The total area of Gaidžiabalė is 171,9 ha. The most important natural habitats of this reserve are located in two places and cover an area of over 110 ha. From a natural point of view, it is a very valuable territory, first of all, as one of the few, almost natural, highland bogs in Northern Lithuania. In Reserve there live even several bird species which are included in the Lithuanian Red Book, such as sketsakalis, gray winches, tikutis, middle-sized kuolinga.
Many decades ago, peat was mined in this area. Over a long period of time, the swamp recovered naturally, without human help.