Another famous animal resident of Mountain Lake was Myrtle, a non-native whooper swan who was flightless after being pinioned. Myrtle was well-known in the neighborhood for disrupting traffic while crossing Lake Street and stealing snacks from the nearby Lake Market at 12th and Lake. Other antics included visiting regular park patrons, watching tennis players, and attending picnics. San Francisco Zoo officials believed the swan had imprinted on people sometime in the past. Her last human "mate" was local resident Chuck Lantz, who lives next to Mountain Lake Park. Shortly after dawn each morning Myrtle would loudly "whoop" at his back door, moving around the block and up his stairs until he responded and walked her back to the park.