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Comparative Data on the Trophic Spectrum of Syntopic Bombina variegata and Rana temporaria (Amphibia: Anura) Populations from the Iezer Mountains, Romania
Sára Feren?i,Severus-D. Covaciu-Marcov
Ecologia Balkanica , 2011,
Abstract: In August 2009, we compared the trophic spectrum of syntopic Bombina variegata and Rana temporaria populations from the Bratia Valley in the Iezer Mountains. The separation of the trophic niche observed between the juveniles and the adults of R. temporaria is caused by the differences in size between them, differences that influence their jump. The main consumed prey taxa by Rana temporaria is represented by Arahnida, Gastropoda and Hymenoptera. Furthermore, the differences between the sizes of their mouths separate the trophic niche between the two species. Our results indicate a trophic selectiveness for B. variegata, which prefers ants. Despite the fact that the two species share the same habitat, the ants were consumed mostly by B. variegata. This is probably a consequence of the fact that B. variegata is a poisonous species, the toxins being able to originate from their preys – as are ants as well. The lack of competition for the two species indicates a rich trophic offer, enough to satisfy the energy needs of both species in contact in a limited space.
Data on Population Dynamics of Three Syntopic Newt Species from Western Romania
Alfred-S. Cicort-Lucaciu,Nicoleta-R. Radu,Cristiana Paina,Severus-D. Covaciu-Marcov
Ecologia Balkanica , 2011,
Abstract: We studied the population dynamics of three syntopic newt species [Mesotriton alpestris (Laurenti, 1768), Lissotriton vulgaris (Linnaeus, 1758) and Triturus cristatus (Laurenti, 1768)] in Zarand Mountains (Arad County, Romania). M. alpestris had the shortest aquatic phase, approximately two months, out of which the nuptial display was 2-3 weeks long. L. vulgaris and T. cristatus spent three months in the habitat, having a nuptial display of 2-3 weeks for L. vulgaris, and of 4-5 weeks for T. cristatus. M. alpestris had the highest degree of reproductive synchronization, while this was the lowest at T. cristatus. Males from all three species had a higher affinity for the aquatic habitat than females. The population size was estimated at 769 for L. vulgaris, 588 for T. cristatus, and 294 for M. alpestris. Balanced sex ratio was observed in the peak of breeding activity for all species.
Implication upon Herpetofauna of a Road and its Reconstruction in Carei Plain Natural Protected Area (Romania)
Alfred-S. Cicort-Lucaciu,Severus-D. Covaciu-Marcov,Horia V. Bogdan,Istvan Sas
Ecologia Balkanica , 2012,
Abstract: In autumn 2011 we monitored a 5 km long road, paved with cobblestone, situated in Carei Plain Natural Protected Area, a road that is due to be modernized and continued across the border into Hungary. Dead bodies from eight different animal groups were observed on the road, amphibians presenting the greatest amount. The most frequent were the Triturus dobrogicus corps, a species with conservation importance. The amphibians were affected in the areas where the road is neighboring the wetlands, while on the opposite pole sits the area with acacia plantations. The high number of mortalities recorded on the road, despite the low traffic speed, is alarming. It is likely that the modernization of the road that will surely increase its traffic and the speed of the vehicles, will make the situation even worse. However, the rebuilding could contribute to the reduction in the impact on amphibians, if certain measures are considered while planning the action. Thus, in the areas near the wetlands, there should be undercrossings, fences and speed limits. In this way, the modernization would at least represent an experiment regarding the diminution of the road’s impact on amphibians.
On the presence of Rana (Pelophylax) lessonae in south-western Romania: distribution, biogeographical signification and status
Severus D. COVACIU-MARCOV,István SAS,Diana CUPSA
North-Western Journal of Zoology , 2008,
Abstract: During 2006 and 2007 we encountered in south-western Romania four populations of Rana lessonae. Their determination was made on the basis of both the morphological and chromatic features. All of the pool frog records in Romania are found at the proximity of the species’ general range; being practically in connection with it. Thus, aside from the glacial refuge from Italy, the populations from south-western Romania are amongst the most southerly populations of the species at entire Europe level, making up the south-eastern limit of its range. The populations from south-western Romania seem to be isolated from the other populations from Romania both geographically, ecologically (temperature and humidity), and as habitat type (mountain brook). It can therefore be theorized that the species Rana lessonae had in south-western Romania a secondary glacial refuge.
Lissotriton vulgaris paedomorphs in south-western Romania: a consequence of a human modified habitat?
Severus D. Covaciu-Marcov,Istvan Sas,Alfred ?. Cicort-Lucaciu,Horia V. Bogdan
Acta Herpetologica , 2011,
Abstract: A Lissotriton vulgaris paedomorph population was identified for the first time ever in south-western Romania. The newts inhabiting a permanent but artificial habitat, surrounded by agricultural fields.
Are the hibernating water frogs from Pelophylax (Rana) esculentus complex (from North-Western Romania) able to adapt to the thermal water conditions?
István Sas,éva-Hajnalka Kovács,Severus D. Covaciu-Marcov
Advances in Environmental Sciences , 2009,
Abstract: We were interested to determine if the hibernanting Pelophylax ridibundus and the othertwo forms of water frogs from the Pelophylax esculentus complex (Pelophylax lessonae, Pelophylaxesculentus) fulfil the requirements of thermal resistance in order to become adapted to the thermalhabitats. During the experiment we had determined for each frog the value of two parameters: VTMaxand CTMax. The experimental determination of the resistance to temperature of the water frogs fromthe P. esculentus complex has revealed a great resistance of these frogs to high temperatures.Although the difference among the analysed frogs is not significant concerning the values of thevoluntary and critical thermal maximum, it still can be observed a specific hierarchical order. Thisresistance (an average of 34.52oC), observed in the case of the hibernating populations of P.ridibudnus indicates the reason why the marsh frogs can adapt so easily to the conditions fromthermal waters. The voluntary thermal maximum obtained for the hybrid Pelophylax kl. esculentusdoes not differ noticeably, having an average value of 33.31oC. The lowest values for this parameterwere recorded for the Pelophylax lessonae species (an average of 33.02oC).
Eryx jaculus (Reptilia, Boidae) north of Danube: a road-killed specimen from Romania
Severus D. Covaciu-Marcov,Sára Feren?i,Alfred S. Cicort-Lucaciu,István Sas
Acta Herpetologica , 2012,
Abstract: In September 2011 we identified a killed specimen of Eryx jaculus on the road between the towns of Turnu M gurele and Corabia, in southern Romania. This seems to be the first record of the species north of the Danube. Although surprising, the identification of E. jaculus in the area is interpreted in the light of the presence of other species of herpetofauna in the Danube floodplain with similar ecological requirements, reaching here their northern distribution limit. Survival of the species appears to be favoured by the existence of some protected areas in the region.
Comparison of Terrestrial Isopod (Isopoda, Oniscidea) Assemblages from Two Types of Forests from North Western Romania
Sára Feren?i,Severus-Daniel Covaciu-Marcov
Ecologia Balkanica , 2012,
Abstract: In 2008 we compared the terrestrial isopod assemblages from two different habitats, a beech forest and a mixed beech and spruce forest, from north western Romania (Huta Certeze locality). The samples were taken from April to September using pitfall traps. We identified a total of 7 species: Ligidium germanicum, Trichoniscus sp., Hyloniscus transsilvanicus, Protracheoniscus politus, Porcellium collicola, Trachelipus difficilis and Porcellio scaber. A greater diversity and species richness were noticed in the beech forest. The poverty of species in the mixed forest was a consequence of the forest type, the anthropogenic impact and the dry environment. High surface activity of individuals was noticed in the summer months. Even if the species compositions of the two compared isopod assemblages were not identical, there weren’t statistically significant differences between them.
Studies on the dynamics of the macrozoobenthic invertebrate groups in the thermal lake Ochiul Mare natural reserve (Bihor county, Romania)
Diana CUPSA,Istvan SAS,Ilie TELCEAN,Severus-Daniel COVACIU-MARCOV
Analele Universitatii din Oradea, Fascicula Biologie , 2005,
Abstract: In the thermal lake from Ochiul Mare the environmental conditions and especially the temperature of the water which do not drop under 200C in the substrate even in winter period determine a different dynamics of the macrozoobenthic populations than in other natural waters. Also the major groups in the communities differ from those of the non thermal waters. For these reasons we have studied the dynamics of the macroinvertebrate groups from the benthos to find out if they adapted their life cycles to the thermal environment. Also we wanted to find out which are the groups which have the greatest densities in the thermal environment and for which this environment is a limitating factor of the development.
The populations of Rana arvalis Nills. 1842 from the Ier Valley (The Western Plain, Romania): present and future
I. Sas,S.D. Covaciu-Marcov,E.H. Kovacs,N.R. Radu
North-Western Journal of Zoology , 2006,
Abstract: The objectives of the current study were to identify, in detail, the distribution of the largest moor frog populations from the Ier Valley region and to assess the zones that represent important habitats and present measures for their protection. Our study was conducted from March to October during the years 2001-2003. We identified 49 populations of Rana arvalis in The Ier Valley area. Most of these populations can be considered distinct, isolated from each other, apart from a few exceptions. This fact increases their regional chance of extinction. The Rana arvalis populations in the studied area occupy very different habitats. Only a few of these habitats can be considered natural biotopes. As a result of intense dry out of the swamps in the Ier Valley area, the populations of Rana arvalis had reduced in atypical smaller sized habitats, which had a limitating effect on the size of these populations. Small numbers of moor frogs were found in most sites surveyed (less then 6 specimens / site / visit) in the region. We were able to calculate quantitative population assessments for five populations. The largest population was found near Andrid, with 675 ±57 adult specimens, making this one of the largest known population of Rana arvalis in Romania. The second significant population was estimated to be 354 ±25 individuals and it was located near Resighea. The other populations’ sizes were estimated at fewer than 200 adults. We consider the protection of the large breeding populations of Rana arvalis in the Ier Valley area to be a priority, by managing both the breeding and foraging habitats. The potential for the biggest moor frog populations to be part of a single infrastructure is discussed.
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