Today is Bert's birthday...
...and we celebrate with a vintage pigeon extravaganza! A couple things are noteworthy here: first, this is part of a street story rather than an insert (according to the Muppet Wiki, it dates from 1978). Second, it involves the late Mr. Hooper, who gets probably the funniest line in the whole piece: "You're..telling..me!"
Frank Oz is magnificent here. His commitment to the concept makes the whole thing work, from the ad libs ("No fighting!" and "What precision!") to the show biz slang ("That was socko, kids!") to the uncomfortable asides ("Where is the ice?") to the one-sided conversations with the pigeons.
Ironically, the pigeons seem the most active when Bert is upstaging them. But that actually makes it funnier, that they just stand around when they're supposed to be performing, kind of like that old Looney Tunes frog.
Happy birthday, Bert!