Some of the revelations:
"Winged Migration": The birds were not wild birds but raised for the intended purpose of filming them.
"March of the Penguins": Penguins are not monogamous and mate for life, as the film would lead us to believe. (They mate seasonally.)
In "Mighty Times" Supposedly historical footage was reenacted.
From a wildlife documentary shoot:
We tried to shoot a few, and missed both of them. Unbeknownst to me, the [animal wrangler] broke the next rabbit’s leg, so it couldn’t run. So we got one. On the next take, they then asked, “Should we break its leg again?” . . . the DP [director of photography] was sitting there, saying “No, I’m sure you wouldn’t want to do it,” but nodding his head yes. I made the decision, let them break it. I regret it. It eats me up every day. I can sort of rationalize this, that it might be killed by a natural predator. But for us to inflict pain to get a better shot was the wrong thing to do.