first, and a global re-emergence of the deadly virus since 2003, the early fears have given way to complacency because a flu pandemic has failed to materialise.
The poultry trade is angry at having to carry the can for a public health scare when they believe H5N1 bird flu was long considered a 'chicken plague', affecting only poultry.
There is particular fury this winter that the supply of fresh chickens from the mainland is being kept at a normal-day level for the Lunar New Year, the most important festival on the Chinese calendar and the time they would normally expect to make a killing.