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Selection of nesting and foraging habitat by the Lesser Spotted Eagle Aquila Pomarina (Brehm) in the Knyszyńska Forest (NE Poland)

Mirski P.

Polish Journal of Ecology

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2009

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Vol. 57, nr 3

581-587

EN

To manage conservation issues, it is essential to recognize the factors determining the occurrence of endangered species. This study examined the foraging habitat and nest site preferences of the Lesser Spotted Eagle Aquila pomarina (Brehm) in the Knyszyńska Forest (NE Poland). This is a large (839 km[^2]) protected (Landscape Park Puszcza Knyszyńska, NATURA 2000) forest complex composed mainly with coniferous and mixed wood stands with meadows in river valleys inside the complex and arable lands outside it. The research was carried out on a study plot of 440 km[^2], in the breeding seasons of 2006 and 2007. Nest site characteristics, such as distance to open areas, settlements and watercourses were measured and compared with random points. The habitat composition of hunting territories was recorded and compared to habitat availability on the whole study plot, and the birds. hunting effort was assessed. The eagles showed a preference for nesting close to open spaces (potential hunting grounds) and watercourses (like rivers and streams), but avoided proximity to human settlements. As hunting grounds, the birds highly preferred grasslands and avoided arable lands. Time spent hunting on grasslands comprised over 95% of the observed hunting activities and grasslands were significantly positively selected both in the whole study plot and within a 2 km-radius from nest. The results suggest that the conservation of the Lesser Spotted Eagle should focus especially on meadows and pastures adjacent to large forest complexes.

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Hunting habitat preferences of raptors in a mountainous area (Northwestern Spain)

Tapia L., Dominguez J., Rodriguez L.

Polish Journal of Ecology

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2008

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Vol. 56, nr 2

323-333

EN

The hunting habitat preferences of six diurnal raptors (see below) were studied during spring-summer and autumn-winter periods in a mountainous area of northwestern Spain (the Baixa Limia-Serra do Xures Natural Park). For this, 15 counting-points were established (at 800 m a.s.l.) in the study area between February 1997 and January 1998. Each point was sampled 4 hours per month. The dependent variables used were presence-absence and specific relative abundance (number of birds hr[^-1]km[^-2]). Seventeen environmental variables (number of settlements, surface area occupied by settlements, road length, minimum altitude, maximum altitude, max-min altitude, mean altitude, min slope, max slope, max-min slope, mean slope, surface area occupied by scrub-pasture, surface area occupied by forest, scrub-forest edge, number of people hr[^-1] km[^-2], livestock hr[^-1] km[^-2], vehicles hr[^-1] km[^-2]) were used as predictors for characterizing the hunting habitat patterns between March and August (spring-summer period) and between September and February (autumn-winter period). Information regarding each independent variable in the monitoring areas was obtained from 1:50000 digital maps. We analysed the habitat selection patterns of six raptor species, using univariate and multivariate analysis. The PCA generated three factors that accounted for 84% of the variance in spring-summer and 81% of the variance in autumn-winter. The Short-toed Eagle Circaetus gallicus (Gmelin) did not show any pattern in their habitat selection. The Hen Harrier Circus cyaneus (L.) and Montagu's Harrier Circus pygargus (L.) were more often observed in higher, more gently sloping areas. The spring-summer abundance of the Common Buzzard Buteo buteo (L.) was positively correlated with the surface area occupied by human settlements and the surface area occupied by forest, and in the autumn-winter period its abundance was negatively correlated with the mean slope. The Golden Eagle Aquila chrysaetos (L.) showed similar hunting habitat selection patterns in both periods, with a preference for shrub areas and weak presence of human settlements. The Common Kestrel Falco tinnunculus (L.) did not show any pattern of habitat selection in the spring-summer period but its abundance was negatively correlated with the mean slope in the autumn-winter period.

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Effect of felling on the distribution of rodents and their predators in a transitional mixed forest

Sidorovich V., Solovej I., Sidorovich A., Rotenko I.

Polish Journal of Ecology

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2008

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Vol. 56, nr 2

309-321

EN

The influence of felling on the distribution of rodents and their predators in a transitional coniferous-deciduous forest in northern Belarus was investigated in relation to stand age, forest type, and soil richness. The study was conducted in two areas differing by top-grounds (clay and sand soils) and, in turn, having different habitat carrying capacities. Three forest parts were investigated: 1) 10%, 2) 20-30%, and 3) 40-60% covered by recent clearcuts. Three age classes of the clearcuts, namely 1) less than 2 years old, 2) 2-5 years old and 3) 6-12 years old, were considered. In total, we obtained data on small rodent numbers in 84 clearcuts, and the data on predators - in 67 clearcuts and the woodland parts differed by logging rate. Eventually, we became convinced that felling generally led to an increase in the abundance and species richness of rodents and their predators and that was attributable in the clearcuts aged up to 12 years. First, logging led to higher densities of Apodemus mice, the red fox Vulpes vulpes L., weasel Mustela nivalis L., tawny owl Strix aluco L., common buzzard Buteo buteo L. and adder Vipera berus L. Also, with the increased felling rate Microtus voles and the longeared owl Asio otus L. penetrated in transitional woodlands. Too intensive forest harvesting (more than 40% of recent clearcuts) led to the decline in the populations of several predatory species such as the pine marten Martes martes L., Tengmalm.s owl Aegolius funereus L., Ural owl Strix uralensis Pall., and pygmy owl Glaucidium passerinum L. The decline in rodent predators found in the conditions of too intensive logging rate was different in the woodlands on sand and clay top-grounds. In the conditions of clay soil too intensive felling led to the pronounced decline of a marked part of the rodent predatory guild inhabiting woodlands, and the species densities decreased to the level that was lower than the initial one. Conversely, in initially poor habitats in the woodland on sandy deposits, logging of any rate led to the increase in numbers of rodents and their predators compared to undisturbed forest. But moderate logging was found to be the most favourable for the community there.

4

Content of heavy metals in bodies of field ground beetles (Coleoptera, carabidae) with respect to selected ecological factors

Purchart L., Kula E.

Polish Journal of Ecology

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2007

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Vol. 55, nr 2

305-314

EN

The concentration of heavy metals in the bodies of invertebrates is dependent on their physiological equipment and prevalent environmental factors. To verify the effect of some of these factors on the content of metals (Pb, Cd, In, Cu, Mn) we analysed and then tested (using RDA, t-test) ten species of field ground beetles (Coleoptera, Carabidae). A significant effect of Cu and Cd was discovered in terms of the sex; the males accumulated more Cu (27.520 mg kg[^-1]) than females (18.297 mg kg[^-1]) (P <0.01), which, on the contrary, accumulated more Cd (1.495 mg kg[^-1]) than males (0.663 mg kg[^-1]) (P <0.02). The content of all the metals differed significantly (P <0.03) according to the species, unambiguously showing species-specific models of accumulation. The effect of the feeding ecology was evident only on the essential elements; carnivores (Zn - 222.596 mg kg[^-1], Cu - 27.211 mg kg[^-1], Mn - 71.929 mg kg[^-1]) had a significantly (P <0.03) higher contents than omnivores (Zn - 168.198 mg kg[^-1], Cu - 21.116 mg kg[^-1], Mn - 58.452 mg kg[^-1]). Although there were differences (P <0.01) in the concentrations of Zn and Cu between the spring (Zn -163.749 mg kg[^-1], Cu - 19.998 mg kg[^-1]1) and autumn (Zn - 202.373 mg kg[^-1], Cu - 25.496 mg kg[^-1]) species, the effect of the type of reproduction is considered to be only partial. At the same time the time of sampling affected the Zn and Mn (P <0.02) content. An important positive correlation was determined between the contents of Cu-Zn, Mn-Zn and Mn-Cu.

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Chore i okaleczone zwierzęta jako ofiary pasożytów i drapieżców w jurze Polski - przegląd stanu wiedzy

Radwańska U., Radwański A.

Volumina Jurassica

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2004

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Vol. 2, no. 1

99-112

EN

The parasitism of, and predation upon, the diverse Middle and Late Jurassic invertebrates of Poland, personally recognised by the authors, are reviewed. All cases are discussed either in the biological (anatomical, ethological), or ecological terms, to show the mode of infection, or injury, and the relationship between the engaged taxa. The preys to parasites are exemplified by the prosopid crabs infested by bopyrid isopods, the crinoids infested by myzostomid polychaetes (both disk-shaped, and wormlike), and the echinoids attacked by copepod arthropods involving either swellings of spines, or gall-shaped cysts upon the test outerly. Of traumatic events, discussed is regeneration of injuries in the belemnite hooked guards, and in the ammonite shells of distorted ribbing. The pearl-like structures in belemnite guards (the “belemnite pearls”) are interpreted as caused by a tiny parasite encapsulated during further growth of the belemnite. Heaps of ammonite shell hash are thought to represent the ,“kitchen middens” of a larger predator which has feasted upon the fleshy tidbits alone, the beaten shell having been left. The post mortem damage of shells is remarked (taphonomic feedback and/or aftermath) to be distinguished from that one acted in shells of alive specimens of the Middle and Late Jurassic of Poland.