One thing it can be hard for people to get is that bird are not people and have an entirely different set of standards for their mental and physical health. One somewhat comical example of this was a woman who was trying to convince me that we should increase the leafy greens component of our birds diet. The conversation went something like this:
"So how much of their diet is things like nuts and berries?"
"Actually none. [I say 'actually' a lot. It's kind of a filler word that sounds better than 'ummmm']. Most of our birds are entirely carnivorous, and eat nothing but meat."
"Well do you ever give them a choice?"
"Nope. We feed all of our birds nothing but meat."
"But vegetables are good for you!"
(getting a little bit annoyed) "Not for birds of prey. In the wild they eat nothing but meat, so that's what we give them here."
"Well you should at least give them a choice! It's cruel not to. Everybody knows that vegetables are good for you!"
"Actually, most birds of prey cannot digest cellulose very well, and if they ate too much of it, they would die."
The conversation actually went on for a couple minutes after that, in which the lady just refused to believe that raptors bodies worked any differently from her own.

(A quick story about the opposite problem: I had a lady the other day who believe that birds were completely different from people. She asks whether or not birds could regenerate bones "like a starfish," whether they had red blood, and whether or not they had hearts. It was like she thought they were some sort of gigantic invertebrates.)

A much more common complaint we get is about the birds in the weathering yard, which are tethered down for eight hours a day for their own safety. We get lots of people who will actually shout at us telling us how cruel it is and how horrible we are for doing it (e.g. crazy French lady from a few posts down.) So I do the whole routine about them being three different species, and how it's healthier than being inside all day, but the main point is that birds of prey really do spend most of their time just perched in one place. If they are not hunting or traveling from one place to the other, they really don't fly at all. They hunt for their own food, and sometimes they will fail for long periods of time, so it is much better to conserve energy. I then point out that they do not strain at their leashes, and tell them to look at all of our untethered birds, none of which are moving. But they'll have none of it. I often make the joke that I'm tied out here, unable to leave, for just as long as they are, and I don't even have the option of just not cooperating that day (our birds sometimes don't come out if they simply don't want to), but I always forget that it's a terrible idea to joke with someone at the height of righteousness.

These are also the same people who comment that our birds "look sad." I always do the the little "sad and happy don't really apply to these birds as much as 'safe and endangered' and 'full and hungry'" but I sometimes just want to scream "Look lady. How do you think you can tell that? They don't even have any face muscles! Sitka their has her leg up, her feathered poofed, and she looks just as happy as happy can be. And do you really think we would want our birds to be 'unhappy'? We're a BALD EAGLE HOSPITAL. Would I have flown 4000 miles and being standing out here in the 50 degree August rain if I didn't care about birds?" Maybe on my last day.

But I admit that we sometimes don't help things on tours. Especially with the hyper-empathetic type that I mentioned in my previous post, it's hard not to try to make the birds more human to connect better with people. A lot of things are just more easily communicated in human terms, but I try to do the best that I can to emphasize that these are just shorthand for much more complex animal behaviors.

But more seriously it can be hard sometimes not to anthropomorphize the birds in order to