scholarly journals Pigeon and Poultry Breeders, Friends or Enemies of the Northern Goshawk Accipiter gentilis? A Long-Term Study of a Population in Central Poland

Animals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 141 ◽  
Author(s):  
Jakub Gryz ◽  
Dagny Krauze-Gryz
Keyword(s):  
Diet Composition ◽  
Prey Availability ◽  
Published Data ◽  
Current Time ◽  
Breeding Parameters ◽  
Small Game ◽  
Central Poland ◽  
Long Term Study ◽  
Forest Mosaic

In this study, we focused on a goshawk population in central Poland (study area 105 km2,forests 24 km2, seven small forest complexes) which was monitored long-term (with high densitiesrecorded in the 1980s of 16.3 pairs/100 km2 despite persecution by farmers) to analyse howenvironmental factors (prey availability and changes in the forest structure) influenced populationabundance, breeding parameters, and diet composition. The study was undertaken from 2011–2018,and the results were compared with published data from two previous study periods (1982–1992and 2001–2003). The number of breeding pairs dropped from 17.1 to 8.0; the breeding success wasaround 75% in all study periods. The selection of nesting trees followed the changes in stand speciesand age structure. More nesting attempts per one nest were recorded in the current time period (1.7 vs.1.1), which probably reflected lower anthropopressure (i.e., no cases of persecution were recordedin this study). Diet composition seemed to follow changes in the prey availability: The share ofdomestic pigeons and poultry (the main prey in the 1980s) as well as small game dropped, whilethe share of Eurasian jay and wood pigeon increased. Our studies suggested that anthropogenicfood (poultry and domestic pigeons) played a key role for the goshawk population in thetransformed habitats of the field and forest mosaic.

scholarly journals Food Niche Overlap of Avian Predators (Falconiformes, Strigiformes) in a Field and Forest Mosaic in Central Poland

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 479
Author(s):  
Jakub Gryz ◽  
Dagny Krauze-Gryz
Keyword(s):  
Diet Composition ◽  
Prey Availability ◽  
Niche Overlap ◽  
Breeding Period ◽  
Central Poland ◽  
Avian Predators ◽  
Forest Mosaic ◽  
Field Rodents ◽  
Food Niches ◽  
Food Niche

Food niche overlap statistics are a common way to show competition for food resources in a group of animals. Niche breadths of various species are very variable and their diet composition changes reflecting prey availability. The aim of this study was to evidence the food niche overlap of the whole assemblage of avian predators (eight raptor and owl species, some of them reaching very high densities) in a field and forest mosaic of central Poland. The diet composition was assessed on the basis of pellet analyses and the identification of prey remains found under the nests in the breeding period. The extent of the niche overlap was calculated using a Pianka formula. The food niche overlap indices ranged from 0.02 to 0.93 (mostly below 0.5). The most separate food niche was that of the white-tailed eagle, who regularly preyed on fish. The highest niche overlap was recorded for the common buzzard and common kestrel, two species preying on field rodents, switching to soricomorphs when the former were scarce. Our results confirmed that the food niches of species coexisting in the same area were considerably separate, which is a result of preying on various prey species or searching for them in different habitats.

scholarly journals On the vertical growth of continents in deep depressions of the Earth’s peridotite mantle

LITOSFERA ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 727-745
Author(s):  
A. M. Zhirnov
Keyword(s):  
Sedimentary Basins ◽  
Geological Structure ◽  
Published Data ◽  
Term Study ◽  
Long Term Study ◽  
Large Size ◽  
The Earth ◽  
Peridotite Mantle ◽  
Archean Basement

Research subject. The geological structure and evolution of the Earth’s continents.Methods. This article is based on a long-term study and review of geological, geophysical and bathymetric published data, as well as on an analysis of the major geological discoveries of the 20th century.Results and conclusions. It is established that all the continents on the Earth, except for Antarctica, constitute a single Northen megamaterik, which was being formed during a prolonged period of time (4.4 billion years) in a deep three-beam cavity on the surface of the peridotite mantle. The ancient Hadean– Archean basement of the megacontinent was being formed during the period of 3 billion years, which comprises about 70% of the Earth’s geological history. In the Late Proterozoic and Phanerozoic, periodically formed local depressions were flooded with sedimentary material leading to the formation of sedimentary basins and folded rock structures. As a result, the thickness of the megacontinent’s crust steadily increased reaching a large size of 15–40 or 60–70 km. During this period, the primary oceanic (peridotite) crust with a thickness of 3–5 km remained unchanged until the Mesozoic–Cenozoic, when it was covered with a layer of younger basalts and loose rock sediments with a thickness of 1–2 km.

scholarly journals The Common Buzzard Buteo buteo Population in a Changing Environment, Central Poland as a Case Study

Diversity ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 35 ◽  
Author(s):  
Jakub Gryz ◽  
Dagny Krauze-Gryz
Keyword(s):  
Diet Composition ◽  
Stand Structure ◽  
Small Rodent ◽  
Breeding Parameters ◽  
Bird Of Prey ◽  
Common Buzzard ◽  
The Past ◽  
Central Poland ◽  
The Common

Common buzzard is the most abundant bird of prey in Europe, and its population has undergone serious changes. In this study, we focused on a population in Central Poland (study area 105 km2, forests around 24 km2, seven forest complexes) to analyze how certain environmental factors influenced population abundance, breeding parameters, and diet composition. The study was undertaken from 2011 to 2018, and the results were compared with data from two study periods (1982–1992; 2001–2003). Current population density was 3.5 pairs/10 km2 of total area and 14.3 pairs/10 km2 of forested area, it was negatively correlated to the abundance of northern goshawk, and it grew in the last few decades. Mammals were dominant prey (72.6% prey items, 38.6% of biomass), but their share in diet changed following rodent availability. A decrease in the share of voles was recorded, reflecting drop in their abundance and dampening of abundance cycles. Breeding parameters were similar to those in the past, and the number of offspring depended on small rodent availability. Buzzards adapted to changes in the stand structure, i.e., when share of Scots pine decreased, they chose it as their nesting tree less frequently. All this showed that buzzard is a very adaptable species.

Quinapril for Sclerosis Failed in Long-Term Study

2007 ◽  
Vol 38 (6) ◽  
pp. 14
Author(s):  
DAMIAN MCNAMARA
Keyword(s):  
Term Study ◽  
Long Term Study
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