THREATENED MIRES AND PEAT MOSSES IN GORSKI KOTAR
Mires are a special type of wetland habitat in which large quantities of water are retained among low-growing vegetation. Mires are typically made of various types of mosses and other low-growing plants, the remains of which accumulate on the mire as they grow year after year. Because the dead plants decay without the presence of oxygen, they do not decompose completely and are gradually carbonized, creating layers of peat.
Although mires are a true rarity anywhere in Croatia, most of the mires in our county could once be found in Gorski Kotar which has suitable climate conditions (lots of precipitation). Both in Croatia and in Gorski Kotar, mires are actually ice-age relics on which many rare species – glacial and boreal relics – grow. The most important mire-builders among mire vegetation are various species of mire mosses, in particular, peat mosses (different species of the Sphagnum family) in certain types of mires. Today, the existence of most of the mires in our region is threatened.
The cells of peat mosses (Photos 1 and 2) have the ability to retain large quantities of water. When we walk upon these waterlogged terrains covered in mire mosses, our feet sink into the wet, soft peat substrate, and small pools of water form in the footprints we leave. The local population has a variety of names for these marshy terrains or bogs. In some parts they are called pištaline (squeaking meadows) and in others, sunđerak (on the Velebit range, for example) and sunger (in Gorski kotar), because of their ability to absorb enormous amounts of water, like a sponge (sunđer = sponge). Drivers of off-road vehicles are attracted to this type of terrain because it gives them the unique opportunity of simulating mud-bogging, a type of off-road racing. The huge damage this causes to threatened habitats and species goes without saying!
The disappearance of mires in which mire mosses and rare plants grow, such as the insect-eating sundew, has especially been pronounced in the past several decades in the Gorski Kotar region. In Gorski Kotar, mires with peat mosses and sundews have mostly developed on silicate, watertight substrates in depressions alongside small creeks. In locations such as these, several water reservoirs have been built, and new ones are being planned (for example, the lake at Križ Potok).
Up to date, some ten of the most important locations of peat mosses, sundews, mire mushrooms and other exceptionally rare mire species and habitats in Gorski Kotar have been flooded by artificial lakes. The few remaining sites have suffered considerable change due to encroachment by forest vegetation, changes in water regimes, the construction of logging trails, the use of heavy forest machinery, and off-road driving through mires or in their immediate vicinity (Photo 3). Hence, we can say without a doubt that mires are among the most threatened types of habitats in Gorski Kotar, and what “remnants of remnants” are left deserve to be given protection. We invite all “relevant stakeholders” to take part in this campaign.
Photo 4. round-leaved sundew (Drosera rotundifolia) – one of the most endangered bog plant species in Gorski Kotar