Cover Page > Croat Med J. 2007;48:127-9

The Delta: Green Pearl of Coastal

The lower course of the Neretva river is a marshy widenings are not the result of erosive activity of valley. This bioecological complex is divided be- the river, but of tectonic predisposition (1). From tween two countries: the delta-shaped river mouth, then on, the material eroded in the upper course with the of Modro oko, Desne, and Kuti be- of Neretva has been depositing there, thus forming longs to Croatia, while the Nature Park of Huto- the today’s delta. vo blato belongs to Bosnia and . In The unique landscape and the specific culture many ways, the Neretva delta is different from oth- have made the Neretva delta an attraction for both er parts of coastal Croatia. Its unique landscape is a Croatian and international tourists. However, this result of digging and depositing of the marsh soil, has not always been the case. In the eighteenth cen- so-called “jendečenje.” Furthermore, Neretva is the tury, this region was beset by fever that grew par- only river in this region with a delta at its mouth. ticularly strong in autumn. The Padua professor At the same time, it is also the area of the most in- and physician Giuseppe Pujati termed it neretljan- tense man-made landscape transformation. In spite ska bolest (the Neretva disease) in his treatise De of the conversion of wilderness into tamed waters morbo Naroniano (On the Neretva disease) (2). and arable land, the landscape around the Neretva For the fear of contagion with a disease of an un- delta has preserved its beauty and romance. The al- known cause and treatment, sailors who accompa- luvial plains in the carst setting have become both nied Alberto Fortis on his voyage to Dalmatia at the inspiration for artists and a topic of scientific first refused to travel to this region. Pujati believed research. the disease to be a kind of plague, from which one In the Pleistocene, the region around the pres- could hardly be saved. He described it in the fol- ent river mouth of Neretva looked significantly dif- lowing way: “The water that stagnates at certain ferent. It was occupied by the then middle course places becomes so pestiferous that it kills the fish of the Neretva river, the bed of which stretched that swims in it; marsh birds that live there in large along the today’s peninsula of Pelješac. The river numbers often fall down poisoned by lethal evap- flew into the sea in the proximity of today’s town orations.” It is debatable if these birds died from of Vela on the island of Korčula. With the bird malaria. At the same time, Fortis’ observation end of the ice age, the sea level rose about 100 m, raised suspicion of the prevalence of human, mos- which resulted in shortening of the river and for- quito-transmitted malaria in this area (2): “Each mation of a new mouth, situated approximately inhabitant of the region has a small tent as a pro- at the location of the present river mouth and in tection from mosquitoes and related insects dur- the proximity of three triangular widenings. These ing sleep… A priest once told me that he suspected

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the fevers troubling them were caused by insect explored. This greatly hinders an accurate assess- bites, because after these insects had sucked the ment and protection of this highly endangered blood of fish, dead four-legged animals, or nox- region. It is particularly worrisome that the ex- ious herbs, they came to suck people’s blood.” It tensive melioration, which took place about is known today that the Balkans once had Pan- thirty years ago with the financial support of the nonic and Mediterranean malaria zones, and that Food and Agriculture Organization (FAO), was the regions of Istria-Kvarner, Zadar, and Neret- conducted in the absence of any biological-eco- va were the foci of malaria in the coastal Croa- logical studies. As a result, a significant propor- tia (3). Today the Neretva region, as well as oth- tion of the area has been completely transformed er parts of Croatia, are free from this disease. It, from into agricultural land. At the same however, continues to be widespread worldwide; time, the protection of nature was not taken into according to 2002 estimates, there were half a account. billion cases of the lethal form of malaria in the The most significant transformation of the world, which is 50% more than the estimates of delta took place in the recent decades with the in- the World Health Organization (4). tense and long-term melioration, the purpose of In the past, Neretva delta was not only well which was to create agricultural land and to pro- known because of malaria, but also because of tect the region from floods. A significant assault the abundance and diversity of bird and fish fau- on the marshes was the drainage of Modrič na, as well as by the activities of hunting and fish- and the entire lagoon. A large part of the wetland ing, partaken by almost all inhabitants of the re- was thus lost for migrating birds and spawning gion. Dense marshlands were overgrown with fish. The further expansion of the port and set- hydrophilic vegetation, which provided excel- tlement of Ploče, building of holiday homes, in- lent conditions for fish spawning and bird nest- dustry, and the pollution of water from ing. This explains why this region was in the past and other sources, still endangers marshy valleys a home to various species of herons, cormorants, of the Neretva river. ducks, and other water-birds, as well as colonies An important problem in this region is bird of the today regionally extinct species of Dalma- hunting, which is a part of traditional culture tian pelicans, Pelecanus crispus. In that period, and customs. Ćukanje, a specific method of Neretva branched into 8 armlets near the town hunting the coot (Fulica atra), resulted in almost of and made a wide delta; Opuzen itself complete extinction of this species of bird. There was located on the island of Posrednica. Over the is also illegal hunting of other species of wild last 100 years, 310 bird species, out of which 115 birds. In addition to the loss of fauna component were breeding birds, were registered in this re- of the wetland ecosystem, hunting is also accom- gion. Around 35 species are water-birds (5). The panied by emission of various pollutants into the Central and Northeastern European bird pop- ground and water. This aggravates the life quality ulations used the delta for wintering. The shal- of the human population and has a negative ef- lows and shoals of the Neretva river mouth were fect on the flora and fauna. The current state of of great importance for the migration of waders, bird fauna in the Neretva valley requires a thor- terns, and gulls, and so were reed beds and water ough assessment and a change of the entire bird- surfaces for the migration and wintering of geese wetland-humans relationship. and ducks. It is a contradiction of the Neretva delta Although the region of Neretva delta has al- that this region, although highly endangered, is ways had an extraordinary biological and ecolog- a home to many protected “objects of nature.” ical importance, it is still relatively insufficiently Protected areas occupy the surface of 1624 hect-

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ares (13% of the entire region) and are grouped cultural areas, by some perceived as neglected, into five protection categories: ornithological have reverted to the old natural state and imme- and ichthyological-ornithological reserves, “Hor- diately started to attract birds and fish. The rest ticultural Monument-Tree,” Significant Land- of the area is cultivated land in the square form, scape, and Park Forest. The ornithological re- sown with modern commercial crops. Agrarian serves Orepak (100 hectares), Podgrede (587 cultures between the marshlands give the area a hectares), and Prud (250 hectares) are the rem- green visual identity and make it different from nants of the Mediterranean wetland crucial for the rest of the coast. This is why the Neretva del- the bird migration and wintering. The south- ta is called the green pearl of the southern Croa- eastern part of the Neretva delta is an ichthy- tian coast. ological-ornithological reserve (250 hectares) In spite of the large-scale disturbance of birds, where fish spawn and birds arrive in the periods as well as the destruction and degradation of wet- of migration and wintering, with some of them land in the past and today (6), the delta of Neret- breeding there. In Metković, cypress (Cupresus va still presents a biologically valuable area. There sempervirens var pyramidalis) is protected as a is a diversity of landscapes and , such as “Horticultural Monument – Tree.” Modro oko streams, rivers, lakes, marshes, and numerous and the lake Desne (370 hectares) are protected springs. There are both natural and man-made within the “Significant Landscape” category, be- biotopes: meadows, agriculture land, numerous cause of their features characteristic of the low- channels (jendeci), dams, and settlements con- er course of Neretva. These include alluvial carst nected by roads. There are proposals to include depression with an abundance of water and wet- the Neretva delta and its population into a future land biotopes. Predolac – Šibanica (67 hectares) Nature Park to protect it from further devasta- is the protected area east of Metković in the Park tion. The protection of natural resources should Forest category, which includes aleppo pine and be combined with the needs of further develop- Mediterranean cypress with macchia elements. ment and it should take into account regional The list of specially protected objects of na- traditions. ture, composed in 1991 by the Ministry of En- Jasmina Mužinić vironment, does not mention the protected re- [email protected] gions of the municipality of Ploče. These are Parila (410 hectares), Baćinska lakes (286 hect- References 1 Todorović B. The Neretva delta – from wetland to intensive ares), and part of the region around Modro oko agriculture [in Croatian]. Available at: http://www. (145 hectares). Furthermore, the list does not geografija.hr/novosti.asp?id_novosti=626&id_projekta=0 include the area of the lake Kuti (ornithologi- &trazi=neretva. Accessed: March 5, 2007. 2 Fortis A. A voyage through Dalmatia [In Croatian]. Split: cal reserve, 490 hectares), because of the lack of Slobodna Dalmacija; 2004. agreement between conservationists and the lo- 3 Malaria. In: Šercer A, Grmek MD, editors. Medical enciclopedia, part 4 [in Croatian]. Zagreb: Jugoslavenski cal businesses. The Kuti area combines wetland, leksikografski zavod; 1969. p. 374-80. lakes, and carst landscape, and is abundant with 4 Bad news [in Croatian]. Jutarnji list. 2005 March 11; p. 88. marshland vegetation and freshwater fish, in par- 5 Mrakovčić M. Identification of relationship between hydrological dynamics and biodiversity values of the ticular eel. Numerous strong streams supply the Neretva [in Croatian]. Zagreb: Regional Center for Environment Protection in Middle and Eastern Europe area with water. (REC – office in Croatia); 2001. A document in possession Today, the region of the Neretva delta is sub- of author. jected to agricultural exploitation, but the drain- 6 Mužinić J. Neretva valley – threatened area in Croatia [in Croatian]. Proceedings of the fourth congress of Croatian ing of wetland is less intense. The deserted agri- biologists. Zagreb: Croatian biological society; 1993.

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