Found about this thing scrolling through thomann products.
Instantly checked on YouTube what it's about, this Bird Pipe.
I was fascinated, so I made my order.
Pretty fun thing, but don't except it's just simple to use. It requires some effort to learn, so at first I was disappointed and then after some time I found the right spot so it will make this sounds. Don't except that you will start singing like a real bird, though pretty close! It is fragile, so be careful and always dry it after use with tissue.
Also you can imitate not only bird sounds with this Pipe. Search on YouTube "how to use wacky whistle", there's a video of a guy who explains how to make different sounds.
Experiment and have fun!