Note financial figures.
The birds are starving, with empty stomachs and breast muscles shrinking as their ailing bodies burn muscle tissue to survive, say people who have found and examined the birds.
"They also feel lighter than they should," said Mike Patterson, an independent researcher in Astoria who keeps track of the trends.
"The first animals that are affected usually are calves, they might show things like just being off colour, or there might be a bit of scouring over a couple of days and then, you know, they'll die quite quickly," he said.
The cause of the rabbits' deaths is unknown, but "the situation is being handled as a highly contagious, acutely lethal disease," according to a news release.
They were of normal weight and eating well before their deaths, the release said.
There "were no visible signs of distress or abnormal behavior within hours" of their deaths.
Experts from around the world are launching a campaign to tackle a mysterious killer fungus - which threatens to make frogs extinct.
The strange fungus has wiped out 170 species of frog in the last decade and an additional 1,900 species are threatened, but nobody has yet found a cure.
'This is the precedent of a disease working its way across an entire species on the scale of all mammals, all birds or all fish.
'Humans would be absolutely stupid if they didn't pay attention to that.'
Amphibians - of which frogs make up the majority - are a vital part of the food chain, eating insects that other animals don't touch and connecting the world of aquatic animals to land dwellers.
Without amphibians, the insects that would go unchecked would threaten public health and food supplies.