FAUNA AND FLORA IN THE BALTIC SEA

Prepared by the teacher of Biology R. Aglinskiene and 9th grade pupils

• Every species, living in the Baltic Sea, are the descendants of various evolution periods: Ice Lake and Arctic Sea relics, North Atlantic immigrants.

• Biologic variety in the Baltic Sea is small, because the water is too fresh for many marine species and to saline for freshwater species.

At the moment there are about 6 thousand known species in the Baltic Sea, 4,7% of which are marine birds and mammals. Their life is sustained by comparatively small organisms freely floating in the water column, called Plankton (They comprise 44% of the known species) or plants and animals living on the bottom of the sea, called Benthos (comprising 51% of known species).

Aquatic organisms

The Lithuanian coast is dominated by copepods— the saline water is usually abundant with the representatives of Mesocyclops or Thermocyclops groups and the diffusion zone of the curonian spit waters by freshwater Pseudocalanus minutus or Acartia longiremis.

Fauna and Flora in the bottom of the sea

• There are more than 50 bottom invertebrate species found on the coast, almost half (22species) of which are crustaceans, freely swimming on the bottom water layer. The most common species are Mussel (Mytilus elidus), Baltic macoma (Macoma Balthica) and Barnacle crustaceans (Balanus improvisus).

Birds

• There are regularly found up to 30 different bird species on the Lithuanian coast. The most abundant, regularly seen and important to the environment are the ones hibernating in the basin of the Baltic sea representatives: long-tailed Duck (Clangula hyemalis) and Velvet scoter.

Fishes

• There are 65 registered species of fishes in the Lithuanian waters of Baltic Sea, 21 of which are freshwater, 33 marine and 11 migrating. Baltic herring (Clupea harengus membras), Baltic cod (Gadus morhua callarias) and flounder (Platichthys flesus)— some of the best fishes in the Lithuanian economy zone.

Gadus morhua callarias

Platichthys flesus

Mammals

• There are 5 species in the list of Baltic Sea mammals, which are constantly seen on the coast or in the sea. 3 of which belong to the pinnipeds (Grey Halichoerus grypus), Pusa hispida and South Atlantic simple Phoca vitulina vitulina), and one guinea pig Phocoena phocoena of the whale family.

Phocoena phocoena Halichoerus grypus