Quick, call Alfred Hitchcock. A flock of strange birds swooped over 7th and Montana this morning and something tells me not even Tippi Hedren could scare them away. They landed on a telephone pole on 7th Street and sat there screeching in unison for what seemed like an eternity. Perhaps they were trying to warn passersby about the rainstorm that was brewing. I, for one, opened my umbrella as I passed by ... but then, again, who wouldn't with a collection of birds like that overhead?