Kalkskär is a small islet and part of <a href="https://en.wikipedia.org/wiki/Svenska_H%C3%B6garna" class="extiw" title="w:Svenska Högarna">Svenska Högarna</a>, a  small group of islands in Stockholm Archipelago. In june, 
thousands of male common eiders (<i><a href="//commons.wikimedia.org/wiki/Somateria_mollissima" title="Somateria mollissima">Somateria mollissima</a></i>)  come there to moult.
<a href="//commons.wikimedia.org/wiki/User:ArildV" title="User:ArildV">Arild Vågen</a>
<span class="int-own-work" lang="en">Own work</span>