Podiceps cristatus  

Podicepses live only in the lakes and they're  protected by law.

My own observations of double-pick duck I have done on Patulskie Lake near Koscierzyna City. Birds were timid, but I have boat and I could approach to be quite close to them. I think I must say more about the observation. Frightened double-pick duck dive very deep under water and come forth far away (and jokes about observator). This time was diffrent: On the lake I saw few double-pick ducks. When I approached to them I saw, that it were parents with children. The litle double-pick ducks couldn't dive, so they had to do the emergency plan: One of the parents tried to draw my mind, and the second one put its children on its back and swam away very quickly. Everyone who have heard that story was full of admiration for double-pick ducks. I decided it'll be great subject for my project!