It covers a shallow, overgrown lake (with its surroundings) located 5 kilometers east of Lwówek, on the south-eastern side of the Zgierzynka village. A number of water fowl species, including rare and protected ones, have their hatching site here, in hard-to-reach places. Almost 140 bird species have been seen here (including 60 during hatching); greylag geese are the most peculiar in this respect (the only hatching site in the Wielkopolska region). In autumn it proves to be a wonderful bird watching site, particularly when it comes to cranes, which gather here in huge flocks before flying away.