English - Convention on Biological Diversity

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COUNTRY STUDY FOR BIODIVERSITY OF THE REPUBLIC OF MACEDONIA
as much as 500 tonnes. In the past few years it has been reduced to 70 tonnes, dropping
to only 25 tonnes in 2002.
The accelerated succession of this lake ecosystem is evidenced by the appearance of
the Calanoid copepod (Eudiaptomus gracilis), a typical representative of marsh
ecosystems, which was recorded in Doyran Lake for the first time in 1995. In order to
restore the disturbed environmental balance, efforts have been made to bring additional
quantities of water to the lake, which is expected to improve the state of the biological
communities within the lake ecosystem.
The status of riverine ecosystems in the Republic of Macedonia is also alarming.
Almost all of the rivers are under great direct and/or indirect anthropogenic pressures.
The situation with the Vardar River, which is the major recipient of all types of
wastewater (communal, industrial and agricultural), is the worst. The situation with the
other river ecosystems (Bregalnitsa, Crna, Lepenets, Pchinya, Zletovitsa etc.) is similar.
Reservoirs have been built on some rivers, and these represent a sink for persistent
substances (e.g., Kalimanci and Tikvesh Lakes). The reservoirs which provide drinking
or industrial water (Mavrovitsa, Strezhevo, Turiya), although experiencing slight effects
from natural eutrophication, have experienced a deterioration in quality in past years due
to inappropriate fish stocking and exploitation. Benthic communities in the riverine
ecosystems are showing reduced abundance, which will ultimately lead to a decline in
fish populations. Six out of the 20 endemic fish species within the Republic of
Macedonia (Chondrostoma vardarense, Cobitis vardarensis, Gobio banarescui,
Pachychilon macedonicum, Salmo pelagonicus and S. peristericus) are found in riverine
ecosystems. Three of these are considered to be globally threatened species.
Wetland vegetation, which used to develop over large areas of swamps and marshes
within all the valleys of Macedonia, experienced great changes under past drainage
regimes which converted most of these ecosystems into arable land. In some of them,
(e.g., Monospitovo Marsh), numerous rare and endangered Algal taxa were formerly
found.
The relict wetland communities, which today appear mainly in a fragmentary state,
are the most endangered. They develop on organic soils which are very suitable for
growing early vegetable plants (Bansko) after drainage. Some which were present near
natural lakes have been destroyed simply because they represent unwelcome marsh
vegetation. The most important wetland communities still extant are: assn. Caricetum
elatae subassn. lysimachietosum (today only small fragments remain at Ohrid Lake near
Studenchishte) assn. Cypero-Caricetum acutiformis (Gostivar), assn. Glycerietum
maximae (Pelagonia - village Chepigovo), assn. Mariscetum (Negortsi Spa), assn.
Osmundo-Thelipteretum (Bansko), assn. Scirpo-Alopecuretum cretici (Monospitovo
Marsh) etc. Some of the wetlands which are still preserved are important in serving to
explain the genesis of wetland vegetation in the Republic of Macedonia.
Impacts to most of the swamps and marshes have caused a reduction in the
populations of all Amphibians, as well as individual species of other invertebrate and
vertebrate groups. The most affected are: Water vole (Arvicola terrestris), Eurasian
bittern (Botaurus stellaris), European pond terrapin (Emys orbicularis), Otter (Lutra
lutra), Balkan terrapin (Mauremys rivulata), Coypu (Myocastor coypus), Dice snake
(Natrix tessellata), Miller’s water shrew (Neomys anomalus), Water shrew (N. fodiens),
Muskrat (Ondatra zibethicus), Balkan spadefoot toad (Pelobates syriacus balcanicus),
Eurasian Spoonbill (Platalea leucorodia), Greek marsh frog (Rana balcanica), Balkan
stream frog (R. graeca), Marsh frog (R. ridibunda), Alpine newt (Triturus alpestris),