Species Composition and Distribution of Invasive Ponto‐Caspian Amphipods in the Off‐Channel Microhabitats of a Temperate,Lowland Dam Reservoir

The Włocławek Dam Reservoir located on the lower Vistula River (central Poland) is part of the central corridor used by Ponto‐Caspian species to migrate in Europe. It provides a number of habitats suitable for sustaining populations of several non‐indigenous taxa. Four Ponto‐Caspian amphipod species were recorded in the reservoir: Chaetogammarus ischnus, Chelicorophium curvispinum, Dikerogammarus haemobaphes and Pontogammarus robustoides. We found significant differences in amphipod densities and species composition among various microhabitats in off‐channel areas. P. robustoides was the only amphipod species that occurred on very shallow (<1 m) sandy bottom near the shore. It inhabited also other sites but its share in the total number of amphipods and abundance decreased with the distance from the shore. Furthermore, at sites more distant from shore its affinity for plant substratum was higher. D. haemobaphes, C. ischnus and C. curvispinum clearly preferred sites distant from shore, overgrown by macrophytes or covered by mussel shells. Furthermore, the abundance of C. ischnus was negatively correlated with the presence of P. robustoides. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Parasitic microfungi of the Tatra Mountains: 5. <Emphasis Type="Italic">Plasmopara</Emphasis> representatives on the species of <Emphasis Type="Italic">Geranium</Emphasis>

A list of species and the distribution of the members of Plasmopara (Chromista, Peronosporales) on Geranium spp. in the Tatra National Park (Western Carpathians) biospheric reserve are given. Three fungal species parasitizing 3 plant species were recorded in the area. Plasmopara praetermissa is a species new to Poland and Slovakia.     

Mite communities (Acari,Mesostigmata) associated with <Emphasis Type="Italic">Ips typographus</Emphasis> (Coleoptera,Scolytidae) in managed and natural Norway spruce stands in Central Europe

Previous studies have suggested that forest management practices can influence bark beetle populations as well as those of some associated insects. However, the impact on bark beetle-associated mites, which occur in bark beetle galleries in large numbers, have not yet been studied. The objective of this study was to compare mesostigmatid mite communities associated with the Norway spruce pest Ips typographus in managed and natural forest stands separated by spruce-free belt. The study sites were located in Białowieża National Park (NE Poland) as well as in the Izery Mountains (Szklarska Poręba Forest District — SW Poland), which were destroyed in 1981–1987 by an ecological disaster. In total, 30 Borregard pipe traps containing the commercial attractant Ipsodor W (Chemipan, Poland) were set up at each study site and collected in August 2010. In total, 7214 bark beetles and 1804 mites were collected which were classified into 16 species. We observed differences in the total abundance of mites as well as the total number of recorded mite species. The communities were quite similar, and were generally dominated by populations of Trichouropoda polytricha, Dendrolaelaps quadrisetus and Uroobovella ipidis. The Shannon and Evenness indexes as well as the mean number of mites per sample were not significantly different between forests.     

The occurrence of Ambrosia pollen in Rzeszów,Kraków and Poznań, Poland: investigation of trends and possible transport of Ambrosia pollen from Ukraine

Previous studies have shown that ragweed pollen arrives in Poland from sources in the south, in Slovakia, the Czech Republic, Hungary and Austria. It is likely that ragweed pollen also arrives from sources in the southeast (e.g. Ukraine). This hypothesis was investigated using 13 years of pollen data and back-trajectory analysis. Ambrosia pollen data were collected at three sites in Poland, Rzeszów, Kraków and Poznań. The amount of ragweed pollen recorded at Rzeszów was significantly higher than in Poznań and Kraków. This can be related to either a higher abundance of local populations of Ambrosia in south-east Poland or the proximity of Rzeszów to foreign sources of ragweed pollen. The combined results of pollen measurements and air mass trajectory calculations identified plumes of Ambrosia pollen that were recorded at Rzeszów, Kraków and Poznań on 4 and 5 September 1999 and 3 September 2002. These plumes arrived at the pollen-monitoring sites from an easterly direction, indicating sources of Ambrosia pollen in eastern Poland or Ukraine. This identifies Ukraine as a possible new source of ragweed pollen for Poland and therefore an important source area of Ambrosia pollen on the European Continent.     

Chrysomelid communities (Chrysomelidae, Coleoptera) of xerothermic grasslands (Inuletum ensifoliae) in the Wyżyna Miechowska Uplands (Central Poland)

The species composition, abundance and dominance structure of chrysomelids were characterized in xerothermic grasslands in southern Poland (Wyżyna Miechowska Uplands). During a two-year study, a total of 54 species was recorded; the mean value of the abundance index was 9.3, Longitarsus obliteratus and Derocrepis rufipes being eudominants. The species composition and quantitative structure of the community were similar (S = 80.0%, Re = 70.5%) but diversity, evenness and dominance indices of the community changed slightly although the abundance dynamics of the beetles varied significantly in the study years.     

Multiple host-ant use by the predatory social parasite <Emphasis Type="Italic">Phengaris</Emphasis> (=<Emphasis Type="Italic">Maculinea</Emphasis>) <Emphasis Type="Italic">arion</Emphasis> (Lepidoptera,Lycaenidae)

Phengaris (=Maculinea) arion is an endangered social parasite of Myrmica ants, and for a very long time was considered as specific to Myrmica sabuleti. Previous studies carried out in Poland suggested some discrepancies within this assumption, and therefore a much more intensive survey was undertaken. The host ant use of P. arion was studied at five sites in different types of biotopes in Poland, i.e. xerothermal grasslands where Thymus pulegioides was used as a larval food plant by the butterfly, and more or less sandy biotopes with Thymus serpyllum. Altogether nine Myrmica species were recorded, and considerable variation in species composition and density of nests was recorded. At four localities M. sabuleti proved to be the most common ant. A total of 529 Myrmica nests were examined, and only 20 of them contained larvae and pupae of P. arion. Host ants belonged to five different species, i.e. M. sabuleti, Myrmica scabrinodis, Myrmica schencki, Myrmica lobicornis and Myrmica hellenica. Only at one site (NE Poland) was a significant heterogeneity in parasitation rates among Myrmica species detected. M. lobicornis was the most often infested ant there, which may suggest local specialisation of the butterfly. Overall low parasitism rates may explain the vulnerability of P. arion in Central Europe but further studies are also necessary.     

Mite species inhabiting commercial bumblebee (<Emphasis Type="Italic">Bombus terrestris</Emphasis>) nests in Polish greenhouses

Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.     

Demographic variation of dwarf birch (<Emphasis Type="Italic">Betula nana</Emphasis>) in communities dominated by <Emphasis Type="Italic">Ledum palustre</Emphasis> and <Emphasis Type="Italic">Vaccinium uliginosum</Emphasis>

The structure and demographic processes were compared in shrub communities to test the effects of vegetation succession on population growth, fecundity and abundance of the dwarf birch (Betula nana L.), which is a rare and endangered plant species in Poland and a glacial relict in Central Europe. The effects of Ledum palustre L. and Vaccinium uliginosum L. were studied in the Linje nature reserve in Chełmińskie Lake District (northern Poland), in three permanent plots on a peat bog. Vegetative growth and reproduction of B. nana were lower in plant communities dominated by L. palustre and V. uliginosum, than in a reference site. Fecundity was also lower, despite the fact that the percentage share of potentially fertile age groups was similar in all study sites. Mortality of ramets was independent of vegetation, both for juvenile and mature stages. The results confirm that B. nana is intolerant of shade, and it is more abundant in vegetation without competitors. Light limitation can lead to its decline, primarily by a decrease in vegetative growth. Sexual reproduction may be negatively affected by shade, but it plays only small role in population growth. Butterfly larvae can destroy inflorescences, and thus contribute to low effectiveness of sexual reproduction. Increasing density of shrubs and trees in peat bogs can reduce the abundance of dwarf birch, and can lead to the extinction of its local populations.     

Factors affecting spatial and temporal distribution of Ostracoda assemblages in different macrophyte habitats of a shallow lake (Lake Fehér,Hungary)

Spatial and temporal distribution, abundance and habitat preferences of ostracod assemblages were studied in various habitats of Lake Fehér in Hungary. Of the 20 species Fabaeformiscandona hyalina and Cypridopsis hartwigi are new to Hungary. Significant spatial differences were recorded in the composition and abundance of the Ostracoda assemblages in the different habitats. The most diverse and abundant assemblages were found in the reed-belt, however, the mean abundance of the species differed in the different macrophyte communities of the reed-belt. The species richness and abundance were considerably lower in disturbed sites than in the other habitats. Most of the 20 species showed distinct habitat preferences and ecological tolerances. Especially the presence and coverage of the vegetation and the dissolved oxygen content influenced the distribution and abundance of the species.     

A mowing experiment to evaluate the influence of management on the activity of host ants of <Emphasis Type="Italic">Maculinea</Emphasis> butterflies

Maculinea butterflies obligatory parasitize certain species of Myrmica ants. Thus, the presence of the host ant species is a limiting factor for the survival of a Maculinea population. Here, we analyse the influence of vegetation structure and ground temperature on ant diversity and abundance on Maculinea habitats, with the final aim of identifying the environmental variables determining patterns of variation in species composition in order to recommend a mowing regime that will promote our three target species: Maculinea teleius, M. nausithous and M. alcon. Experimental plots with different mowing regimes were established at eight sites in South-Eastern Germany, a region which still contains a number of relatively large, stable populations of these threatened butterfly species. Among the seven different ant species recorded, four belong to the genus Myrmica (M. scabrinodis, M. rubra, M. ruginodis and M. vandeli). Among these, M. scabrinodis results most abundant at all sites. In a CCA analysis of environmental variables recorded at the studied plots, ant species diversity appears largely determined by litter cover, mean temperature, and mean grass cover. Mowing once a year, in the second half of September, after the larvae have left their host plants, enhances the abundance of Myrmica ants in the meadows, and would be the best management compromise for all three species.     

Habitat and conservation of the enigmatic damselfly <Emphasis Type="Italic">Ischnura pumilio</Emphasis>

Ischnura pumilio is threatened in the UK and its habitat requirements are not well understood. This study tests previously held notions of the habitat requirements of I. pumilio, investigates the features of a habitat influencing odonate species composition and provides recommendations for habitat creation and management for I. pumilio persistence. Thirty-one sites across south west England with past I. pumilio records were surveyed in 2006. Environmental variables and odonate abundance were recorded. Odonate species composition and I. pumilio abundance were related to environmental variables using multivariate techniques and GLM. Ischnura pumilio was found at a wide variety of habitat types; key habitat features were a muddy substrate with some open ground, turbid water, and low levels of shade. It was associated with increased structural diversity of vegetation away from water but low maximum height; characteristic of early-successional sites. The variables predicting odonate composition were location, shade, level of disturbance, water depth, and cover of terrestrial dwarf shrubs and Sphagnum species. Vegetation height and structure were also highly influential to at least 20 m from water. This study indicates that odonate habitat management should include adjacent hinterland. Management for I. pumilio may be complicated by the species’ use of two habitat types, each with associated problems. Furthermore, odonate species diversity was negatively associated with I. pumilio abundance, which may cause conflict of interest when managing habitats.     

Rocky shore turfs dominated by Corallina (Corallinales,Rhodophyta) in northern Japan†

Three intertidal sites dominated by Corallina turfs were investigated in Hokkaido, Japan. The sites (A, B and C) differed in slope, wave exposure and length of time exposed to air during tidal cycles. Monthly samples were analyzed for frond morphology and other features. Site A, the most wave-exposed site, was dominated by Corallina sp. X, an unknown species, and sites B and C by Corallina pilulifera Postels et Ruprecht. At the different sites the populations differed in conceptacle abundance, coverage by epiphytic Titanoderma corallinae (P. Crouan et H. Crouan) Woelkerling, Chamberlain et Silva, amount of contained sediment, numbers of axes per quadrat, numbers of branch fusions, branch entanglement, frond dryweight, frond length, amount of adventitious branching, numbers of epiphytes (exclusive of T. corallinae), and numbers of animal species. Ninety-one animal species were recorded from the turfs. Corallina is affected morphologically by conditions inherent in its microhabitat, including desiccation, epiphyte loading and the abundance of herbivores.     

Reintroduction of beavers <Emphasis Type="Italic">Castor fiber</Emphasis> may improve habitat quality for vespertilionid bats foraging in small river valleys

Beavers strongly modify their environment by not only building dams and creating ponds, which slow the water flow, but also by selective cutting and removing of trees, which change the spatial structure of the forest. We aimed to test the hypothesis that beaver activity promotes new foraging sites for insectivorous bats. The beaver’s influence can be especially significant on aerial hawkers that prefer moderate structural clutter, like the Pipistrellus species (by creating new canopy gaps), and on water-surface foragers, like Myotis daubentonii (by creating ponds with smooth water surface). The study was conducted on small streams in forest areas of northern Poland, which were colonized by the European beaver (Castor fiber). Bat activity was recorded with a Pettersson D-980 ultrasound detector on line transects. The number of bat passes was significantly higher in the stream sections modified by beavers (flooded and subjected to intensive tree cutting) than in the unmodified sections (for Pipistrellus nathusii, Pipistrellus pipistrellus, Pipistrellus pygmaeus, Nyctalus noctula, and all species lumped together). Contrary to our expectations, the activity of the Myotis species was significantly lower on the transect with the largest beaver ponds, possibly due to the blanket of duckweed (Lemnaceae), which is known to produce clutter echoes, thereby reducing prey detection by echolocating M. daubentonii.     

Comparison of frog assemblages between urban and non‐urban habitats in the upper Blue Mountains of Australia

1. World wide, and in Australia, many frog populations have declined over the last two decades. The present study was undertaken to determine whether urbanization has affected frog diversity and abundance. 2. Five urban sites were paired with non‐urban sites. Urban sites were in Katoomba and Blackheath, and were subject to physical environmental disturbance and impacted by storm water pollution due to urban runoff. Non‐urban sites were in the Blue Mountains National Park and were effectively subject to no human impact. 3. Water quality at urban sites was typical of sites polluted with sewage, while non‐urban sites exhibited water quality typical of ‘pristine’ natural bushland streams. 4. Six species were found at urban sites (Litoria peronii, Litoria dentata, Litoria verreauxii, Limnodynastes dumerilii, Limnodynastes peronii, Crinia signifera), with up to four species present at a site. Only one species (C. signifera) was recorded at non‐urban sites, and frogs were absent from most non‐urban sites. 5. The situation in non‐urban sites mirrors the trend of decline observed in other montane regions. Surprisingly, frog abundance and diversity were higher in urban habitats, running counter to this trend. 6. We hypothesize that the salts, detergents and other chemicals in urban wastewaters provide frogs with a level of protection against disease, particularly chytridiomycosis.     

Shoreline distribution and parasite infection of black‐striped pipefish Syngnathus abaster Risso, 1827 in the lower River Danube

This study aimed to characterise the shoreline distribution and metazoan parasite community in black‐striped pipefish Syngnathus abaster along the freshwater section of the River Danube (Bulgaria). An extensive survey of the shoreline zone showed the regular presence of S. abaster along the entire stretch from Vetren to Vrav (395–836 river km). The preference of shoreline habitat was analysed using abundance data and the proportion of this species in the fish community within particular habitat types. Highest frequencies of occurrence and density were found in sites with a muddy substrate, as compared to gravel and sand. A subsample of S. abaster from the upper section of the Bulgarian stretch was examined for metazoan parasites. The parasite fauna comprised eight metazoan species, representing half the parasite species richness known from its original range. Only three parasite species previously reported from S. abaster were found in the Danubian range of expansion: the adult trematode Orientocreadium siluri, metacercariae of Diplostomum sp., and an accidental finding of the trematode Nicolla skrjabini. The other five species appear to have been acquired in the new area, although these were recorded at a very low prevalence and/or abundance. Syngnathus abaster, therefore, is not likely to represent an important component in native parasite life cycles. Fish condition was not affected by either total parasite abundance or abundance of core species. Regular occurrence and dominance of Syngnathus abaster indicates that this species now represents a significant component of the Danubian shoreline fish community.     

Discovery of <Emphasis Type="Italic">Dermacentor reticulatus</Emphasis> (Acari: Amblyommidae) populations in the Lubuskie Province (Western Poland)

The distribution of the meadow tick, Dermacentor reticulatus (Fabricius) is divided into two separate areas—Western Europe and Eastern (Russian). The break in distribution of this species falls in Poland, as well as other sites. The populations of D. reticulatus in Poland, which have been confirmed by collecting ticks from vegetation, are located in the north-eastern and western parts of the country, although there are also reports of D. reticulatus occurring on hosts in several parts of Poland which have not been confirmed by collecting ticks from vegetation. Until this research was carried out, the view was that this species does not occur in the western part of Poland in the area between the Vistula and Oder rivers. In the site surveys conducted in the Lubuskie Province (western part of Poland around the city of Zielona Góra, about 55 km from the Polish-German border), during the springtime activity peak for adult stages looking for hosts, seven natural implantations of D. reticulatus were discovered where 208 tick specimens were collected by flagging. These were exclusively adult stages, including 127 females and 81 males. Because of the distance (around 350 km) from the nearest focus in Mazuria in North-eastern Poland, the populations discovered have been named the D. reticulatus “Lubuskie Focus”. The research proves for the first time that D. reticulatus occurs in Western Poland. The research indicates that D. reticulatus is the second most important tick in Poland, after Ixodes ricinus (L.), which is epidemiologically very important, especially as a parasite on dogs and cattle. The proliferation of the meadow tick in Central Europe is inseparably linked with the expansion of canine babesiosis.     

Response of ground-dwelling beetle (Coleoptera) assemblages to giant knotweed (<Emphasis Type="Italic">Reynoutria</Emphasis> spp.) invasion

Giant knotweeds (Reynoutria spp.) are highly productive and aggressive invaders in riparian wetlands of Europe and North America. We sampled ground-dwelling beetles by pitfall traps from six sites comparing monotypic Reynoutria stands with the invaded native Urtica-dominated stands. Three sites were located in a semi-natural softwood forest and three sites were on a ruderal embankment. The analyses are based on a total of 13,244 individuals from 218 species. Location and site significantly influenced beetle assemblages. Moreover, there were pronounced differences between vegetation stands. The monotypic Reynoutria stands exhibited lower beetle abundance, species richness and rarefaction diversity irrespective of location. However, the negative effect on species richness, abundance and assemblage similarities were stronger on the transformed ruderal embankment than in the semi-natural softwood forest. Reynoutria invasion seems to influence microclimatic conditions. We found a higher abundance of silvicolous and a lower abundance of xerophilous ground beetles in the Reyountria stands than in the Urtica-dominated stands. Feeding guilds reacted differently to Reynoutria invasion that reduced the abundance of predators and herbivores but enhanced that of detritivores. Detritivores assumingly profit from the perennial presence of the large quantities of Reynoutria litter. We conclude that highly productive invaders pauperise the arthropod fauna and alter link strengths in trophic cascades shifting primary producer-based food webs to detritus-based food webs.     

Expansion of the Mediterranean Gull Larus melanocephalus in Poland

Since 1981, when the first breeding pair of Mediterranean Gull Larus melanocephalus was recorded in Poland, the population of this gull has increased considerably. Its population size was stable until 1997, not exceeding ten pairs annually; thereafter, an increasing number of sightings were made, and during the last 5 years between 26 and 39 breeding pairs have been recorded in Poland. To date, breeding sites have been established in a total of 45 sites (maximum of 19 sites in a given year), with 27% of these (43% of all broods) found on islands located in the middle course of the Vistula River. Breeding sites have also included artificial reservoirs, such as dam reservoirs (20% of sites, 19% of broods), gravel pits (9% of sites, 13% of broods) and fishponds (24% of places, 8% of broods). Mediterranean Gulls were found to nest only within the colonies of other Laridae. Single pairs were recorded at 40% of the breeding sites, whereas a maximum of two to five pairs were recorded at 47% of the other sites. The great majority of breeding attempts were recorded in Black-headed Gull L. ridibundus colonies. In two cases, Mediterranean Gulls bred within mono-specific colonies of Common Gulls L. canus consisting of 60–150 pairs. The biggest concentrations of breeding sites were along the middle course of the Vistula river and in the southern part of Poland.     

The river before damming: distribution and ecological notes on the endemic species <Emphasis Type="Italic">Echinogammarus cari</Emphasis> (Amphipoda: Gammaridae) in the Dobra River and its tributaries,Croatia

The endemic species Echinogammarus cari (Karaman 1931) is the only species of this genus present in the Black Sea drainage basin of Croatia. The species is known only from its type locality, the Bistrac spring. Since little is known about the distribution and ecology of this amphipod species, research was conducted to determine the extent of its distribution in the Dobra River and its tributaries, part of which will be flooded on the completion of a 52.5 m high dam in 2009. Sampling was conducted at 10 study sites in the drainage area of the sinking Gornja Dobra and at 19 study sites in the Gojačka Dobra, including measurement of physicochemical parameters. To examine microdistribution of this species, samples were collected on moss and on stony substrate. The species is confined to first 15 km of the Gojačka Dobra, its tributary streams Bistrica and Ribnjak, while it is absent in the drainage area of the Gornja Dobra. At all sites where it was recorded, it coexists with Gammarus fossarum, and its relative abundance was significantly higher on moss microhabitats, while G. fossarum was more abundant on a stony substrate. The downstream decrease in the relative abundance of E. cari could be related to the longitudinal decrease in conductivity and the increase of water temperature fluctuations. After the completion of the dam, 60% of the presently known distribution area of E. cari will be flooded. Consequently, the species is likely to become endangered.     

Long‐term vegetation changes in experimentally grazed and ungrazed back‐barrier marshes in the Wadden Sea

Abstract. Vegetation succession in three back‐barrier salt marshes in the Wadden Sea was studied using a data set comprising 25 years of vegetation development recorded at permanent quadrats. The effect of livestock grazing on succession was assessed by comparing quadrats where grazing was experimentally prevented or imposed. We studied changes at the species level as well as at the level of the plant community. Special attention is given to effects on plant species richness and community characteristics that are relevant for lagomorphs (hares and rabbits) and geese. Inundation frequency and grazing were most important in explaining the variation in species abundance data. The three marshes studied overlap in the occurrence of different plant communities and the observed patterns were consistent between them. Clear differences in frequency and abundance of plant species were observed related to grazing. Most plant species had a greater incidence in grazed treatments. Species richness increased with elevation, and was 1.5 to 2 × higher in the grazed salt marsh. Grazing negatively influenced Atriplex portulacoides and Elymus athericus, whereas Puccinellia maritima and Festuca rubra showed a positive response. The communities dominated by Elymus athericus, Artemisia maritima and Atriplex portulacoides were restricted to the ungrazed marsh. Communities dominated by Puccinellia maritima, Juncus gerardi and Festuca rubra predominantly occurred at grazed sites. As small vertebrate herbivores prefer these plants and communities for foraging, livestock grazing thus facilitates for them.