In the Scottish Highlands, the Lochaber Mountain Rescue Team recently has been called out twice to investigate what reportedly sounded like emergency whistles being blown by walkers. But, after two fruitless searches the noise is suspected to be the shrill whistling of Sika deer.

Sika stags make a whistling sound as a warning and during mating season. According to the BBC article, they can also make “raspberry noises.”

You can read the article on the BBC website — and listen to an audio clip of Sika stags that, while odd, does not prompt me to call my local search-and-rescue group. Maybe whistles sound different in the Highlands.

via Outdoors Magic