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Abundance of red fox (Vulpes vulpes) populations in Poland and Europe have increased in the past decades, especially in the areas of high anthropogenic transformation. The aim of this study was to assess the current density of red fox in natural forests and to analyse changes in its abundance since 1981. The fieldwork was carried out in Polish part of the Bialowieża Primeval Forest (BPF), including Białowieża, Browsk and Hajnówka forest districts as well as Białowieża National Park. A standard method of snow tracking along transect routes (15 to 94 km long in the subsequent winters, altogether 199 km) was used. Taking a density of snow tracks per 1 km of a transect route per 24 h and the length of daily movements of red foxes (13,8 km) we calculated the population density. Results were compared with historical data derived with the same method. Mean number of tracks of red fox in the years 2011−2016 equaled 6.1/km/24h (SD=3.9). Density of fox population was 0.69 individuals/km², which results in the abundance of the population in the whole area of BPF of 414 individuals in winter time, while of approximately 869 individuals in spring. Comparison of current data with the results from last three decades showed an increasing trend in the population of the analysed species. Nevertheless, in comparison to central or western Poland the density of the red fox in the BPF is still relatively low. Possible factors that suppress this population are parasites, infections (mange, rabies) and large carnivores.
Analyses of 69 collections of the tawny owls' pellets (28 containing over 100 prey items) revealed the presence of three rare mammal species on several localities in central and northeastern Poland: Muscardinus avellanarius (11 localities), Sicista betulina (3), and Crocidura leucodon (2). The obtained results supplemented data on their distribution close to the borders of continuous ranges. The Kampinos Forest was confirmed as important refuge of M avellanarius, and the lower basin of the Biebrza Valley for both M. avellanarius and S. betulina.
The analysed pellet material was collected in the years 2014-2015 in the forest complex Prusy, a part of Rogów Forest District. Diet of owls was dominated by voles Microtus spp., accounting for 76% of prey items. The contribution of Muridae was 13% and the total contribution of rodents was close to 90%. Common shrews, birds and insects supplemented the diet.
Rozpoczęty w latach 70. i kontynuowany do dnia dzisiejszego monitoring ptaków szponiastych na terenie Nadleśnictwa Rogów pozwala śledzić trendy liczebności wybranych gatunków. Ostatnia całościowa inwentaryzacja przeprowadzona w latach 2001-2003 ujawniła znaczne zmiany liczebności myszołowa, jastrzębia i kruka. O ile wzrost zagęszczenia myszołowa i kruka pozostaje w zgodzie z ogólnokrajowym trendem liczebności tych gatunków to znaczny spadek zagęszczenia jastrzębia budzi niepokój i skłania do poszukiwań środowiskowych i/lub antropogenicznych przyczyn tych zmian.
Data on sex structure and growth of the population is crucial for proper game management. Camera traps, which are of reasonably low cost, but very efficient, can potentially measure the aforementioned parameters. The paper objectives was to assess the share of bucks, does and calves in red deer Cervus elaphus population in the area of the Białowieża Forest. Two methods were used: camera traps and a traditional method of all−year−round observations. The study was conducted in the years 2011−2015 in three forest districts and the Białowieża National Park. Reconyx trail cameras were exposed in one location for approximately 30 days, then moved to a new place. Altogether, trail cameras were exposed in 761 spots, at least 500 m apart one from another. Analyses were based on material collected between June 1st to September 31st when sex and age identification were the most reliable and hunting season had yet not started. Additionally, all−year−round observations of animals were done by foresters and scientists in the whole forest area, species, sex and age were noted in the special forms. The number of observers was similar to that of exposed trail cameras. Sex and age structure of red deer population changed between years, but according to both methods does were more numerous than bucks. According to trail cameras, share of bucks was on average 42 vs. 32% (data for all years combined), and a population growth was 39−60 calves/100 does, depending on a year. According to all−year−round observation, share of bucks was 26%, of does 53% and there were 37 calves/100 does. The dominance of does over bucks is difficult to explain as the sex structure at birth is 1:1. The does are more susceptible to predation and are culled more often. As data from trail cameras showed lower disproportion, we may assume that those results were more reliable. Trail cameras can collect data all the time, regardless the season, time of a day and weather conditions. Pictures can be analysed in details and observations verified if necessary. Their biggest disadvantage is price (especially when we assume that all−year−round observations can be done as a part of work duties by forest service), and risk of theft or damage.
Zmiany zachodzące w środowisku przyrodniczym powodują zanikanie wielu populacji rodzimych drobnych ssaków i sprzyjają równoczesnej ekspansji gatunków obcych. Trudności w monitoringu tej grupy wynikają z ich niewielkich rozmiarów oraz zmierzchowo-nocnego trybu aktywności. Stosowanie podstawowych metod badawczych takich jak pułapki żywołowne i zabijające, od dawna budziło zastrzeżenia zarówno etyczne jak i metodologiczne. Metoda alternatywna, czyli analiza wypluwek sów, bazuje na hipotezie, iż skład pokarmu drapieżników oportunistycznych odzwierciedla pod względem ilościowym oraz jakościowym zgrupowanie drobnych ssaków na terenie, gdzie zebrano analizowany materiał. Najłatwiej dostępne i stosunkowo mało skomplikowane w opracowaniu laboratoryjnym są wypluwki puszczyka Strix aluco. Gatunek ten zaliczany jest do najmniej wybiórczych środowiskowo sów występujących w Polsce, wykazuje typowo nocny typ aktywności, jest oportunistą pokarmowym oraz poluje na szerokie spektrum ofiar. Bardzo ważnym aspektem jest również terytorializm puszczyków. Wielkość zajmowanego obszaru zależy do żyzności siedliska i zawiera się w przedziale od kilkunastu do kilkudziesięciu hektarów. Mamy więc pewność, iż ssaki, których szczątki znajdziemy w wypluwkach, zostały upolowane w promieniu kilkuset metrów od miejsca gniazdowego.
W dniu 2 kwietnia 2012 roku w Puszczy Białowieskiej (Nadleśnictwo Białowieża, oddział 520A) obserwowano zająca bielaka Lepus timidus. Jest to jedno z niewielu udokumentowanych stwierdzeń tego gatunku w Puszczy Białowieskiej
The aim of this study was to assess the density and diet composition of free-ranging dogs in Poland. The study was conducted in a field and forest mosaic in the central part of the country in the years 2005–2011. The density of the free-ranging dogs was assessed during night counts along repeated transect routes. The number of dogs seen and the feasible observation area were recorded to calculate density index for each control. The day and night counts captured data on group composition and penetration range. Diets were studied through scat analyses. The dog density ranged from 2.2–3.1 ind. km–2 depending on the area. Most dogs were observed alone, and 40% formed groups of 2 to 5 dogs. Most groups were recorded close to buildings, but the group organisation changed (especially during the daytime) with increasing distance from the buildings: 35% of dogs in the village were in groups, but 55% of dogs formed groups at a distance of more than 100 m from the buildings. The night proportion of dogs in groups was approximately 50%, regardless of the distance. Their scats contained mostly cereal given by farmers. The prey remains were game species: roe deer (1.3% of occurrences in summer and 12% in winter), brown hare (3–4%), small mammals (5–9.5%) and birds (approx. 1.5%). The study demonstrated that the abundance of dogs in the rural areas of central Poland may play an important role in the ecosystem.
The aim of the study was to characterize the diet composition of tawny owl in relation to environmental variables: season and availability of small rodents. Study area was located in central Poland, in Łódź voivodship, in the area of Rogów Forest District. It comprised of a mosaic of forests and arable lands. The study was done in the years 2003−2010. Pellets were collected at least twice a year in 18 tawny owl territories. Material collected between April and September was categorised as coming from spring−summer, while this from October−March period as autumn−winter season. Simultaneously, in the years 2004−2007, changes in the number of small rodents were monitored by live−trapping. Standard procedures of pellet analyses were used to identify 1926 prey items. Generally, diet composition was dominated by small rodents. Yet, their share was significantly higher in autumn−winter season (71.3 vs. 57.3%). Among rodents, yellow−necked mice, common voles and bank voles were caught most often. Soricomorphs accounted for 3% of prey items in both seasons on average. Birds formed approximately 15% of prey items and their share was comparable in warm and cold half year. On the other hand, in a warmer period owls preyed on invertebrates more often (23.0 vs. 7.5%). A breadth niche was wider in a warm (D=4.01) half year than in cold one (D=3.36). When a peak of rodent number was recorded, owls preyed on bank voles twice as often as compared to other years (increase from 6.4 to 11% of prey items), while an increase in the consumption of yellow−necked mouse was lower (from 27.5 to 34.2%). Tawny owls preferred yellow−necked mice and bank voles were avoided. This study showed that in the Rogów Forest tawny owl is an opportunistic predator. However, composition of its diet does not absolutely reflect the structure of assemblage of small mammals as certain species are preferred.
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