So is it a genetic predisposition that makes the terns more susceptible to the flu? Or is it because of their behavior that they are congregating and spreading the virus among themselves?

That is a fantastic question and one that's quite hard to answer.

When research has been done in looking at immune system architecture and how that might predispose certain species to have an influenza, there's often been a lot of focus on poultry.

why poultry are so hard hit, what's going on with the immune system architecture of chooks that make them so seemingly vulnerable to bird flu, and then maybe contrasting to the typical reservoir of bird flu, which are ducks, and sort of comparing those groups and why they differ.

But apart from that, there hasn't been too much work exploring the immune system architecture of various wildlife species or sort of doing any attempts to figure out why certain species are more susceptible or seemingly susceptible than others.

So it's kind of hard to answer if there is any sort of immune system architecture related thing that causes certain species to be more or less predisposed.

But what we do know is that behavior has a big part in how exposed certain species of birds are to the virus.

Where is your focus at the moment?