SILIŞTIOARA MARSH POTENTIAL IMPORTANT BIRD AREA

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1 Analele Ştiinţifice ale Universităţii AL. I. CUZA Iaşi, s. Biologie animală, Tom LII, 2006 SILIŞTIOARA MARSH POTENTIAL IMPORTANT BIRD AREA NARCISA ORZAŢĂ University of Craiova, Str. Al. I. Cuza 13, Craiova, Romania; Abstract. The Siliştioara Marsh, located on the outskirts of Corabia, on the Danube border, is one of the few marshes remaining in the Danube valley between the Rivers Jiu and Olt. The marsh is an important resting place, visited by numerous passage visitor bird species and also by bird species that nest here or in the adjacent areas. The vast majority of these are included in the local and global protection and conservation plans. The purpose of this paper is to present the area s bird fauna spectrum, in order to declare it Important Bird Area (I.B.A). Keywords: Siliştioara Marsh, Danube Meadow, Important Bird Area, bird fauna Rezumat. Balta Siliştioara potenţială Arie de Importanţă Avifaunistică. Balta Siliştioara, situaţă în imediata vecinătate a localităţii Corabia, pe malul Dunării, este una dintre ultimele bălţi naturale existente în lungul văii Dunării între văile râurilor Jiu şi Olt. Adăpostind un număr total de cel puţin 106 specii de păsări inventariate până în present, balta reprezintă un important loc de refugiu pentru păsări fiind vizitată de numeroase specii în pasaj; totodată, balta Siliştioara constituie arie de cuibărit pentru păsări acavtice şi semiacvatice, majoritatea fiind incluse în anexele unor convenţii internaţionale şi legi prvind protecţia speciilor şi a habitatelor în care acestea trăiesc. Dintre speciile de păsări înregistrate de noi, 86 constituie criteriu pentru desemnarea Ariilor de Importanţă Avifaunistică (A.I.A.). Cuvinte cheie: Balta Siliştioara, lunca Dunării, Arie de Importanţă Avifaunistică, avifaună Introduction Siliştioara Marsh is perhaps the only marsh left in the Danube meadow between the Rivers Jiu and Olt, after there were achieved important hydrotechnics arrangements and improvement actions for the decrease of the flood risk and also for the enlargement of the agricultural areas, in the 60s and 70s. The marsh is located on the outskirts of the town of Corabia, on the Danube banks, right below the first terrace, at about meters from the road. Although it isn't a large body of water, it continues eastwards (in Gârcov village) in a stretch of m of reed and club rush (100 hectares). The marsh has its own springs, but the water level is influenced by the Danube, as well as by rainfall. Water depth is of about 0.5 m. The southern part of the marsh consists of pastures, which are partially wet, and are used by local people for grazing. There is no protection dyke in the area, and the tree cordon is a bit further away. In front of the marsh, on the Danube, there is the Băloi Islet (200 ha), covered by riverside coppices of willow, acacia and poplar trees. Around the marsh, especially on the southern bank, but also in the marsh itself, there is rich paludous vegetation. The marsh has not been studied before 2002 (Orzaţă, 2002) and the bird fauna observation have been done during the period These allow us to conclude that the marsh and its neighbouring areas are populated by numerous bird species, especially during migration periods and during the nesting periods, too. Material and Methods Ornithological observations were taken during , covering the all phenological aspects. The methods used were the transect method and the observation from fixed point, the identification of the birds being made by direct observations with the

2 Narcisa Orzaţă 10x50 binoculars. Transects and observation points were established from the first visits and were kept for the entire period of study. The census of bird populations was done by direct counting of all observed individuals. Results and Discussion This paper analyzes the bird fauna spectrum of the Siliştioara Marsh from the Danube Meadow, in Olt County, and the status of the identified species, with the purpose of including this area on the list of Romanian Important Bird Areas. During the four years of observations (Orzaţă, 2002, 2002a, 2003, 2003a, 2005, 2005a), 106 species have been identified in this area (Table 1), belonging to 12 orders and 34 families. Aquatic and semi-aquatic bird species of the Ciconiiformes Order have a strong presence (12 species), as do those of the Anseriformes Order (15 species) and Charadriiformes Order (26 species). Best represented are birds from the Passeriformes Order with 31 species (29.24% of whole recorded bird fauna), belonging to 10 families. It is certain that inside or nearby the marsh (especially on the Băloi Islet), the following bird species are breeding: the Mallard Duck (Anas platyrhynchos), the Garganey (Anas querquedula), the Grey Heron (Ardea cinerea), the Little Bittern (Ixobrychus minutus), the Night Heron (Nycticorax nycticorax), the Eurasian Coot (Fulica atra), the Common Moorhen (Gallinula chloropus), the Lapwing (Vanellus vanellus), the Black-winged Stilt (Himantopus himantopus), the Little Tern (Sterna albifrons), warbler species (Acrocephalus sp.), the Savi' s Warbler (Locustella luscinioides), the European Bee-eater (Merops apiaster), but the number of breeding pairs is not large. One of the possible causes is the location of the marsh in the vicinity of the town of Corabia (the Siliştioara neighbourhood). In the area, the birds are permanently confronted with the pressure of several perturbing factors: fishing, grazing, reed burning and harvesting, and the presence of domestic animals. Aquatic bird species react differently by behavioural changes of their life regime: leaving the marshes area, renouncing breeding in the perimeter of a particular marsh, reducing their activities to certain parts of the aquatic basin. During summer time numerous birds have been observed, but the majority do not breed there: the Great Cormorant (Phalacrocorax carbo), the Purple Heron (Ardea purpurea), the Eurasian Spoonbill (Platalea leucorodia), the Little Egret (Egretta garzetta), the Mute Swan (Cygnus olor), terns and seagull species. During spring and autumn, have been noted the presence of duck species (Anas penelope, Anas clypeata, Anas acuta), shorebirds (Tringa sp., Numenius arquata, Calidris sp., Gallinago gallinago), this area being an important resting place for these species during migration period. We recorded 86 bird species that represent IBA criteria using to identify Important Bird Area (81.13% from the whole bird fauna). These species belong to the following IBA criteria (table 1): A1 4 species of global conservation concern (4.65%): Phalacrocorax pygmaeus, Pelecanus crispus, Anser erythropus, Aythya nyroca. Its entire have been observed while passing in the area. Pelecanus crispus became a constant presence in the area during the last years ( a single individual; single individual; February 2004 maximum 31 individuals; individuals). Phalocrocorax pygmaeus was noted during passage period, with few numbers. Aythya nyroca could have been breeding in the area during the summer of A3 5 biome-restricted species (5.81%): Anser albifrons, Calidris temminckii, Tringa erytropus, Tringa nebularia, Fringilla montifringilla. These birds pass through there, finding optimal conditions for feeding and resting. Anser albifrons was observed only once (2 individuals) on March 9 th The shorebird species (Calidris sp. and

3 Analele Ştiinţifice ale Universităţii AL. I. CUZA Iaşi, s. Biologie animală, Tom LII, 2006 Tringa sp.) appear during passage in numbers of tens of individuals. Fringilla montifringilla was observed in the winter of A4/B1 60 gregarious species (69.77%) are represented by aquatic and semiaquatic species (Phalacrocorax carbo sinensis, Pelecanus onocrotalus, Ardea cinerea, Egretta alba, E. garzetta, Ciconia nigra, Plegadis falcinellus, Platalea leucorodia, species of the Anseriformes, Gruiformes and Charadriiformes Orders), or connected to aquatic environments (Riparia riparia, Merops apiaster), as well as species of raptors (Falconiformes Order). The Great Cormorant (Phalocrocorax carbo sinensis) does not breed in the area, but some individuals stop and feed often in the marsh. The Great White Pelican (Pelecanus onocrotalus) was observed only once, on November 1 st 2003 (two individuals). Ardea cinerea breeds next to the Egretta garzetta in the marsh forest, staying and feeding in the area. Egretta alba stays even during winter time (maximum 15 individuals), together with Ardea cinerea. The Glossy Ibis (Plegadis falcinellus) is a passage species, the largest number of individuals observed being 37, on April 14 th The Spoonbill (Platalea leucorodia) was frequently seen in the area, between April and October 2002, with a peak population of 57 adult and juvenile individuals in July-August 2002, and from March in 2003 until the end of September that year, breeding probably in the Băloiu Islet and often crossing the Danube into Siliştioara Marsh. In 2004, the maximal number was recorded on July 15 th Most of the Anseriformes of this category are passage species, as breeding species we noticed the Anas platyrhynchos and Anas querquedula, and like probably breeding species the Anas strepera and Aythya ferina. The Common Teal (Anas crecca) is a winter visitor, present from autumn time (October) till spring (March), with effectives about individuals. The Common Coot (Fulica atra) breeds in the Siliştioara Marsh with about 30 pairs. The Common Moorhen (Gallinula chloropus) is a regular breeding species, but it effective was not estimated. Like breeding limicoline bird species have been noticed Himantopus himantopus, Charadrius dubius, Vanellus vanellus and also the Little Tern (Sterna albifrons), but not in very large numbers (10-20 pairs for each of them), most of the limicoline birds being passage species in the marsh perimeter. B2 31 species with an unfavourable conservation status in Europe (36.05%). From these species, the area is a nesting place for Ixobrychus minutus, Ciconia ciconia (7 nests counted in town, two of these in the neighbourhood adjacent to the marsh), Chlidonias hybridus (observed on the nest in 2004 and 2005, Merops apiaster (its nests located in the high bank on the left of the marsh), Riparia riparia (in , there was a colony about several hundreds individuals in the Danube bank, which was destroyed in the following years due the high levels of the river and flooding, only few nests being reconstructed in the high bank after this moment), Hirundo rustica, Lanius sp. B3 12 species with favourable conservation status in Europe (13.95%) aquatic and semi-aquatic species like Aythya ferina, Porzana parva, Recurvirostra avosetta, and also passerines: Locustella luscinioides, Acrocephalus schoenobaenus, Acrocephalus scirpaceus, Corvus monedula, Fringilla montifringilla, Carduelis chloris, Miliaria calandra, Emberiza citrinella and Emberiza schoeniclus. By consulting the Red List of Vertebrates in Romania (Botnariuc & Tatole, 2005), it results that 21 of the species identified on the Siliştioara Marsh are included on the list, as vulnerable or endangered species. The human pressure in the area is determined largely by intensive grazing and the presence of small size livestock (ducks, geese). Also in the area is practiced individual fishing, both on the marsh and on the Danube banks. Reed is cut and used in households, or is even burned down (Orzaţă, 2005)

4 Narcisa Orzaţă Table 1. Avifauna of the Siliştioara Marsh (Olt county). SPECIES RED IBA CATEGORIES LIST A1 A3 A4/B1 B2 B3 Phalacrocorax carbo sinensis (L) * Phalacrocorax pygmaeus (Pall) * * * Pelecanus onocrotalus(l) * * Pelecanus crispus (Bruch) * * * Botaurus stellaris (L) * Ixobrychus minutus (L) * Nycticorax nycticorax (L) * * * Ardeola ralloides (Scop) * * * Egretta garzetta (L) * * Egretta alba (L) * * Ardea cinerea (L) * Ardea purpurea (L) * * Ciconia nigra (L) * * Ciconia ciconia (L) * * * Plegadis falcinellus (L) * * Platalea leucorodia (L) * * Cygnus olor (Gmel) * Cygnus cygnus (L) * Anser albifrons (Scop) * * Anser erythropus (L) * * Anser anser (L) * Tadorna tadorna (L) * * Anas penelope (L) * Anas strepera (L) * Anas crecca (L) * Anas platyrhynchos (L) * Anas acuta (L) * Anas querquedula (L) * Anas clypeata (L) * Aythya ferina (L) * * Aythya nyroca (Guldenst) * * * Circus aeruginosus (L) * Accipiter nisus (L) Buteo buteo (L) * Falco tinnunculus (L) * * Falco subbuteo (L) * Perdix perdix (L) * Phasianus colchicus (L) Porzana parva (Scop) * Gallinula chloropus (L) * Fulica atra (L) * Haematopus ostralegus (L) * * Himantopus himantopus (L) * * Recurvirostra avosetta (L) * * * * Glareola pratincola (L) * * Charadrius dubius (Scop) * Vanellus vanellus(l) * Calidris temminckii (Leisl) * * Calidris ferruginea (Pontopp) * * Philomachus pugnax (L) * * Gallinago gallinago (L) * Limosa limosa (L) * Numenius arquata (L) * *

5 Analele Ştiinţifice ale Universităţii AL. I. CUZA Iaşi, s. Biologie animală, Tom LII, 2006 Tringa erytropus (Pall) * * Tringa totanus (L) * * Tringa nebularia (Gunn) * * Tringa ochropus (L) * Tringa glareola (L) * * Actitis hypoleucos (L) * Larus minutus (Pall) * * Larus ridibundus(l) * Larus canus (L) * * Larus argentatus (Pall) * Sterna hirundo (L) * * Sterna albifrons (Pall) * * Chlidonias hybridus (Pall) * * Chlidonias niger (L) * * Columba livia domestica Streptopelia decaocto (Friv) Cuculus canorus (L) Athene noctua (Scop) * Alcedo atthis (L) * Merops apiaster (L) * * Coracias garrulus (L) * Upupa epops (L) * Galerida cristata (L) * Alauda arvensis (L) * Riparia riparia (L) * * Hirundo rustica (L) * Delichon urbica (L) Anthus campestris (L) * Motacilla flava flava (L) Motacilla flava feldegg Motacilla alba (L) Locustella luscinioides (Savi) * Locustella naevia (Bodd) Acrocephalus schoenobaenus (L) * Acrocephalus scirpaceus (Herm) * Acrocephalus arundinaceus (L) Phylloscopus collybita (Vieil) Lanius collurio (L) * Lanius minor (Gmel) * Garrulus glandarius (L) Pica pica (L) Corvus monedula (L) * Corvus frugilegus (L) Corvus corone cornix (L) Sturnus vulgaris (L) Passer domesticus (L) Passer montanus (L) Fringilla montifringilla (L) * Carduelis chloris (L) * Carduelis carduelis (L) Miliaria calandra (L) * Emberiza citrinella (L) * Emberiza schoeniclus (L) * TOTAL:

6 Narcisa Orzaţă Conclusions Siliştioara Marsh is one of the last marshes remaining in the Danube Meadow between the Rivers Jiu and Olt, an unprotected area where the human factors influence the repartition, biology and ecology of birds present there. The bird fauna of the Siliştioara Marsh is represented by 106 species belonging to 12 orders. 86 of the species are representative criteria for identifying important bird areas, which means 81.13% of the whole identified bird fauna. According to the Red List of Vertebrates in Romania, 21 species present here are included in this list as endangered and vulnerable, both locally as well as globally. For these reasons, we propose this area to be included or at least considered for inclusion on the list of Romanian Important Bird Areas, its bird fauna spectrum being rich and representative for this purpose. References Botnariuc N., Tatole V., Cartea Roşie a vertebratelor din România. Academia Română, Muzeul Naţional de Istorie Naturală Grigore Antipa, Bucureşti. Orzaţă, N., Contribuţii la cunoaşterea avifaunei din zona Corabia-Siliştioara. Analele Banatului, s. nouă, Ştiinţele Naturii, I: Orzaţă, N., 2002a. Contribuţii la cunoaşterea avifaunei din zona Corabia-Siliştioara (II). Oltenia, Studii şi comunicări, Ştiinţele Naturii, XVIII: Orzaţă, N., Rare, vulnerable and endangered birds in Danube Meadow between the rivers Jiu and Olt. Analele Universităţii din Craiova, s. Biologie, Horticultură, Tehnologia prelucrării produselor agricole, VIII(XLIV): Orzaţă, N., 2003a. Pasările acvatice din Lunca Dunării dintre Jiu şi Olt. Oltenia, Studii şi comunicări, Ştiinţele Naturii, XIX: Orzaţă N., Actual Anthropic Influences and Alterations in the Avifauna Caused by Disappearance of Natural Wet Areas of the Danube Meadow. Analele Universităţii din Craiova, s. Biologie, Horticultură, Tehnologia prelucrării produselor agricole, X(XLVI): Orzaţă N., 2005a. Starea actuală a avifaunei din Lunca Dunării dintre Jiu şi Olt. Oltenia, Studii şi comunicări, Ştiinţele Naturii, XXI: ***, Buletin A.I.A. Buletin informativ asupra ariilor de importanţă avifaunistică din România,