scholarly journals Cordulegaster bidentata Selys, 1843 in fragmented landscape of the Wielickie Foothills: reassesement of the northern limit of species range in the Western Carpathians

2021 ◽  
Vol 63 (2) ◽  
pp. 67-80
Author(s):  
Rafał BOBREK ◽  

In 2018–2019, the occurrence of Cordulegaster bidentata Selys, 1843 in the Wielickie Foothills, located between the Beskidy mountain ranges (in the south) and the Vistula river valley (in the north) was investigated. It was examined whether C. bidentata inhabits fragmented landscape, with forest patches of various sizes. Larvae of this dragonfly were searched in the forest streams, the bottom of which was visually scanned using binoculars. The presence of 49 larvae was confirmed on 17 stream sections out of 53 (32%). They were recorded in almost the entire geographical extent of the study area, from the southernmost to the northernmost forest patches. The neighboring occupied streams were separated by a maximum of 3.7 km, and breeding sites were found in forest patches of an area of 75–1280 ha. It was confirmed that C. bidentata occurs up to the orographic edge of the Western Carpathians. Its range is continuous between the northern edge of the Beskidy Mountains and the Vistula valley. New data shift the northern range limit of C. bidentata in the Western Carpathians by nearly 20 km. The field method used proved to be efficient in assessing the distribution of larvae in large areas, with relatively little field effort. Its wider use would allow a more complete recognition of distribution of C. bidentata in the Carpathian Foothills.

2006 ◽  
Vol 22 (5) ◽  
pp. 531-542 ◽  
Author(s):  
Deborah Faria

This paper addresses the effects of habitat fragmentation on the phyllostomid bats of the Atlantic rain forest in Brazil, by comparing community structure (species richness and capture frequency) and the frequency of three bat species sampled along 36 transects encompassing six habitat categories: interiors and edges of large (>1000 ha) and small fragments (<100 ha), and the surrounding matrix of second-growth forests and areas of shade cocoa plantation. Species composition, richness and total captures were not directly affected by forest size per se, although the frequency of one dominant forest species (Artibeus obscurus) was significantly lower in small fragments compared with larger ones. The high connectivity among forest patches in the study area and the ability of some species to use the surrounding matrix of secondary forests and shade cocoa plantations possibly precludes the insularization effect. Qualitative habitat changes induced by fragmentation, such as edge formation and forest regrowth affected bat community structure; both modified habitats comprised a limited subset of the species assemblage found in the interiors of mature forests. The results presented here provide evidence of impoverished bat assemblages in man-modified habitats linked with deforestation and overall disturbances related with forest fragmentation.


2011 ◽  
Vol 9 (2) ◽  
pp. 67-86 ◽  
Author(s):  
Dariusz Bukaciński ◽  
Monika Bukacińska ◽  
Arkadiusz Buczyński

The inventory of birds was conducted in the years 2005-2010 on the Vistula River section between Dęblin (388 km of the river) and Podwierzbie (435 km of the river). The study area includes a southern section of the European Ecological Natura 2000 Site in Poland PLB140004 „Middle Vistula River Valley” (IBA, PL083). In most areas the Vistula flows here within unregulated or relatively little modified riverbed, having features of natural, lowland, braided river. Sandy islands and braid bars within the main channel, steep banks, and old riparian afforestation create the unique breeding habitats of the Vistula River Valley. Especially the river channel habitats provide suitable breeding sites for many rare bird species, constituting some of them the key-breeding sites. There are, however, fragments of several kilometers, where people transformed the Vistula River in a more visible way (Table 1). These are, among others: an urban section within Dęblin boundaries (km 388-393 of the river), a fragment adjacent to Kozienice Power Plant (km 421-426), and the area, where since 2007 gravel for the industry has been mining from the river bottom (km 426-431). The aim of this inventory was the comparison of richness and abundance of breeding bird species associated directly with the river channel on fragments mentioned above. It will allow us to estimate soberly how very the intensity of human utilization of the river affects the distribution of avifauna of the Vistula, determining the richness and abundance of valuable and/or endangered species breeding in a given area.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Martin U. Grüebler ◽  
Johann von Hirschheydt ◽  
Fränzi Korner-Nievergelt

AbstractThe formation of an upper distributional range limit for species breeding along mountain slopes is often based on environmental gradients resulting in changing demographic rates towards high elevations. However, we still lack an empirical understanding of how the interplay of demographic parameters forms the upper range limit in highly mobile species. Here, we study apparent survival and within-study area dispersal over a 700 m elevational gradient in barn swallows (Hirundo rustica) by using 15 years of capture-mark-recapture data. Annual apparent survival of adult breeding birds decreased while breeding dispersal probability of adult females, but not males increased towards the upper range limit. Individuals at high elevations dispersed to farms situated at elevations lower than would be expected by random dispersal. These results suggest higher turn-over rates of breeding individuals at high elevations, an elevational increase in immigration and thus, within-population source-sink dynamics between low and high elevations. The formation of the upper range limit therefore is based on preference for low-elevation breeding sites and immigration to high elevations. Thus, shifts of the upper range limit are not only affected by changes in the quality of high-elevation habitats but also by factors affecting the number of immigrants produced at low elevations.


Author(s):  
Aivars Tērauds ◽  
Oļgerts Nikodemus ◽  
Inga Rasa ◽  
Simons Bells

Landscape Ecological Structure in the Eastern Part of the North Vidzeme Biosphere Reserve, Latvia Latvia is a country where the forest area has increased and habitat fragmentation has reversed compared with many other European countries. In order to examine the effect of this expansion on biodiversity, vegetation maps dating from 2002 and the years 1930-1936 were used for comparative landscape structure analyses while archive materials from forest plans, and data from the national forest management database were used for land use analysis. Four landscape ecoregions in the eastern side of the North Vidzeme Biosphere Reserve were selected for analysis. Landscape structure indicators derived from landscape ecology were used for the ecological assessment of land use changes. The total number of forest patches had decreased over the study period, but mean patch size had increased for all types of landscape element. This general change was found to vary between different landscape units in the study area. The biggest change in the area of forest patches occurred in the Rūjiena drumlin field, where the amount of forest patches decreased least and forest area increased the most. This study showed that the internal structure of the forest matrix changed substantially. This finding has implications for biodiversity protection if this trend of land use change continues.


Author(s):  
Piotr Włodarczak

The borderland of the Vistula Plain and the Proszowice Plateau is part of the loess zone extending mainly to the north of the Vistula River, known for numerous discoveries of archaeological sites from the Eneolithic period and the early Bronze Age. The state of reconnaissance of settlement is far from satisfactory here. From the final Eneolithic period primarily cemeteries of the Corded Ware culture (around 2800–2300 BC) are known. Falling within this age range is probably the only burial mound in the area, in Igołomia, which yielded a niche grave of the Corded Ware culture within the eastern part of its cover. Another cemetery was investigated in Rudno Górne, where niche graves of the culture in question were found dug into the embankments of Funnel Beaker culture megalithic graves from the middle Eneolithic period. From the early Bronze Age, the richest and most cognitively significant sites of the Mierzanowice culture (around 2200–1600 BC) are concentrated on loess hills rising above the valleys of Ropotek and Rudnik. They are both cemeteries and large settlements. Particularly valuable results were obtained during research on the cemetery in Szarbia, where as many as 44 graves were found. These findings enable the reconstruction of funeral rite rules from the early Bronze Age.


1965 ◽  
Vol 5 (40) ◽  
pp. 399-410 ◽  
Author(s):  
K. C. Arnold

Abstract Meighen Island lies in the centre of the north coast of the Queen Elizabeth Islands and fronts on the Arctic Ocean. An ice cap of about 76 km.2 covers about one-tenth of the island. Its greatest thickness of 150 m. occurs under the summit, near the south end, which was 268 m. above sea-level in 1960. The northern half of the ice cap is less than 30 m. thick; and the total volume is of the order of 2,000 × 106 m.3. Precipitation is low in the northern Queen Elizabeth Islands, and Meighen Island lies in an area where summer temperatures are lowest. In the winters of 1959–60, 1960–61 and 1961–62, the snow accumulation was 12.6, 18.2 and 14.1 cm. of water equivalent. Some snowfall remained on the higher part of the ice cap in the cold summer of 1961; but the ice cap diminished in volume in each year; by 36 × 106, 72 × 106, 22 × 106 and 91 × 106 m.3 in the 1959, 1960, 1961 and 1962 ablation seasons. If the conditions of these four seasons were maintained the ice cap would disappear in about 100 yr. However, a radio-carbon dating of a saxifrage exposed by the retreat of the ice from a small nunatak near the northern edge gave a date of less than 100 yr., and it appears that the existence of the ice cap might be sensitively related to recent climatic change. Careful surveys were made in 1959, 1960 and 1961 in an attempt to detect movement in the ice cap. Unequivocal evidence is not available from these surveys; but the stake network has been maintained and another survey has recently been completed.


2020 ◽  
Vol 66 (6) ◽  
Author(s):  
Sarah A. Mueller ◽  
Tobias E. Reiners ◽  
Katharina Steyer ◽  
Alina von Thaden ◽  
Annika Tiesmeyer ◽  
...  

AbstractFollowing severe population decline and local extinction due to massive habitat destruction and persecution, wildcats have recently reappeared in several parts of Germany’s low mountain region. It remains unknown how this reemergence occurred, specifically if local populations have been overlooked at low densities or if the species has successfully spread across the highly fragmented anthropogenic landscape. In the central German Rhön Mountains, for instance, wildcats were believed to be extinct during most of the twentieth century, however, the species was recently detected and subsequent genetic monitoring found the presence of a sizeable population. In this study, we used microsatellite and SNP genotypes from 146 wildcat individuals from 2008 to 2017 across a ~ 15,000 km2 area in the central German low mountain region to understand the population re-establishment of wildcats in the region. Bayesian clustering and subsequent analyses revealed that animals in the Rhön Mountains appear to be a mix from the two adjacent populations in the North and South of the area, suggesting a recent range expansion from two different directions. Both populations meet in the Rhön Biosphere Reserve, leading to an admixture of the northern, autochthonous, and the southern reintroduced wildcat population. While we cannot completely exclude the possibility of undetected population persistence, the high genetic homogeneity in the central German wildcat population and the lack of any signatures of past population decline in the Rhön favor a scenario of natural expansion. Our findings thus suggest that wildcats are well capable of rapid range expansion across richly structured landscape mosaics consisting of open land, settlements, and forest patches and document the potential of massive non-invasive genetic sampling when aiming to reconstruct the complex population and range dynamics of wildlife.


Author(s):  
Sheila S. Anderson

SynopsisThe distribution and status of grey and common seals around Shetland is reviewed. Recent surveys have produced an accurate picture of the location of breeding sites, grey seals being found at discrete localities mainly in the north and west of the islands and common seals being distributed more widely throughout the archipelago. The population of grey seals is estimated at 3,500 animals and is considered to be relatively constant. The reliability of boat surveys for estimating common seal populations is discussed. It is concluded that the population of Shetland has increased in numbers following protective legislation and it is suggested that there has also been a change in hauling out behaviour. The current population consists of at least 4000 individuals.Grey seals do not appear to have been affected by oil developments at Sullom Voe so far, but common seal numbers in the Sullom Voe area have not increased at the same rate as elsewhere in Shetland, and the number of pups present has declined. It is suggested that these changes may have arisen as a result of the development of the oil terminal. Study methods which would enable the nature and causes of these changes to be identified are proposed.


2016 ◽  
Vol 11 (3) ◽  
Author(s):  
Verônica Santos Barbosa ◽  
Ricardo José de Paula Souza E Guimarães ◽  
Rodrigo Moraes Loyo ◽  
Constança Simões Barbosa

The occurrence of schistosomiasis is directly linked to the presence of its snail intermediate host <em>Biomphalaria</em> spp. Knowledge of geographical distribution, habitats and behaviour of these snails in relation to the climate is essential for guiding measures for disease prevention and control. This study aims to model the distribution of <em>B. glabrata</em> and <em>B. straminea</em> in schistosomiasis non-endemic areas of the metropolitan region of Recife (MRR) based on environmental data and estimates of snail distributions in endemic and neighbouring areas. We applied Kriging with the aim of determining the spatial distribution of these two snail species and MaxEnt for modelling their ecological behaviour. Kriging showed that the North and the Centre of the MRR were generally either snail-free or contained only <em>B. straminea</em>, while both snail species could be found in the South. MaxEnt supported our observation that the northern and southern coastal regions were favoured by <em>B. glabrata</em> and diurnal mean temperature variation; July rainfall and November rainfall were the three variables favouring <em>Biomphalaria</em> breeding sites that contributed the most in the predictive model we developed. The study showed the location of areas suitable to <em>Biomphalaria</em> spp. and therefore at potential risk, first for invasion of these snails and later for the development of new schistosomiasis- endemic areas. This information should be useful, not only to estimate expansion possibilities of this disease in the MRR, but also to point out the climatic variables that would contribute to this expansion, thereby allowing timely application of prevention and control measures.


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