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With the aim of quantitatively evaluating the usefulness of phyllostomid bats as ecological indicators, we compared intra-family levels and feeding guilds between tropical old-growth forest and patches of secondary vegetation growing where the land had been used for shifting agriculture. There were significant differences between vegetation types in bat species composition, with the frugivore guild most abundant in secondary vegetation and the animalivore guild most abundant in the old-growth forest. These results are congruent with the findings for other Neotropical zones and appear to be associated with the type of soil management that allows secondary vegetation to grow. Using the Indicator Value method, two subfamilies, five genera and five species were found to have a significant indicator value. However, these numbers only represent a small proportion of the five subfamilies, 20 genera and 28 species recorded, indicating that under the disturbance conditions that characterize the study area, phyllostomid bats were poor ecological indicators. Even so, some species and subfamilies are useful as disturbance detectors.
We examined changes in the assemblage of bats in southern Lower Michigan, USA, using results of paired netting surveys conducted with similar techniques but separated by 12–26 years. Species diversity declined by 18–35% and evenness decreased by 0–35% throughout the region and in two specific areas. Changes in diversity and evenness were attributed primarily to decreases of 44% or more in relative abundance of the foliage-roosting eastern red bat (Lasiurus borealis). Number of L. borealis captured per net-night decreased 52–85%. The decline in relative abundance of L. borealis suggested by mist netting was supported by a 10-fold decrease over 38 years in the proportion of L. borealis that were tested for rabies by the state health laboratory. The apparent decline in L. borealis is especially alarming in light of the recent upsurge in use of wind power and the large number of L. borealis that are killed at such developments. We recommend that other previously completed surveys in eastern North America be duplicated, as one way of helping to confirm or refute the trend that we have identified.
The presented paper analyses the occurrence of dragonflies in the left-bank (Polish) part of the Bug River valley between Włodawa and Kodeń (65 km of the river course, 51°32’–51°55’ N, 23°31’–23°38’ E). In total, 40 species were recorded. The key sites for dragonflies were oxbow lakes, the Bug River and its tributaries. Species diversity was found to be relatively low due to a lack of peat lands and dystrophic waters, as well as strong astatism of small water bodies. The effects of strong water pollution in the Bug River were evident. The species composition of dragonflies was typical, but densities of Gomphidae (particularly Ophiogomphus cecilia ) suggested an adverse state of the environment. This is caused by surface runoffs of agricultural wastewater in Poland, but also by strongly polluted rivers in the territory of Ukraine. The study includes a review of earlier research conducted in the upper course Bug River valley. Considering both the old and new data, 54 dragon fly species were recorded in the Middle Bug River valley between Gołębie and Kodeń (246 km of the river course at the border of Poland with Ukraine and Belarus). It is an area of high importance for the protection of dragonflies in terms of species diversity and species assemblages.
The aim of this paper was to identify the relationship between the degree of macrophyte cover on the lake bottom and the abundance and species richness of larva and juvenile stage assemblages. The analysis of the material verified the hypothesis that as the surface area of macrophyte cover increases so does the abundance, species richness, and diversity of fish aggregations. The investigations were conducted in the heated Lake Licheńskie in 2000-2003 during the period when underwater vegetation is at the height of development (June – September). The spatial differentiation of macrophyte occurrence had a significant impact on the occurrence and differentiation of the fry assemblages. It was confirmed that along with an increase in the macrophyte cover surface area there was also an increase in the species richness and diversity of juvenile fish assemblages. The locations that were most densely overgrown with vegetation had the highest fish biomass and individual weight. In littoral areas without macrophytes, abundant single-species concentrations of fish occurred. The bottom macrophyte cover did not have an impact on the numbers of fish.
Farmland bird populations declining rapidly all over Europe. Most of the knowledge is, however, from the breeding season, and much less is known about the winter period, especially from Central and Eastern Europe. We censused wintering farmland bird assemblages in West Hungary, in 2011/2012. The censuses covered semi-natural and seeded grasslands, plough fields and wheat fields. The available winter seed food was estimated for each field from the top soil and from the vegetation. We recorded 25 species with 844 individuals on the fields. Semi-natural grasslands were the most important habitats for species richness of all, granivorous, and resident species, with seeded grasslands as the second best habitat. Abundance showed similar pattern, although with no significant effect for granivorous species and for short-range migrants. Seed mass was significantly different among the habitat types, higher on seeded grasslands and seminatural grasslands than on ploughed sites and winter wheat fields. Date had a significant effect on species richness and abundance with highest values in December. There was a positive significant correlation between bird species richness and seed mass only in December. Our results strengthen former findings that changes and drivers of wintering farmland bird populations may differ between Central and West Europe, and highlight the need for further, large scale studies to provide evidence base to guide agrienvironmental programs.
Giardia intestinalis is a complex species divided into 7 assemblages (A – G). Two of them (A and B) are infective for both humans and animals. In cats four assemblages can occur: A, B, D, and F. Assemblages A and B infect either cats, dogs and humans, assemblage D infects cats and dogs and assemblage F only cats. The purpose of this study was to determine the prevalence and genotypes of G. intestinalis in cats from Warsaw. From November 2006 to March 2007 a hundred sixty samples of stool were collected and examined by light microscopy. G. intestinalis cysts were detected in 3.75% of samples. DNA extracted from positive samples was used as template for PCR-RFLP using Giardia specific primers and the amplicons were sequenced. A comparison of the obtained DNA sequences with the Giardia sequences in the GeneBank database revealed assemblage A in 1.25% of the investigated cats, assemblage B in 1.25% and D in 1.25%.
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