Quark Archipelago. 02/02/04; Western Finland; 63,699 ha [formerly called Valassaaret and Björkögrunden Archipelago]; 63°26'N 021°25'E. Natura 2000 SPA and SCI, Baltic Sea Protected Area, Shore Conservation Programme. Situated in the narrowest and shallowest area of the Gulf of Bothnia at the northern limit for many marine species, such as Eider and Blue Mussel. The archipelago bird fauna is exceptionally rich, e.g., more than 1,700 pairs of Arctic Tern and 3,800 pairs of Black Guillemot are breeding at the site. Shallow waters are important staging areas for waterfowl during migration and molting periods, and the archipelago is habitat for the endangered Grey Seal. The outer archipelago is composed of several groups of islands divided by shallow open sea areas, and the Valassaaret Islands are characterized by Storskär Island surrounded by about 80 small, nearly treeless and stony islands and islets. Because of strong land upheaval, virgin shores, such as coastal meadows and natural forests in primary succession stages, are relatively quickly born. Treeless islets are abundant and morainic ridges are broad. The main threats for the site are damage through oil pollution, followed by notable impacts of the American Mink in bird colonies. The Valassaaret Biological Station on Ebbskär Island is a bird monitoring station and an education site. Significantly extended from 16,730 ha and renamed in February 2004. Ramsar site no. 6. Most recent RIS information: 2005.