Scientific Annals of the Danube Delta Institute, 2019
In the period 2003-2006, a series of bird markings were performed in nesting colonies from the no... more In the period 2003-2006, a series of bird markings were performed in nesting colonies from the northern part of the Sinoie lagoon in the Danube Delta Biosphere Reserve. We marked with colour plastic and metal rings nestlings of breeding species as Dalmatian Pelican (Pelecanus crispus Bruch, 1832), Great Cormorant (Phalacrocorax carbo Linnaeus, 1758) and the Eurasian Spoonbill (Platalea leucorodia Linnaeus, 1758). We already published a series of preliminary results for Great Cormorant and the Eurasian Spoonbill (Kiss et al., 2007; Sándor et al., 2009), here we follow the publishing of recoveries received after 2009. This paper contains the results obtained after this date, integrating the information obtained from the other marked species, the Dalmatian Pelican, which was not previously discussed. At the same time, for a better interpretation of the results, a brief summary of the results from the previous phase is made.
BSTRACT. The European mink (Mustela lutreola L.) is critically endangered. The Danube Delta Biosp... more BSTRACT. The European mink (Mustela lutreola L.) is critically endangered. The Danube Delta Biosphere Reserve (DDBR) is one of the last refuges of this species. Within the DDBR the European mink is still widespread as indicated by 74 life captures in a number of expeditions between 2003 and 2011. No American mink (Neovison vison), a serious threat to the European mink, were trapped or observed during 2000 and 2011 in the DDBR. Trapping success varied both between years and between trapping areas, but up to know the underlying factors for these patterns are not understood. It may be a combination of generally changing mink densities in the Delta due to food availability or reproduction success and habitat quality as a local factor. In this context we discuss potential limiting factors and outline some aspects for a future management plan of the species.
In the context of climate change, globalization, and enhanced human traveling, arboviruses contin... more In the context of climate change, globalization, and enhanced human traveling, arboviruses continue to represent a threat to public health. West Nile and Usutu viruses are mosquito-borne viruses belonging to the Flaviviridae family (Flavivirus genus) and members of the Japanese encephalitis virus serocomplex. Included in the Togaviridae family (Alphavirus genus), the Sindbis virus is also vectored by mosquitoes. In the present study, we aimed to analyze the presence of antibodies concerning the abovementioned viruses in migratory and resident birds in the South-Eastern region of Romania, as avian hosts represent the main reservoir for human infection. Blood samples were collected from wild birds between May 2018 and October 2019 in nine locations from three counties. All the samples were serologically tested by ELISA and a serum neutralization test. Overall, a seroprevalence of 8.72% was registered for the West Nile virus, 2.71% for the Usutu virus, and 0% for the Sindbis virus. To ...
Additional file 2: Table S2. Records of the climatic parameters for each day of the sampling peri... more Additional file 2: Table S2. Records of the climatic parameters for each day of the sampling period included in the current study.
According to historical records, in the early twentieth century the Glossy Ibis was a common spec... more According to historical records, in the early twentieth century the Glossy Ibis was a common species in all the main wetlands of southern and eastern part of Romania. Due to habitat degradation and loss throughout the Danube floodplain and its main tributaries the breeding population underwent a dramatic decline, some colonies disappeared while others suffered considerable numerical decrease. At that time, the Danube Delta was considered to be the main refuge for the species in Romania which registered a maximum of 12,000 pairs in 1977 followed by a sharp decline to about 6,000 in 1979 and 525 in 1983. In the 1984-1995 period the population increased to 3,340 pairs and varied between 2000 – 3000 breeding pairs during the next decade. Although all known Glossy Ibis colonies from Romania are located in protected areas and have a good conservation status, recent annual surveys show large fluctuations in breeding population size. Whereas historical fluctuations have been mostly attribut...
Background In a countrywide study aiming to update the knowledge on diversity of sand fly species... more Background In a countrywide study aiming to update the knowledge on diversity of sand fly species in Romania, a sand fly population was observed in an isolated system of cave microhabitats. The caves are located in the protected area of Canaraua Fetii, Dobrogea region, southeastern Romania. The highest sand fly diversity was recorded in this area between 1968 and 1970. This work presents a study conducted to estimate the seasonal variation of the sand fly species in correlation with the particular environmental factors of the isolated system of cave microhabitats. Methods Sand flies were collected between May and October 2020 from one trapping site of interest in Canaraua Fetii. The trapping site consisted of a cave entrance. CDC miniature light traps and sticky traps were used to collect insects from the exterior walls of the cave entrance. Species identification of collected sand flies was done using morphological keys. Statistical analysis of the trapping and climatic data was pe...
Between 1931 and 2018 in the Danube Delta, 1,171 Great White Pelican (Pelecanus onocrotalus Linna... more Between 1931 and 2018 in the Danube Delta, 1,171 Great White Pelican (Pelecanus onocrotalus Linnaeus 1758) were ringed (731 with metal rings, 440 with coloured plastic rings) at breeding sites. The majority of the captured birds were flightless young individuals. From the ringed birds, 25 (2.13%) were reported as recaptured. Most were reported from Israel (28%), and the rest from 8 other countries. Recovery distance varied between 50 and 3,000 km. 19 birds (76%) were reported within half year after ringing, 2 birds (8%) within a year, and further 4 individuals (16%) were reported after a year. With the exception of a single photographed individual, all the others perished: they were shot or fell victims to accidents. These cases suggest high mortality in the young age cohort. Very little knowledge is available about the African wintering grounds; there are only two reports from Egypt and one from Southern Sudan. Traditional ringing yields little information for this species. Conside...
West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild b... more West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild birds as amplifying hosts and ornithophilic mosquito vectors. Bridge vectors can transmit WNV to mammal species potentially causing West Nile Fever. Wild bird migration is a mode of WNV introduction into new areas. The Danube Delta Biosphere Reserve (DDBR) is a major stopover of wild birds migrating between Europe and Africa. The aim of this study was to investigate the presence of WNV in the DDBR during the 2016 transmission season in wild birds and mosquitoes. Blood from 68 wild birds (nine different species) trapped at four different locations was analyzed by competitive ELISA and Virus Neutralization Test (VNT), revealing positive results in 8/68 (11.8%) of the wild birds by ELISA of which six samples (three from juvenile birds) were confirmed seropositive by VNT. Mosquitoes (n = 6523, 5 genera) were trapped with CDC Mini Light traps at two locations and in one location resting mosqui...
A number of faunistically interesting observations related to the avifauna of the Danube Delta (R... more A number of faunistically interesting observations related to the avifauna of the Danube Delta (Romania) are presented. In the spring of 2015, a mass mortality event with a minimum of 118 dead birds occurred in a major Dalmatian Pelican Pelecanus crispus colony in the Black Sea lagoons caused by the avian flu virus, strain H5N1. A possible hybrid between Little Egret Egretta garzetta and Western Reef Heron Egretta gularis was observed. The first nesting of Ruddy Shelduck Tadorna ferruginea in the Danube Delta was documented. Goldeneye Bucephala clangula and Smew Mergus albellus are re-colonising the areas they abandoned in the early 20th century. New data regarding the relocation of Pallas’s Gull Larus ichthyaetus colony in the Danube Delta as a result of hydromorphological changes in the bay, nesting and defence strategies against Caspian Gulls Larus cachinnans are described. Probable nesting of Citrine Wagtail Motacilla citreola in the Danube Delta was documented in 2014 for the f...
<p>The WNV sequence derived from a <i>Hyalomma marginatum marginatum</i> tick c... more <p>The WNV sequence derived from a <i>Hyalomma marginatum marginatum</i> tick collected from a song thrush in Romania (marked with a black diamond) is most closely related to the human-derived WNV strain VLG_07 from Russia. All other WNV strains related to this Russian/Romanian cluster originate from Central and South Africa, suggesting an introduction of this WNV lineage 2 variant from Africa to Europe. The cluster of another independent introduction of a WNV lineage 2 to Central Europe is also indicated. Black stars indicate sequences for which information was obtained from McMullen et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109905#pone.0109905-McMullen1" target="_blank">[12]</a>. The percentage of replicates in the bootstrap test (1000 replicates) is shown next to the branches. Values less than 70% are hidden.</p
Beaver (Castor fiber) in Danube Delta: present and future perspectives Before present no paleozoo... more Beaver (Castor fiber) in Danube Delta: present and future perspectives Before present no paleozoological, epigraphic or anecdotal evidence existed regarding the occurrence of beavers (Castor fiber) in the Danube Delta. Beavers were only established in bordering areas, and then only up to the early middle ages. The first data from modern times were collected on April 24, 2011, when locals from the Maliuc ranges acquired a specimen; a carcass was found by the authors on July 6. On February 12, 2012 the Danube Delta Biosphere Reserve Authority issued a statement regarding a beaver lodge located 15 km upstream of the trifurcation of the Danube. In this area the authors identified another lodge on June 5, 2013. These observations substantiate the migration of the beaver into the Danube Delta, possibly deriving from Bavarian specimens released into the river Ialomiţa in 2003. Permanent beaver settlement in the Danube Delta area is unlikely due to the difficulties encountered in the hydrog...
The authors study the feeding process of the White-tailed Eagles/ Haliaeetus albicilla (L.) / in ... more The authors study the feeding process of the White-tailed Eagles/ Haliaeetus albicilla (L.) / in the conditions present within the Danube Delta - Romania, reviewing a considerable amount of work on this. The diet of the White-tailed Eagles within the delta has been studied based on remnants of food harvested from and around their nests, during the growing period of the chicks, during 2010-2012. It was identified a wide range of food components, min. 40 taxa and at least 260 copies, which shows a remarkable daptability to the different conditions of food and the existence of different strategies for obtaining them. Due to the existence of an abundant trophic base in the Danube Delta, it is considered that not the food factor limits the size of the White-tailed Eagle populations from the territory, but especially the nesting opportunities and the human pressure, which is the main disturbing factor in obtaining food and breeding of this bird.
Scientific Annals of the Danube Delta Institute, 2019
In the period 2003-2006, a series of bird markings were performed in nesting colonies from the no... more In the period 2003-2006, a series of bird markings were performed in nesting colonies from the northern part of the Sinoie lagoon in the Danube Delta Biosphere Reserve. We marked with colour plastic and metal rings nestlings of breeding species as Dalmatian Pelican (Pelecanus crispus Bruch, 1832), Great Cormorant (Phalacrocorax carbo Linnaeus, 1758) and the Eurasian Spoonbill (Platalea leucorodia Linnaeus, 1758). We already published a series of preliminary results for Great Cormorant and the Eurasian Spoonbill (Kiss et al., 2007; Sándor et al., 2009), here we follow the publishing of recoveries received after 2009. This paper contains the results obtained after this date, integrating the information obtained from the other marked species, the Dalmatian Pelican, which was not previously discussed. At the same time, for a better interpretation of the results, a brief summary of the results from the previous phase is made.
BSTRACT. The European mink (Mustela lutreola L.) is critically endangered. The Danube Delta Biosp... more BSTRACT. The European mink (Mustela lutreola L.) is critically endangered. The Danube Delta Biosphere Reserve (DDBR) is one of the last refuges of this species. Within the DDBR the European mink is still widespread as indicated by 74 life captures in a number of expeditions between 2003 and 2011. No American mink (Neovison vison), a serious threat to the European mink, were trapped or observed during 2000 and 2011 in the DDBR. Trapping success varied both between years and between trapping areas, but up to know the underlying factors for these patterns are not understood. It may be a combination of generally changing mink densities in the Delta due to food availability or reproduction success and habitat quality as a local factor. In this context we discuss potential limiting factors and outline some aspects for a future management plan of the species.
In the context of climate change, globalization, and enhanced human traveling, arboviruses contin... more In the context of climate change, globalization, and enhanced human traveling, arboviruses continue to represent a threat to public health. West Nile and Usutu viruses are mosquito-borne viruses belonging to the Flaviviridae family (Flavivirus genus) and members of the Japanese encephalitis virus serocomplex. Included in the Togaviridae family (Alphavirus genus), the Sindbis virus is also vectored by mosquitoes. In the present study, we aimed to analyze the presence of antibodies concerning the abovementioned viruses in migratory and resident birds in the South-Eastern region of Romania, as avian hosts represent the main reservoir for human infection. Blood samples were collected from wild birds between May 2018 and October 2019 in nine locations from three counties. All the samples were serologically tested by ELISA and a serum neutralization test. Overall, a seroprevalence of 8.72% was registered for the West Nile virus, 2.71% for the Usutu virus, and 0% for the Sindbis virus. To ...
Additional file 2: Table S2. Records of the climatic parameters for each day of the sampling peri... more Additional file 2: Table S2. Records of the climatic parameters for each day of the sampling period included in the current study.
According to historical records, in the early twentieth century the Glossy Ibis was a common spec... more According to historical records, in the early twentieth century the Glossy Ibis was a common species in all the main wetlands of southern and eastern part of Romania. Due to habitat degradation and loss throughout the Danube floodplain and its main tributaries the breeding population underwent a dramatic decline, some colonies disappeared while others suffered considerable numerical decrease. At that time, the Danube Delta was considered to be the main refuge for the species in Romania which registered a maximum of 12,000 pairs in 1977 followed by a sharp decline to about 6,000 in 1979 and 525 in 1983. In the 1984-1995 period the population increased to 3,340 pairs and varied between 2000 – 3000 breeding pairs during the next decade. Although all known Glossy Ibis colonies from Romania are located in protected areas and have a good conservation status, recent annual surveys show large fluctuations in breeding population size. Whereas historical fluctuations have been mostly attribut...
Background In a countrywide study aiming to update the knowledge on diversity of sand fly species... more Background In a countrywide study aiming to update the knowledge on diversity of sand fly species in Romania, a sand fly population was observed in an isolated system of cave microhabitats. The caves are located in the protected area of Canaraua Fetii, Dobrogea region, southeastern Romania. The highest sand fly diversity was recorded in this area between 1968 and 1970. This work presents a study conducted to estimate the seasonal variation of the sand fly species in correlation with the particular environmental factors of the isolated system of cave microhabitats. Methods Sand flies were collected between May and October 2020 from one trapping site of interest in Canaraua Fetii. The trapping site consisted of a cave entrance. CDC miniature light traps and sticky traps were used to collect insects from the exterior walls of the cave entrance. Species identification of collected sand flies was done using morphological keys. Statistical analysis of the trapping and climatic data was pe...
Between 1931 and 2018 in the Danube Delta, 1,171 Great White Pelican (Pelecanus onocrotalus Linna... more Between 1931 and 2018 in the Danube Delta, 1,171 Great White Pelican (Pelecanus onocrotalus Linnaeus 1758) were ringed (731 with metal rings, 440 with coloured plastic rings) at breeding sites. The majority of the captured birds were flightless young individuals. From the ringed birds, 25 (2.13%) were reported as recaptured. Most were reported from Israel (28%), and the rest from 8 other countries. Recovery distance varied between 50 and 3,000 km. 19 birds (76%) were reported within half year after ringing, 2 birds (8%) within a year, and further 4 individuals (16%) were reported after a year. With the exception of a single photographed individual, all the others perished: they were shot or fell victims to accidents. These cases suggest high mortality in the young age cohort. Very little knowledge is available about the African wintering grounds; there are only two reports from Egypt and one from Southern Sudan. Traditional ringing yields little information for this species. Conside...
West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild b... more West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild birds as amplifying hosts and ornithophilic mosquito vectors. Bridge vectors can transmit WNV to mammal species potentially causing West Nile Fever. Wild bird migration is a mode of WNV introduction into new areas. The Danube Delta Biosphere Reserve (DDBR) is a major stopover of wild birds migrating between Europe and Africa. The aim of this study was to investigate the presence of WNV in the DDBR during the 2016 transmission season in wild birds and mosquitoes. Blood from 68 wild birds (nine different species) trapped at four different locations was analyzed by competitive ELISA and Virus Neutralization Test (VNT), revealing positive results in 8/68 (11.8%) of the wild birds by ELISA of which six samples (three from juvenile birds) were confirmed seropositive by VNT. Mosquitoes (n = 6523, 5 genera) were trapped with CDC Mini Light traps at two locations and in one location resting mosqui...
A number of faunistically interesting observations related to the avifauna of the Danube Delta (R... more A number of faunistically interesting observations related to the avifauna of the Danube Delta (Romania) are presented. In the spring of 2015, a mass mortality event with a minimum of 118 dead birds occurred in a major Dalmatian Pelican Pelecanus crispus colony in the Black Sea lagoons caused by the avian flu virus, strain H5N1. A possible hybrid between Little Egret Egretta garzetta and Western Reef Heron Egretta gularis was observed. The first nesting of Ruddy Shelduck Tadorna ferruginea in the Danube Delta was documented. Goldeneye Bucephala clangula and Smew Mergus albellus are re-colonising the areas they abandoned in the early 20th century. New data regarding the relocation of Pallas’s Gull Larus ichthyaetus colony in the Danube Delta as a result of hydromorphological changes in the bay, nesting and defence strategies against Caspian Gulls Larus cachinnans are described. Probable nesting of Citrine Wagtail Motacilla citreola in the Danube Delta was documented in 2014 for the f...
<p>The WNV sequence derived from a <i>Hyalomma marginatum marginatum</i> tick c... more <p>The WNV sequence derived from a <i>Hyalomma marginatum marginatum</i> tick collected from a song thrush in Romania (marked with a black diamond) is most closely related to the human-derived WNV strain VLG_07 from Russia. All other WNV strains related to this Russian/Romanian cluster originate from Central and South Africa, suggesting an introduction of this WNV lineage 2 variant from Africa to Europe. The cluster of another independent introduction of a WNV lineage 2 to Central Europe is also indicated. Black stars indicate sequences for which information was obtained from McMullen et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109905#pone.0109905-McMullen1" target="_blank">[12]</a>. The percentage of replicates in the bootstrap test (1000 replicates) is shown next to the branches. Values less than 70% are hidden.</p
Beaver (Castor fiber) in Danube Delta: present and future perspectives Before present no paleozoo... more Beaver (Castor fiber) in Danube Delta: present and future perspectives Before present no paleozoological, epigraphic or anecdotal evidence existed regarding the occurrence of beavers (Castor fiber) in the Danube Delta. Beavers were only established in bordering areas, and then only up to the early middle ages. The first data from modern times were collected on April 24, 2011, when locals from the Maliuc ranges acquired a specimen; a carcass was found by the authors on July 6. On February 12, 2012 the Danube Delta Biosphere Reserve Authority issued a statement regarding a beaver lodge located 15 km upstream of the trifurcation of the Danube. In this area the authors identified another lodge on June 5, 2013. These observations substantiate the migration of the beaver into the Danube Delta, possibly deriving from Bavarian specimens released into the river Ialomiţa in 2003. Permanent beaver settlement in the Danube Delta area is unlikely due to the difficulties encountered in the hydrog...
The authors study the feeding process of the White-tailed Eagles/ Haliaeetus albicilla (L.) / in ... more The authors study the feeding process of the White-tailed Eagles/ Haliaeetus albicilla (L.) / in the conditions present within the Danube Delta - Romania, reviewing a considerable amount of work on this. The diet of the White-tailed Eagles within the delta has been studied based on remnants of food harvested from and around their nests, during the growing period of the chicks, during 2010-2012. It was identified a wide range of food components, min. 40 taxa and at least 260 copies, which shows a remarkable daptability to the different conditions of food and the existence of different strategies for obtaining them. Due to the existence of an abundant trophic base in the Danube Delta, it is considered that not the food factor limits the size of the White-tailed Eagle populations from the territory, but especially the nesting opportunities and the human pressure, which is the main disturbing factor in obtaining food and breeding of this bird.
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