Osowiec Twierdza, Poland
Osowiec Twierdza, Poland

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Kloskowski J.,Maria Curie Sklodowska University | Kloskowski J.,University of Life Sciences in Poznań | Tanneberger F.,University of Greifswald | Marczakiewicz P.,Biebrza National Park | And 2 more authors.
Ibis | Year: 2015

To identify optimal habitat for the Aquatic Warbler Acrocephalus paludicola, a flagship species of fen mires, we related numbers of singing males to habitat variables in all core breeding sites in eastern Poland. The density of male Aquatic Warblers increased with increasing ground cover by water and mosses and litter layer height, and was highest where vegetation was 60-90 cm tall. Male densities also increased with the biomass of arthropods > 10 mm length, estimated by sweep netting, and with the abundance of spiders, estimated by pan trapping. We suggest that habitat management should take into account species-specific morphological adaptations, nest safety and arthropod productivity. Prevention of vegetation succession is a conservation priority for open fen mires. However, modern management practices to achieve this, especially mowing using tracked vehicles, should be evaluated and optimized to ensure that such practices do not adversely affect the long-term development of moss cover and litter structure. © 2015 British Ornithologists' Union.


Krzysztofiak L.,Wigry National Park | Krzysztofiak A.,Wigry National Park | Frackiel K.,Biebrza National Park | Biala A.,University of Gdansk | And 2 more authors.
European Journal of Entomology | Year: 2010

This is the first study of the morphological and molecular variation in two peripheral populations of the butterfly Jutta Arctic, Oeneis jutta, a glacial relict species endangered by the fragmentation of its habitat in Poland. An analysis of the morphological characteristics indicates that both Polish populations are similar but differ significantly in some characteristics. Levels of genetic variation were assessed using mitochondrial cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 5 (ND5) gene fragments together with a segment of the mtDNA control region (CR) and a nuclear elongation factor-1α (EF-1α) gene sequence. In addition, the pattern of molecular variation in specimens from eastern and northern Europe was examined. Interestingly, the analysis of variation in a 932-bp sequence of the nuclear EF-1α gene in representatives of the populations studied revealed a relatively higher level of diversity than that of mitochondrial genes. There was evidence of divergence between the peripheral populations and lack of gene flow between them. The two closely situated populations had a high ΦST value (0.69), which clearly indicates their isolation. These populations appear to be demographically independent breeding units, with distinctive allele frequencies and consequently should be recognized as separate units for management and conservation. The preliminary results are in accord with an a priori subdivision based on collection areas and suggest that habitat fragmentation has affected the genetic diversity and structure of these populations. © 2003 Institute of Entomology.


Kotowski W.,University of Warsaw | Jablonska E.,University of Warsaw | Bartoszuk H.,Biebrza National Park
Biological Conservation | Year: 2013

Cessation of traditional mowing management has been the main threat to fen biodiversity for many decades; shrubs and trees expand and target plant and animal species decline. In Biebrza National Park (BNP), the EU's largest conservation area of alkaline fens, abandonment has affected more than 300km2. To combat unwanted succession, tracked mowers were developed based on snow grooming vehicles and are increasingly used in BNP and some other European fens. While effects on bird populations seemed promising, the impact on botanical diversity remained yet unknown. We assessed the effects of this management on vegetation by comparing 12 pairs of mown and unmown plots (percentage cover recorded from 4m2 for all species and 25m2 for rare species) spread over several km2. We found that tracked vehicles suppressed some species, which are likely to facilitate others by providing shelters above groundwater level (hummock mosses, tussock sedges and shrubs) and enhanced species with effective clonal spread and high specific leaf area. An even stronger increase was observed in forbs, which share effective clonal spread and flood tolerance (high Ellenberg F value). Analysis of functional diversity indices based on all measured traits showed a decrease of functional divergence due to mowing (indicating convergence of traits) and no response of functional richness, evenness and functional dispersion. Mowing has also decreased the number of rare species. We associate these changes with the reduction of micro-topography by caterpillar tracks. Tracked mowers should therefore be avoided in those fens, in which microtopography contributes to unique botanical diversity. © 2013 Elsevier Ltd.


Lenard T.,Catholic University of Lublin | Ejankowski W.,Biebrza National Park
Hydrobiologia | Year: 2016

The effect of long-term changes in total precipitation on physical and chemical parameters of the water and the structure of phytoplankton community during a year were studied in a deep hard water lake. With respect to total precipitation, two different periods were distinguished: dry and wet. In the wet period, the water level rose and caused an increase in the water colour and a decrease in the electrolytic conductivity and concentration of nutrients. These changes were reflected in the composition and amount of phytoplankton. Certain phytoplankton groups, e.g. Cryptophyceae, Dinophyceae, Chrysophyceae, Bacillariophyceae and Chlorophyta/Charophyta, were positively affected by the environmental changes; instead, these effects were not observed in Cyanobacteria and Euglenophyta. The development of flagellates, such as Cryptomonas curvata, Plagioselmis nannoplanctica and Ceratium hirundinella, was enhanced during the wet period, whereas the dry period favoured non-flagellates, such as Planktothrix agardhii, Planktothrix rubescens and Limnothrix planctonica. Hence, the long-term variability in total precipitation can be a switch from non-flagellate- to flagellate-dominated phytoplankton in lakes. Moreover, a short time of ice cover duration in winter linked with the wet period promoted phytoplankton groups typical for spring and autumn, e.g. Cryptophyceae and Bacillariophyceae. © 2016 Springer International Publishing Switzerland


Grzywaczewski G.,Lublin University of Life Sciences | Osiejuk T.S.,Adam Mickiewicz University | Cios S.,Lublin University of Life Sciences | Marczakiewicz P.,Biebrza National Park
Annales Zoologici Fennici | Year: 2014

We investigated the microhabitat characteristics of song posts used by males of the aquatic warbler in Biebrza National Park (Poland). On average, song posts were located at a height of 94 cm and 32 cm from the top of the plant. Males preferred singing from living plants in habitat patches with tall vegetation and a low water level. The only factor significantly affecting the place chosen for singing was vegetation height, and males sang from a higher location as vegetation height increased. Where only lower vegetation was available, males used relatively higher places for singing in comparison with the total plant height. These observations support the hypothesis predicting the optimization of song post height. © Finnish Zoological and Botanical Publishing Board 2014.

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