Abstract: We performed an analysis of data on direct observations of wolves and their traces carried out by forest service employees, hunters, naturalists and local residents in areas supervised by eight Regional Directorates of State Forests (RDSFs) and in two National Parks located in Western Poland. The study area covered a major part of Western Poland, with the exception of RDSFs in Toruń and Łódź. The aim of the study was to determine the frequency and location of direct observations of wolves and their traces. Additionally, all reports on the prey of this predator were analysed. A mobile application was used to collect the following information: the date and time of observations, the location of observations with geographical coordinates, the number of wolves encountered during the direct observations of these animals and their tracks, wolf breeding sites, wolf prey, and vocalizations. A short description of the observations and photographic documentation were included in the analysis as well. In total, 5664 records on the occurrence of wolves were collected in 2019−2022. The most abundant information about these animals was collected in the autumn−winter months, whereas a significantly lower number of data was recorded in the summer period. Single wolves were observed most frequently, followed by wolf pairs. The average number of individuals in a family group was 3.22, with 3.34, 2.98, 3.25, and 3.32 observed in the respective study years. Wolf packs composed of at least three individuals accounted for only 20.8% of the direct observations. Wolves and their traces were found in each Regional Directorate of State Forests and the two National Parks. The greatest number of records was reported from RDSFs in Szczecinek, Gdańsk, and Katowice, while the lowest number was found in RDSF in Zielona Góra. The distribution of wolves coincided with the presence of large forest complexes. These animals and their tracks were observed more frequently in counties with large forest cover and less often in counties with high population density. The study indicated that not all habitats typical for this species were occupied during the recolonization process. The reports have also shown that red deer (58%) and roe deer (23%) were the most common wolf prey, whereas livestock (6%), fallow deer (6%), and wild boars (5%) were attacked by wolves less frequently. The analysis of the data has indicated that wolves still occupy areas with the largest forest cover but are only occasionally encountered in less favourable environments. The majority of the records reported the presence of single wolves that may have been non−resident individuals or members of wolf packs searching for prey animals alone, especially in spring and summer.
Key words: Canis lupus, distribution, prey, Western Poland, wolf

Abstract: The subject of this article is the issue of unlawful felling of trees in the forest. In Poland, trees growing in the forest are under special protection of criminal law. The author’s intention is to analyse and evaluate the regulations of Polish criminal law sensu largo (covering crimes and petty offences) concerning the issue of unlawful felling of trees in the forest. The author examines when the perpetrator of unlawful felling of trees in the forest commits a crime and when a petty offence, and determines what type of crime or petty offence is involved. The author also determines what actions the behaviour of the perpetrator of the prohibited act in question may involve and checks whether the term ‘forest theft’ used in the context of this act is adequate. The aim of the analysis is also to examine whether the owner of the forest can fell trees in the forest belonging to him without any restrictions. The author begins the analysis by explaining the concepts of ‘forest’ and ‘forest land’ and distinguishing a tree from wood. Then the author analyses the issue of felling trees in someone else’s forest, starting with felling for the purpose of misappropriation. The author explains the term ‘felling’ and refers to the name ‘forest theft’. Next, the issue of felling trees in one’s own forest is addressed. In the following part of the article, the measures of criminal reaction that threaten the perpetrator of felling trees in the forest are presented. At the end of the article, the author presents final conclusions. Using a formal−dogmatic research method, the author analyses the relevant provisions of the Penal Code and the Petty Offences Code as well as the literature on the subject and case law. The author also refers to the provisions of the Forest Act, the Act on the Protection of Agricultural and Forest Lands, and the Act on the Protection of Nature. As a result of the analysis, the author makes several de lege ferenda postulates regarding the amendment of the Penal Code and the Petty Offences Code as well as the Forest Act.
Key words: criminal law protection, Forest Act, hybrid offence, misappropriation, Penal Code

Abstract: Black cherry is an invasive alien plant species that has spread throughout Europe. Various methods are used to control its population including the removal of Prunus serotina biomass from forests. Black cherry trees bear fruit at a remarkably young age, usually between 3 and 5 years old, and produce an abundance of small black fruits that resemble cherries. Harvesting these fruits can help reduce the growth of the population. Harvested fruits can also be processed to extract valuable secondary plant substances, especially phenolics. This study compares the success of one and two week ethanolic extraction methods of black cherry fruit from two growing locations. To determine the content of bioactive compounds in fruit, the biomass fruit was extracted in ethanol solution. Following extraction, the content of bioactive compounds was determined using high−performance liquid chromatography (HPLC) equipped with two detectors. A mass spectrometry detector (MSn) was used for qualitative analysis, while a diode array detector (DAD) was employed for quantitative determination. In total between 8614 and 10780 µg/mL of phenolics were extracted. The results show that the content of some groups of phenolics was influenced by time, namely flavonols and anthocyanins, while the content of flavanones and derivatives of hydroxycinnamic acid was influenced by the location of the harvest. When the fruits were soaked in alcohol for two weeks, the content of cyanogenic glycosides was not influenced by time or location. Cyanogenic glycosides content after two weeks of soaking in alcohol ranged from 31.6 to 32.9 µg/ml.
Key words: bioactive compounds, cyanogenic glycosides, extraction, invasive alien plant species, Prunus serotine

Abstract: Interpretive signs located on educational trails are key to conveying important and interesting information to visitors. Along with sparking park visitors’ interests and inspiring them, interpretive signs create a sense of community and increase care for their surroundings as they help to explain the need to protect cultural and environmental heritage. Sometimes however, these objectives are not fully achievable due to low visitor interest. Observing the behaviour of users of educational trails provides a basis for assessing the validity of the trail’s operation. It prompts reflection on the effectiveness and attractiveness of educational messages. This paper presents the results of an experiment conducted in the field during the summer of 2022, using a photo trap to record the behaviour of users of the educational route. The experiment covered one of the signs on the educational path, ‘Goździkowe Bagno’, in the Celestynów Forest District. The results show that the path users’ genders were near equal between women and men. Most users were adults, visiting the forest in groups of 2 people on foot. Only one in three trail users chose to read the interpretive signs. The largest group (36.07%) of visitors spent 6−20 seconds of their attention on the board. Only 7.16% of the audience fully read the content presented. A statistically significant relationship was found between gender and age, visitor group size, and interest in the educational board. Women were more frequently interested with the content of the interpretative sign than men. Among users who ignored the board, there were significantly more young people than adults. Most senior group users were fully familiar with the board’s content. Visitors who expressed the greatest interest in the content of the interpretative sign were in groups of three. At the same time however, people walking alone showed more commitment to learning about the sign’s content (longer time spent in front of the sign). The experiment’s results may help forest land managers develop strategies for effectively incorporating and managing interpretive signage at naturally valuable sites.
Key words: community forests, educational infrastructure, environmental education, forest visitors, interpretive signs

Abstract: This paper examines annual trends in forest fire events and forest fire hazard indices in Croatia. The primary data source is the European Forest Fire Information System (EFFIS), which provides average weekly data on forest fire events and indices. The analysis in this study focuses on the annual distribution of the number of forest fires, revealing a distinct bimodal pattern. Interestingly, this bimodal distribution of fire events is not reflected in the corresponding annual distribution of the severity index, which suggests different factors impacting the number and intensity of fires throughout the year. Using machine learning techniques, including dendrogram analysis and k−means clustering, the study identified two statistically significant clusters in the data. The first cluster corresponds to a spike in the number of fire events in March. However, this increase in fire frequency is not accompanied by a corresponding rise in the severity index, suggesting that the fires are predominantly caused by human activities, such as agricultural burning, debris burning, or other forms of negligence, rather than by natural causes. The second cluster, characterized by a significant increase in the number of fires from mid−June to the end of September, coincides with the peak in the annual distribution of the severity index. This pattern suggests that fires occurring in this period are primarily driven by natural causes, such as prolonged droughts, high temperatures, and strong winds typical of the Mediterranean summer climate. Between these two clusters lies a relatively calm phase from April to early June. The phase can serve as a strategic operational pause, allowing fire management agencies to regroup and prepare for the critical fire season in the summer months. By understanding the temporal distribution and underlying causes of forest fires in Croatia, this study provides valuable insights and can help to devise more effective fire prevention and response strategies, ultimately contributing to the protection of the country’s valuable forest resources.
Key words: European Forest Fire Information System, forest fires, machine learning

Abstract: In this study, we present evidence using basal area increments (BAI) and ¹⁵N/¹⁴N nitrogen isotopic composition of Pinus sylvestris from sites near the industrial area in Dąbrowa Górnicza (Poland) to assess potential effects of pollution on tree growth and physiology. Changes in BAI reveal a marked long−term decline in stem growth during peak industrial pollution in the 1960s followed by a distinct subsequent increase after the mid 1980s. Coinciding with the earlier period of growth suppression, we also found a decrease in covariance of growth increments among trees and a weakening of the climatic signal in pine tree−ring chronologies followed by a change related to summer drought sensitivity since the 2000s. The ¹⁵N/¹⁴N ratios reveal distinct evidence of emissions from steel manufacturing since 1978 including a change in δ¹⁵N values from –10 to –4 ‰ in the polluted Scots pines. The results of this study show that there is a strong inverse correlation between tree−ring δ¹⁵N values and the nearby steelwork production rate coinciding with changes in growth rates and covariance among trees.
Key words: basal area increment, dendrochronology, industry pollution, nitrogen isotopes, Pinus sylvestri