Knowing where, when and for how long mallard ducks -- natural carriers of avian influenza -- stop and rest as they migrate can help predict the probability that they will spread bird flu to backyard ...

Knowing where, when and for how long mallard ducks—natural carriers of avian influenza—stop and rest as they migrate can help ...

Knowing where, when and for how long mallard ducks – natural carriers of avian influenza – stop and rest as they migrate can help ...

Knowing where, when and for how long mallard ducks - natural carriers of avian influenza - stop and rest as they migrate can help predict the ...

It's a question that has perplexed Chinese-American takeout fans for decades: Exactly how much duck is in duck sauce? The ...