I Don't Know What Bird Larry Drew's Whistle Sounds Like, But I Want It Dead

Interim coaches need to find some way to reach their players after having the responsibilities of a head coach suddenly thrust upon them during the season. Larry Drew’s approach to communicating with the Cavs is avian in its nature.

The whistles definitely sound like some sort of bird call that I’ve heard before, either in a zoo or out in the wild. Please help me identify which species this is so I can find it and end its existence. Thanks.