Distribution and Habitat Selection of Wintering Birds in the Special Protection Area ROSPA0071 Lower Siret Meadow (Eastern Romania)

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1 Travaux du Muséum National d Histoire Naturelle «Grigore Antipa» DOI: /travmu Vol. 58 (1 2) pp Research paper Distribution and Habitat Selection of Wintering Birds in the Special Protection Area ROSPA0071 Lower Siret Meadow (Eastern Romania) Matei Ionuț DRAGOMIR 1, 2, *, Adrian Cosmin STÎNGĂ 1, Alina DRAGOMIR 1 1 Association for Biological Diversity Conservation, 12 Ion Creangă street, Focșani, Romania 2 University of Bucharest, Faculty of Biology, Splaiul Independenței, Bucharest 5, Romania * corresponding author, e mail: matei.dragomir@acdb.ro Received: February 23, 2015; Accepted: April 04, 2016; Available online: April 15, 2016; Printed: April 25, 2016 Abstract. The ecosystems from the Special Protection Area ROSPA0071 Lower Siret Meadow (36492 ha, between Adjud city, Vrancea County and Şendreni village, Galaţi County) in the analysed sector (sixteen sample surfaces) present a scientific interest because of the geographical, ecological and biological characteristics. The paper treats details such as the number of individuals, the spatial distribution, availability of suitable habitats and threats, necessary data for the evaluation of the conservation status. We present the data obtained in the period from 64 field visits in the Special Protection Area ROSPA0071 Lower Siret Meadow, all made in the hiemal season. The observations were made as an activity of monitoring the protected bird species distribution and habitat selection of wintering populations. Five important sites were identified as being used by wintering birds here. During the monitoring actions, eighty one bird species were identified. The paper brings new data about the way birds use their range and existing habitats for wintering. Key words: wintering birds, monitoring, conservation, Lower Siret Meadow, Special Protection Area introduction The study was conducted following the centralization of data obtained from monitoring activities conducted in the Natura 2000 site ROSPA0071 Lower Siret Meadow. Existing studies in the literature are generally casual and mostly isolatedly made, the only data available is for Tălăbasca and Lozova lakes in Galați County (Arcan & Gache, 2008, 2010; Gache & Arcan, 2010) and old data from Biliești village in Vrancea county (Mihalciuc et al. 1976). The existing studies do not address the entire surface of the Lower Siret Meadow as a whole unit, and observations made in the hiemal season over several seasons are absent for the entire Natura 2000 site. The study area presents in certain sectors a high level of disturbance due to various human activities, and the human presence throughout the Lower Siret Meadow (fishing, recreation, economic activities etc.) determine changes in avian diversity and habitat use. Habitats encountered here underwent anthropogenic changes with a different degree of impact on avifauna. The most significant changes in the natural habitats are due to forestry and water management of the Siret river channel. The consequences of these changes of natural habitats are unclear due to the lack of studies made previously to human interventions and lack of information on the existing species ability to adapt to these specific changes. Since information about the avifauna that uses the area in the hiemal season is minimal, the main objective of the study was to supplement existing data and to

2 84 Matei Ionuț DRAGOMIR, Adrian Cosmin STÎNGĂ, Alina DRAGOMIR correlate the presence of birds with the habitat use and human impact. These data are useful for improving the management of the protected area, especially in the context of changing natural habitats with different human interventions. Understanding the factors that influence the presence and distribution of avifauna in an area is the premise to manage measures needed to improve and enhance the conservation status of species of conservation interest that use the area for winter. The main objectives have been to identify species wintering in the site and determine how they use the existing habitats. We also aimed to establish the populations in relative terms, data which will become initial values to which further monitoring will report. The study results and further winter monitoring activities can be used as tools for the management of the Natura 2000 site. material and methods The study was conducted in the Natura 2000 site ROSPA0071 Lower Siret Meadow during four consecutive hiemal seasons, between 2010 and The site area was divided into three major habitat types according to Corine Land Cover: wetlands, forests and farmlands. We made 48 field visits, targeting every type of habitat. Sample surfaces consisted of transects with a length of 1 km, selected from a stratified random selection. Each habitat type was divided into squares of 1 km 2, and for analysis being selected sixteen sample surfaces (Fig. 1): four agricultural areas, four forest areas and eight wetlands squares as in table 1 (more wetlands because most of the species of conservative interest are aquatic species). The studies were repeated on the same sample surfaces in different years ( ). The study period to which the dataset is reported to is November 1 st to March 1 st of each hiemal season. The collected data were centralized for the three major habitat types, differentiated using Corine Land Cover maps: Farmlands (FA), Forests (FO), Wetlands (WE). We analyzed the changes in the populations numbers and species identified in the same sample surfaces during four seasons. The time period is too short to establish a long term trend of bird populations numbers that use the area of ROSPA0071 in the hiemal season. We consider the data obtained as primary data to be used in assessing the long term conservation status of the species and their associated habitats. results and discussion Although we believe that the period to which the present study reports to is too short to illustrate a trend of the species population numbers, phenological results illustrate distribution of species in each month of the hiemal season. We can notice a difference in the number of species encountered in November (Fig. 2) due to the presence of some found in a late passage in the area, species wich were not encountered in the rest of the hiemal season like: Anas acuta Linnaeus, A. clypeata Linnaeus, Aythya ferina Linnaeus, Branta ruficollis Pallas, Gallinago gallinago Linnaeus, G. media Latham, Gavia arctica Linnaeus, Poecile palustris Linnaeus, Remiz pendulinus Linnaeus or Tadorna tadorna Linnaeus. Eighty one bird species were identified in the ROSPA0071 Lower Siret Meadow: one from Gaviiformes order, two Podicipediformes, two Suliformes, two Pelecaniformes, 17 Anseriformes, seven Falconiformes, two Galliformes, four Charadriiformes, two Columbiformes, two Strigiformes, one Coraciiformes, six Piciformes, 31 Passeriformes and two Gruiformes.

3 Distribution and Habitat Selection of Wintering Birds in Lower Siret Meadow 85 Fig. 1 Map of ROSPA0071 Lower Siret Meadow, major habitat types according to the Corine Land Cover maps, and the sample surfaces of this study.

4 86 Matei Ionuț DRAGOMIR, Adrian Cosmin STÎNGĂ, Alina DRAGOMIR Wetland (WE) Forests (FO) Farmlands (FA) WE1 confluence between a channel from the Berești Hydropower Plant and Siret River. Adjudul Vechi, FO1 mature oak forest. The transect intersects a marshy area with characteristic vegetation for NATURA E0* Alluvial forests with Alnus glutinosa and Fraxinus excelsior habitat type. Garoafa, FA1 crops; the transect is located between two forests (less than 200 meters away from both. Garoafa, Sample surfaces form the study area (numbered from North to South) WE2 Trotuș River, Salix alba, Populus alba young trees and Tamarix ramosissima shrubs. Adjud, WE3 confluence between Trotuș and Siret rivers. North side of the Călimănești Hydropower Plant reservoir with Phargmites sp. vegetation. Pufești, WE4 Siret River downstream Călimănești Hydropower Plant. The transect follows a high anthropogenic disturbance area with sand and gravel extractions and construction works for the future Cosmești Hydropower Plant. Mărășești, WE5 downstream from Movileni Hydropower Plant/seepage lake. Movileni, Galați County WE6 Tălăbasca Lake Natural Reserve. Tudor Vladimirescu, FO2 forest with characteristic vegetation for NATURA A0 Salix alba and Populus alba galleries habitat type. The transect is on the right side of Zătuan creek. Biliești, FO3 Robinia pseudoacacia plantation. Hanul Conachi Sand Dunes Natural Reserve, Fundeni, FO4 forest with characteristic vegetation for NATURA A0 Salix alba and Populus alba galleries habitat type. Braniștea, FA2 crops/ pasture; the transect is close to the Tălăbasca Lake Natural Reserve. Tudor Vladimirescu, FA3 crops. Tudor Vladimirescu, FA4 crops. Nămoloasa, WE7 Siret River, banks with hybrid poplar plantations. Tudor Vladimirescu, Galați County Table 1 WE8 Lozova Lake. Braniștea,

5 Distribution and Habitat Selection of Wintering Birds in Lower Siret Meadow November December January February Total number of species Species subject to the protection of ROSPA0071 Fig. 2 Species populations numbers in each of the hiemal season months. We note the presence of three Tadorna feruginea/cana hybrids in a seepage lake at Movileni, They were first encountered on 15 th of January 2014 and later on 23 rd of February 2014 in the same location. We also encountered other summer visitors in the hiemal season like: Podiceps cristatus Linnaeus in winter plumage on 2 nd of December 2012 at the Movileni artificial lake, Microcarbo pygmeus Pallas on 1 st of December 2013 in Lozova Lake Braniștea, Galați County, Aythya nyroca Güldenstädt also on 1 st of December 2013 in Lozova Lake Braniștea, Galați County, Phoenicurus phoenicurus Linnaeus on 29 th of December 2012 on the Movileni Hydropower Plant dam, Gallinula chloropus Linnaeus on 31 st of December 2013 at Ciușlea, Vrancea County, and Columba palumbus Linnaeus also on 31 st of December 2013 at Doaga, For the species under the protection of ROSPA0071 Lower Siret Meadow, the presence was graphically presented according to the months of the hiemal season, thus showing how they use the area during this period. It can be seen in fig. 3 that species like Anas acuta, Anas clypeata, Anas penelope Linnaeus, Aythya ferina or Tadorna tadorna occur only in November, basically the beginning of the hiemal season, period that may correspond to the autumn passage of related species. Other species like Aythya nyroca or Podiceps cristatus were seen also in December, but only until the lakes and ponds freeze, on Siret River there were no observations of these species. Most of the species encountered are those that can utilise a variety of aquatic habitats. Until the water from the lakes freeze, their presence is dispersed, using both the lakes (artificial or natural) and Siret River. In the artificial lakes of the hydropower plants Călimănești and Movileni, we note the presence of Anseriformes representants in large flocks, in December 2013 we estimate about 10,000 individuals in the Movileni artificial lake, most of them from Anas platyrhynchos Linnaeus species. After the lakes freeze, we identified three important concentration sites where water birds are grouped, all the sites have occured as a result of human intervention: 1. Confluence between a channel from the Berești Hydropower Plant and Siret River. Adjudul Vechi,

6 88 Matei Ionuț DRAGOMIR, Adrian Cosmin STÎNGĂ, Alina DRAGOMIR November December January February % 90% 80% 5, ,03 7,21 11,53 6,67 8,33 19,05 22,49 28,81 22,83 36,94 38,13 70% 60% 50% 40% 30% 20% 10% 0% ,97 76, ,67 28,57 22,83 37,9 17,27 14,29 48,31 34, ,39 33,7 41,67 38,1 33,99 22,88 28,84 30,22 20,65 5,62 13,33 8,33 Fig. 3 Presence of species subject to the protection of ROSPA0071 in each hiemal season month. The chart shows the ratio of total views and the presence in each month of the hiemal season. Vrancea County; 2. Confluence between Trotuș and Siret rivers, the North side of the Călimănești Hydropower Plant reservoir, Pufești Vrancea County; 3. Downstream from Movileni Hydropower Plant/seepage lake. Movileni, In these concentration sites we identified mixed flocks with as many as 3000 individuals (downstream of Movileni Hydropower Plant in January 2013). Most of the individuals were Anas platyrhynchos, but we also identified Cygnus cygnus Linnaeus, C. olor Gmelin, Anas crecca Linnaeus, Netta rufina Pallas, Aythya fuligula Linnaeus, A. marila Linnaeus, Bucephala clangula Linnaeus, Mergus merganser Linnaeus, Tachybaptus ruficollis Pallas, Fulica atra Linnaeus and gulls like Chroicocephalus ridibundus Linnaeus and Larus cachinnans Pallas. Regarding the fact that they are all grouped in very small areas (as low as 8 hectares in the seepage lake from Movileni), hunting reprezents a major impact factor, with victims from other species than the ones targeted by the hunters and disturbance to all of the wintering species present. For improving the conservation status of the species subject to the protection of ROSPA0071 Lower Siret meadow, it is mandatory to ban hunting in these small wintering concentration sites. We also identified two important wintering sites for Passeriformes and Piciformes species, one is the Black Forest Natural Reserve with mature oak forests and a marshy area with characteristic vegetation for Natura E0* Alluvial forests with Alnus glutinosa and Fraxinus excelsior habitat type in Garoafa, Vrancea County. Here we found Picus viridis Linnaeus, P. canus Gmelin, Dendrocopos major Linnaeus, D. minor Linnaeus, Dendrocopos medius Linnaeus and Dryocopus martius Linnaeus in all the hiemal seasons. The lack of human intervention in the forest structure makes it a habitat with favourable conditions for forest species. The second important forest habitat for wintering birds is Merișor Forest Natural Reserve, a forest with characteristic vegetation for Natura A0 Salix alba and Populus alba galleries habitat type. It is notable that a very small number of species

7 Distribution and Habitat Selection of Wintering Birds in Lower Siret Meadow 89 use the non native species forests with only Cyanistes caeruleus Linnaeus, Parus major Linnaeus and Fringilla coelebs Linnaeus found in hybrid poplar and Robinia pseudoacacia Linnaeus plantations. We have not identified any major difference between the habitat use of the farmlands by the avifauna (Fig. 4). Regarding the species subject to the protection of ROSPA0071 Lower Siret Meadow, Buteo buteo Linnaeus and Falco tinnunculus Linnaeus were found in all sampling surfaces and in all the survey period. In relation with major habitats types, as the study aimed to, fig. 5 shows the number of species according to each major type, most of the bird species are found in wetlands (44,44%) and as fig. 4 shows, the species subject to the protection of ROSPA0071 are encountered more in wetlands sample surfaces. The habitat use (Fig.6) presents an image of the differences in natural and semi natural habitats. The forest plantations with non native species represent the less suitable habitats for sustaining species diversity (only four species were found here compared to 28 species found in forests with native trees). Contrary to forest areas, wetlands greatest species diversity and also numerical abundance is found on the hydropower plants lakes Movileni and Călimănești. Remarks on species Regarding the protection objective of ROSPA0071 Lower Siret Meadow, we identified from the species listed in Annex I of Birds Directive: Alcedo atthis Linnaeus we found the species in all wetlands sample sites except WE8 Lozova Lake. We only saw a single individual at a time, except in FO2 sample surface on the Zătuan creek were we identified three individuals. Aythya nyroca we found one individual (male) on December 1st in WE8 Lozova Lake. Cygnus cygnus individuals were seen in every hiemal season between 2010 and 2014 in WE5 at Movileni Hydropower Plant. In 2012 we identified most FA1 FA2 FA3 FA4 FO1 FO2 FO3 FO4 WE1 WE2 WE3 WE4 WE5 WE6 WE7 WE8 Total number of species Species subject to the protection of ROSPA0071 Fig. 4 Total number of species per sample surface relative to the number of species of conservation interest.

8 90 Matei Ionuț DRAGOMIR, Adrian Cosmin STÎNGĂ, Alina DRAGOMIR 19; Farmlands 36; Wetlands 26; Forests Fig. 5 Number of species for each major habitat type. individuals, 170 from wich 38 juveniles. In 2014 we encountered the smallest group, only 67 individuals with 15 juveniles. Ardea alba Linnaeus the species was identified in all wetlands sample surfaces in the hiemal season. Its presence is constant in WE6 and WE8 until the water freeze and we identified individuals in most of the visits to WE5. In the rest of the wetlands sample surfaces the presence is irregular. We identified 7 15 individuals in each hiemal season. From the species that are not listed in Annex I of Birds Directive, but with a regular migration in the site, we encountered: Anas acuta we identified the species only two times in the hiemal season, three individuals in WE3 on 28th November 2011 and four individuals in WE8 17th November Anas clypeata its presence in hiemal season is not common in ROSPA0071, we encountered two individuals (male and female) in WE5 on 29th November Anas crecca common species in winter in ROSPA0071 Lower Siret Meadow, it appeared in all wetlands samples surfaces and in WE5 at Movileni dam and WE3 we saw flocks of about 2000 individuals in January 2011 and December Groups of more than 500 individuals were encountered on all lakes (except Lozova Lake) in all seasons until the water froze. In periods with frozen water, the species was identified in flocks of individuals in WE3 and WE5. Anas penelope the species was present in every month of the hiemal season in WE5, and WE3 with 50 to individuals. Until the water freeze, it was encountered also in WE6 and WE8, 30 to 50 individuals. Anas platyrhynchos from the species subject to protection of ROSPA0071, it has most individuals in the hiemal season, flocks of up to 10,000 individuals were encountered in WE5 in December In the period before the lakes water freeze, flocks of individuals were encountered each year in WE3 and WE5, smaller groups ( individuals) were identified in all wetlands sample plots.

9 Distribution and Habitat Selection of Wintering Birds in Lower Siret Meadow 91 Wetlands - natural lakes 17% Farmland 15% Forest - non native species 3% Wetlands - artificial reservoirs 20% Forest - native species 21% Wetlands - Trotuș river 8% Wetlands - Siret river 16% Farmland Forest - non native species Forest - native species Wetlands - Siret river Wetlands - Trotuș river Wetlands - artificial reservoirs Wetlands - natural lakes Fig. 6 Habitat use by the avifauna in ROSPA0071. Aythya ferina eight individuals were seen in WE6 in November 2011 and five individuals in WE in November Aythya fuligula rare sight in ROSPA0071, two adults (male and female) and one juvenile were seen in January 2013 and two individuals were seen in January 2014, both sights were made in WE1. Buteo buteo common sight in the farmlands of the Natura 2000 site, in each farmland sample surface were seen one two individuals in all hiemal seasons. Cygnus olor the species was identified in WE1, WE3, WE4, WE5, WE6 and WE8. Groups of up to 300 indivuduals are encountered each month of the hiemal season in WE5, in the rest of the sample sites, smaller 5 30 individuals are common sights. Falco tinnunculus just like the common buzzard, it is a common sight in the farmlands of the Natura 2000 site, in each farmland sample surface were seen one two individuals in all hiemal seasons. Fulica atra the species winters in ROSPA0071, it was found in WE1, WE3 and WE5 along entire season with groups of individuals, and in WE6 and WE8 in large flocks of up to 0 individuals until the water froze. Larus cachinnans the species was encountered in all wetlands sample surfaces. After the water froze, most of the individuals were seen in the nortern half of the site in WE1, WE3, WE4 and WE5. In most of the cases, we identified one to ten individuals. Phalacrocorax carbo Linnaeus common sight in the northern half of the site in the hiemal season, 5 30 individuals were identified in each visit in WE1, WE3, WE4, WE5, WE6, WE7 and WE8. In WE3, most of them were seen in one visit, 200 individuals in January In WE5, we also identified 150 individuals in December 2013.

10 92 Matei Ionuț DRAGOMIR, Adrian Cosmin STÎNGĂ, Alina DRAGOMIR Podiceps cristatus Only four individuals in winter plumage were seen on 2nd December 2012 in WE5. Tadorna tadorna only five individuals were seen in WE 6 in November 2012 Chroicocephalus ridibundus common sight in ROSPA0071, we mostly seen 1 20 individuals at one time, small numbers compared to serotinal and autumnal seasons, where flocks of up to 15,000 individuals were seen (Dragomir, unpublished data). references ARCAN, V., C. GACHE (2008) Phenology of the birds fauna from the Talabasca marsh (Galati county). Complexul muzeal de științele naturii Ion Borcea Bacău Studii și comunicări , 22: ARCAN, V., C. GACHE (2010) The bird fauna and the environmental changes in the lower Siret river (Galati county, România). Muzeul Olteniei Craiova Oltenia Studii și comunicãri Științele Naturii, 2: GACHE, C., V. ARCAN (2010) Rarities bird species in the lower meadow of Siret river SPA (Romania). Natura Montenegrina, Podgorica, 9: MIHALCIUC, M., M. TĂLPEANU, I. CĂTUNEANU (1976) Contributions a la connaissance de la faune du departement Vrancea. Travaux du Museum d Histoire Naturelle Grigore Antipa, 17: