- Voicing an entire flock of birds, in a single take.
- In a 2015 interview (which also included Peter Cullen), Welker is specifically asked about this claim and does not remember ever doing it...but what he believes the rumor originally referred to is just as amazing: During his stand-up comedy years, he once voiced 14 ducks simultaneously singing "We Wish You a Merry Christmas".
- Welker once appeared on Manny the Uncanny and did a capuchin monkey distress call. And he got a reaction from actual capuchin monkeys. That's how good the guy is.
- The sheer amount of roles that Frank's done (a lot of which are animal walla/animal sound effects that sound just like the real thing) is quite an impressive feat.
- He has consistently been the voice of Fred Jones since 1969 with the only time he hasn't voiced Freddy in being A Pup Named Scooby-Doo. Now that's dedication!
- Frank Welker voiced both Godzilla AND Mothra in a spoof shown in a 2001 segment of Evil Con Carne.
Mothra: He who smelt it dealt it!