Białowieża Forest

There are three large hotel complexes in and around Białowieża village on the Polish side (UNESCO and IUCN, 2008). Despite being relatively well-managed, this is a significant visitation pressure (Council of Europe, 2009). On the Belorussian side, the “Father Frost House”, situated in an exclave of the National Park, receives high numbers of visitors during the orthodox Christmas season. 275.000 tourists haven been reported for 2016 (State Party of Poland and Belarus, 2016), indicating stable tourism numbers around 300.000/annum (Kobyak, 2011), although the most recent periodic report for the Polish side states visitor numbers have been between 143,000 to 174,000 per annum over the past 4 years (State Party of Poland, 2024). Concerns were also previously expressed about, the new 190 km “bypass” road skirting Belovezhskaya Pushcha and improving access to the Belorussian part of the site from Brest, Hrodna and also Poland, may result in increased and potentially poorly managed tourism development (Karpik, 2011). However, the core areas of the site are under strict protection and are not directly affected by tourism development.

The threat from invasive alien species is gradually increasing as a direct result of human activities at the property, but also as an effect of climate change (State Party of Poland, 2025). There are close to 160 woody and close to 200 herbaceous plant species alien to Białowieża Forest (Adamowski et al., 2002), which are spontaneously spreading in the site's limits. The most wide spread are red oak (Quercus rubra), domestic apple (Malus domestica) ash-leaved maple (Acer negundo) and black cherry (Prunus serotina). These present significant threats to native plants and ecological processes, and thus require further monitoring (UNESCO and IUCN, 2008, Adamowski et al., 2002). Among non-woody invasive species the most widespread in forest ecosystems is Impatiens parviflora and in non-forest ecosystems (but encroaching on logged areas) Solidago canadensis/Solidago serotina/Solidago gigantea. Locally they dominate the landscape suppressing native vegetation, thus, negatively affecting native flora and fauna, especially invertebrates. Among the vertebrate animals Neovison vison and Nyctereutes procyonoides are widespread, affecting biodiversity of their prey and taking part in dispersal of non-native plants (e.g. Prunus cerasifera) (Kauhala and Kowalczyk, 2011; Brzeziński et al., 2019). Procyon lotor have also been observed, but only very limited number of times and it needs to be carefully monitored. There is strong concern about road construction and maintenance materials brought into the property without apparent screening for alien or invasive species (e.g. vascular and nonvascular plants, invertebrates, and fungi) (UNESCO/IUCN 2024). While not all alien species become invasive at the large landscape scale, the lack of screening of road materials (soil, aggregate, gravel, etc.) has raised strong concern about the full scope of invasive species that may have been introduced into the property. In Poland, forest districts participate in the project entitled: “Comprehensive project for the protection of species and natural habitats on areas managed by the State Forests”, financed within the framework of Infrastructure and Environment Programme funds and own funds in Poland. Within the project Impatiens parviflora and Reynoutria japonica are being removed. There were several joint activities taken to eradicate some of alien species, e.g. action of the
Białowieża Forest District and the Białowieża National Park to eradicate Impatiens parviflora in the immediate vicinity of the Białowieża National Park's strict reserve, or the action carried out by the Hajnówka Forest District to eradicate Solidago canadensis on the route of the narrow-gauge railway and the former timber depot near the Forest District. Other institutions and the local community were also involved. As part of the forest districts' hunting management, raccoon eradication is carried out on an ongoing basis (State Party of Poland, 2025).

A network of paved and unpaved roads exists within the World Heritage site, particularly on the Belarusian side, many of which are maintained in a 1km x 1 km grid patter for fire prevention purposes (UNESCO/IUCN 2024). During its evaluation of the site’s extension IUCN recommended that “the States Parties carefully assess the real need for maintaining these roads and fire prevention corridors, and reduce their numbers through a programme of rationalization, accompanied by appropriate monitoring” (IUCN, 2014). At the time of the 2018 UNESCO/IUCN Reactive Mission, a major upgrading of a 15,6 km forest road connecting the Białowieża and Narewka villages on the Polish Side was underway (UNESCO, 2019). The Narewkowska road was a dirt road open to the public and classified as a forest road and under the management of the State Forest System. As the road allowed for a shortening of travel times between the two villages, the SFS decided to upgrade it to a tarmac road. With pavement, and introduction of the road into popular car navigation systems (e.g. Google Map), it was expected that the number of cars passing through it would increase in volume, timing and speed, causing higher risks for crossing animals and reducing connectivity of the ecosystem separated by the road (UNESCO, 2019). The road crosses Forest Reserves (zone 2) and zone 3 areas as well as Nature 2000 sites and raised concerns about impacts including fragmentation, changes to the hydrology and road kills of wildlife. The upgraded Narewkowska Road was officially opened on 3 February 2020, and research showed that after the upgrade, traffic increased threefold, from an average of 29 cars to 91 cars with peaks of up to 351 cars a day (Chylarecki and Selva 2021). Car traffic also showed a clear seasonal and weekly pattern, with more cars using the road in summer months and on weekends. In 75% of the days the vehicle load of 46 cars per day projected in the EIA was exceeded. The study recorded 509 killed vertebrates within a 17 month period and calculated the annual mortality of vertebrates on the road to be 43 animals per km. 55 % of the killed animals were amphibians, 28% reptiles, 12% mammals and 8% birds. No accidents were recorded involving the most valuable species such as bison, wolf or lynx (Chylarecki and Selva 2021). Despite the 30 km/h speed limit for the Narewkowska Road, the average recorded speed was 52,4 km/h with 25% of cars exceeding 60 km/h (Chylarecki and Selva 2021). Also of increasing concern is the increased traffic timing and volume across, combined with increased maintenance of the entire paved and unpaved road network in the property as a result of the heightened activity by the military, the border guards and the police linked to the border security (UNESCO/IUCN 2024). The greatly increased use and maintenance of the entire road network is expected to be actively spreading invasive plant species across the property (UNESCO/IUCN 2024). The Polish State Party has recognized these issues and committed to implementing measures to reduce the traffic impacts, including putting in place additional measures (other than speed signs) to limit vehicle speed, fencing of the roadway to protect small mammals. and reconstruction of existing crossings under the roadway for amphibians and small mammals (UNESCO/IUCN 2024). In 2021, the Polish military was authorized to build a new service road through the property along the Poland-Belarus border. This road is approximately 0,5 m height and 8 m width and was constructed for use by heavy machinery in further border security infrastructure. On sandy soils, the construction of the road only required levelling but in humid and swampy areas, the roadbed was excavated, a geofabric was put in place followed by a gravel bed. Although the border barrier and service road were created inside the 15 m border strip situated in zone 4, in several areas trees were also cut in zone 1 and zone 2. In areas where small streams cross the service road, culverts were put in place, although the width and number of the culverts seem insufficient to cope with peak water flows (UNESCO/IUCN 2024).

In 2017, the European Commission referred Poland to the Court of Justice of the EU over serious concerns about widespread logging operations within the Polish part of the property and requested the Court for “interim measures compelling Poland to suspend the works immediately” (European Commission, 2017). An interim Decision by the Court of Justice issued on the 27th of July 2017 called on Poland to halt logging, recognizing high potential for serious and irreversible damage to Białowieża Forest. Subsequently, the Court of Justice of the European Union sentenced that increased logging was illegal, mainly due to procedural problems (Court of Justice, 2018). Logging negatively affected the partially protected zone II, which includes old-growth forest and where no active forest management is to be allowed. These activities have disrupted the ecological and natural processes in the World Heritage site, resulting in negative impacts on its Outstanding Universal Value (IUCN and UNESCO, 2018; UNESCO, 2019). Since the Court decision, widespread logging ceased on the State Forests and trees are currently felled only in limited areas along the public roads and fire safety. However, the military has also removed a 15 meter wide swath of trees across all age classes along the entire Poland-Belarus border within the property (UNESCO/IUCN 2024) for purposes of border security measures. In Belarus, measures related to clearing forest roads and glades across an area of nearly 50,000 hectares have been excluded from the draft forest management plan. To preserve habitat mosaic, 12,000 hectares of non-forested areas have been excluded from artificial reforestation plans (State Party of Belarus, 2025).

In general, global climate change is expected to result in subtle, major, and abrupt state-transition changes in natural ecosystem structure and functions (IPCC 2023). Old-growth forests like the property can be expected to absorb short-duration extremes in the regional climate regime (e.g. summer drought, dry winter) without fundamental changes in forest structure and ecological processes. Longer term changes in seasonal timing and amount of precipitations leading towards overall drying of the property have potential to result in outsized changes in forest health and composition, including changes in light penetration at ground level, understory herbaceous dynamics, understory animal biodiversity, soil genesis, seasonal soil moisture profiles, seasonal water runoff dynamics, wildfire risk, and altered fungal communities and decomposition rates (IPCC 2023). The hydrologic conditions of the forest are also responding to climate change dynamics, including increasingly warm winters, limited amounts and duration of snow and ice, leading to reduced surface and subsurface water retention (UNESCO/IUCN 2024). Recent analysis of hydrologic data from the Białowieża Forest indicate a slight decrease in the average annual river flows, with decreasing spring flood runoff and an increase in winter runoff in natural watercourses (Hedjuk et al. 2021; Volchak et al. 2022). Indeed, the groundwater table in the Polish part is estimated to have declined by approximately 0.4m (Pierzgalski et al. 2002). The new Polish border service road and the the new Polish border barrier wall now serve as a compacted earthen dam that blocks year-long and seasonal transboundary hydrology flows, creating new areas of waterlogged/flooded soils on the Belarusian side, and drying soils in the Polish side adjacent to the service road/barrier wall (UNESCO/IUCN 2024). In addition to the drying of the forest as a result of climate change, many parts of the forest have been drained in the past and some rivers were channelized. In addition, wetland areas adjacent to the property were drained for conversion into agricultural land, especially on the Belarus side resulting on unnaturally dryer environmental conditions across the property. The deterioration of the hydrology and drying of the property has been observed for years, and Poland and Belarus are independently undertaking management actions in the property to restore the natural hydrology (UNESCO/IUCN 2024). In the Belarussian part, hydrologic restoration includes removing drainage infrastructure and construction of earthen dam structures to reduce surface flow rates and increase adjacent subsurface water table levels in areas that were extensively channelized and drained tables (UNESCO/IUCN 2024). Beavers are beginning to occupy areas where hydrological restoration activities are underway. Interestingly, restoration of natural hydrology in Belarus has opened an ecological niche for beavers that are likewise contributing to reduced surface flow rates and have become prey for wolves that exhibit seasonal prey switching between red deer and beaver. The recent mission notes that in the past, these activities had been supported by donor funding and welcomes the fact that efforts are being continued in spite of the interruption of this external funding (UNESCO/IUCN 2024). In Poland the Bureau of Forest Management and Geodesy prepared a detailed inventory of all watercourses (permanent and seasonal) in the Białowieża forest catchment area (UNESCO/IUCN 2024), and 50 small dam structures of natural materials have been installed in management zone 4 of the property to reduce surface flow rates of small seasonal streams and raise adjacent water tables. However, there remain many drainage ditches in the property along the boundaries of forest plots and roads that could be blocked to further increase water retention in the property. Further hydrological restoration works in the polish part of Białowieża Forest would benefit from one overarching strategy outlining priorities and approaches for hydrological restoration.

Within the Belarus part of the property, a physical border barrier called “Sistema” is situated close to the international border and has existed since the early 1980s. This structure follows the international border at varying distances (up to 2,5 km from the border) and is composed of a fire break, a parallel dirt road for service vehicles with a total width of about 15 meters, and a parallel electrified barbed wire fence with a height of about 2,5 meters and electronic movement detection cables. The issue of ecological connectivity linked to the presence of the “Sistema” was raised by the 2014 IUCN evaluation of the nominated extension of the property, which noted that this barrier prevents exchanges of large mammals, in particular bison, between the Polish and Belarus part of the property. At the same time, the IUCN evaluation noted the ongoing scientific debate concerning the potential benefit of separating the Poland and Belarus bison population for the management of genetic diversity. Nevertheless, IUCN recommended that the two States Parties monitor the impacts of the border fence and consider the options to improve connectivity within the property, and to facilitate wildlife movement. This was also reflected in the 2014 inscription Decision of the Committee (38 COM 8B.12), which requested to expedite the preparation and adoption of a Transboundary Management Plan for the property addressing all key issues concerning the effective conservation and management of this transboundary property, including the need to increase functional ecological connectivity in the property. The issue of ecological connectivity was raised again by the 2018 UNESCO/IUCN Reactive Monitoring Mission noting that while there was evidence that wolf and lynx moving between the Belarus and Polish components of the property in spite of the “Sistema” barrier, there remained a critical need to undertake new discussions on how to improve connectivity in the overall Białowieża forest ecosystem, including across the state border between Belarus and Poland. In 2021, illegal migration increased exponentially along the so-called “Eastern Borders Route”, the 6000 km land border between Belarus, Moldova, Ukraine, the Russian Federation and the eastern EU Member States - Estonia, Finland, Hungary, Latvia, Lithuania, Norway, Poland, Slovakia and Romania. According to Frontex, the European Border and Coast Guard Agency, a record 8,184 illegal border-crossings were detected in 2021 along this eastern border, a more than tenfold increase in comparison to 2020 (Frontex 2024). According to information provided by the State Party, Poland was directly affected by this steep increase of illegal migration, and in 2021 recorded a total of 39,664 attempts to illegally cross the Poland / Belarus State border, compared to 129 in 2020 (Poland Ministry of Climate and Environment 2022). In response to this increased illegal migration, the Government of Poland decided first to erect a makeshift barrier made of concertina razor wire on the international border with Belarus, including the 55,9 km of the border situated in the property. On 29 October 2021, the Polish Parliament adopted the “Act on the construction of state border protection”, establishing the legal basis for constructing a border barrier. On 10 January 2022, the World Heritage Centre received a letter from the State Party of Poland, confirming plans to construct a permanent physical border barrier along the entire international border with Belarus including in the property. Works on the main border barrier started in January 2022 and were completed in June 2022. The Polish border barrier was erected along the international border in the property, approximately 1 m into the Polish territory (to allow for a 1 m band to facilitate the construction works). A 15 m strip along the international border in Poland is included in the active forest management zone (zone 4), given its legal status as a border zone. This border strip in Poland is immediately adjacent to the strictly protected zone of the BNP (zone 1), the partially protected zone of the BNP and several forest reserves (zone 2) and areas included in the partial protected zone II (zone 3). On the Belarus side, almost all areas directly adjacent to the international border are within the strictly protected zone. Hence the border strip and the barrier cross the most pristine and ecologically valuable areas of the property. The newly constructed border barrier consists of 5 m steel posts with a 0.5 m foundation, topped with a 0.5 m concertina wire. Every 5 meters, two small holes are provided in the concrete base of the barrier, supposedly to allow for the movement of small animals. In addition, there are three larger gates foreseen with a width of 5 m and a height of 4.5 m, which in theory could be opened to facilitate movements of larger animals. However, to date, these passages remain permanently closed. In addition, there are smaller “technical gates” at regular intervals, to allow for maintenance work. The barrier is completed with electronic surveillance equipment, including motion sensors and cameras (UNESCO/IUCN 2024). To construct the barrier, an 8 m service road of approximately 0,5 m height and 8 m width was constructed allowing heavy machinery to put in place the panels. On sandy soils, the construction of the road only required levelling but in humid and swampy areas, the roadbed was excavated, a geofabric was put in place followed by a gravel bed. Although the border barrier and service road were created inside the 15 m border strip situated in zone 4, in several areas trees were also cut in zone 1 and zone 2. In areas where small streams cross the service road, culverts were put in place, although the width and number of the culverts seem insufficient to cope with peak water flows. No culverts were foreseen on the smaller water courses. In October 2023, the main barrier was complemented by a second barrier made of concertina wire on the edge of the service road. This second barrier was protected with so-called woven-wire forest netting on the side facing the forest, to avoid animals getting entangled in the concertina wire. The objective of the second barrier is to slow down illegal migrants who were able to cross the main border barrier in order to allow more time for the Border Guard to apprehend the trespassers before they vanished into the adjacent forest. The woven wire fence appears to be successful at preventing wildlife entanglement, yet the consequence of that success is that mid- and large-body sized wildlife cannot move west to east across the closely layered woven wire/concertina fences. The border barrier structure is absent from the section of the border formed by Leśna and Podcerkówka rivers; however, in this section a double barrier of concertina wire was put in place, which is protected by woven-wire forest netting on the side facing Poland, but not on the side facing Belarus, creating risks of entanglement for animals trying to cross from the Belarus side. The service road is currently used as a patrol road, to allow for rapid movement of Border Guard and Army staff. Makeshift guard post shelters are situated every few 100 meters with removable toilet facilities and wood stoves. The service road is constantly patrolled on a 24-hour basis by Polish Border Guard and Army personnel on foot and in vehicles, resulting in constant movement and noise. There has been discussion by the Polish Border Guard to add additional surveillance cameras facing Belarus to allow for early detection of approaching migrants as well as the installation of cross beams to the metal poles to strengthen it. Further potential development of the barrier is also being considered by the Ministry of the Interior and Administration, including tarmacking of the service road, the erection of watch towers at regular intervals, the installation or permanent lighting to illuminate the border strip at night and having continuous surveillance by drones. As the “Sistema” is situated up to 2,5 km away from the international border in certain areas, the erection of the border barrier in Poland also created several larger areas that are currently “squeezed” between the two State Party barriers, including bison, that are trapped in these areas between the two State Party border barriers. These areas are almost exclusively situated in the strict protection zone (3947 ha in zone 1) (UNESCO/IUCN 2024). The border area in the property is now characterized by a succession of nine parallel infrastructure layers that are impeding wildlife movements (e.g. Poland: woven-wire forest netting, a barrier of concertina wire, an 8 m service road, the actual border barrier wall and a 1 m construction strip where vegetation was removed; Belarus: a service road, a ploughed fire strip, an electrified barbed wire fence and a second ploughed area. In spite of the construction of the border barrier and the constant patrolling by the Polish Army and Border Guard, the pressure of illegal migrants is reported to remain high. Increasingly, illegal migration continues along the full Poland-Belarus border, though migration is now mainly concentrated in the border area situated in the property (UNESCO/IUCN 2024). According to the figures provided by the Polish Border Guard, 87% of all attempted illegal border crossings on the Belarus / Polish border in 2024 took place inside the property, showing that the border area in the property has become the focus area of migration (UNESCO/IUCN 2024). According to figures quoted in the press and by NGOs, from January 1 to September 17 there were 17,488 "prevented border crossings". However, data from migrants arriving in Germany indicate that in the same period 12,971 were able to cross the border barrier into Poland without being apprehended and arrive in Germany. Following upon the decision by Poland to construct a physical border barrier, the World Heritage Centre reminded Poland of the need to carry out an impact assessment (EIA) as foreseen in the Operational Guidelines. The October 2021 Polish Act on the Construction of State Border Protection Installations stated that that existing regulations, including those relating to construction law, water law and environmental protection law, as well as the regulations on the provision of environmental information and the regulations on the protection of farmland and forestland as well as environmental land, did not apply to the border barrier construction project. This means that the Act made it possible for the construction to go ahead without the normal legal provisions, including the preparation of an EIA. In May 2023, the State Party of Poland submitted a document entitled “Analysis of the impact of the construction of the barrier on the subjects of protection of the Natura 2000 site Białowieża Forest together with the BNP”. The IUCN review of this document noted that this analysis failed to consider the property as a whole, including important attributes of its OUV and integrity, such as connectivity and habitat fragmentation, and only considered direct impacts on the Natura 2000 sites included in the Polish part of the property. It also did not assess the impacts of different options for the project, including the “no project option”. It cannot therefore be considered as an EIA in line with the Guidance and Toolkit for Impact Assessments in a World Heritage Context. In September 2023, the World Heritage Centre received an additional document entitled “Assessment of the impact of the barrier on the border between Poland and Belarus on the UNESCO World Heritage Site Białowieża Forest” that included an analysis of the impacts of the border barrier on the OUV of the property, as well as an analysis of so-called variants, including a “zero variant”. The IUCN review of this September 2023 document notes a number of limitations to the assessment, including a lack of clarity on the methodology used to assess the impacts on the attributes of criteria (ix) and (x), the lack of analysis on the potential negative impacts of the barrier on bison, the lack of consideration of the additional and cumulative impacts of the new barrier in addition to the Belarus “Sistema” on wolf and lynx, the fact that only the impacts of the barrier on the integrity of the Polish component of the property are considered and not the transboundary property as a whole, and the lack of full and effective participation of all relevant rights holders and stakeholders. The 2024 State of Conservation report by the State Party of Poland confirmed that the barrier constitutes an obstacle to the dispersion of medium-sized and large terrestrial animals and acknowledges that there is no evidence indicating that the technical solutions applied to act as animal crossings are effective in ensuring free migration of wild animals (State Party of Poland, 2024). From the above, it can therefore be concluded that no proper assessment of impacts of the border infrastructure put in place by Poland on the OUV of the property were conducted prior to its construction, as is required under the Operational Guidelines. While the Belarus “Sistema” barrier historically maintained desirable separation of two 20th century captive breeding lines (e.g. Poland: lowland B. b. bonasus and Belarus: lowland-Caucasian cross of B. b. bonasus and B. b. caucasicus), this separation is no longer relevant as recent genetic analyses have confirmed little genetic differentiation between these two subpopulations (Machova et al. 2022, Olech et al. 2023). This means that from an ecological point of view, it would be desirable to restore the connectivity for bison across the entire property. While both of the respective sub-populations of the property now exceed minimum viable sub-population size (e.g.> 150 adults) and exhibit reasonably good reproductive fitness and exhibit relatively uniform genetics (Machova et al. 2022); they are now completely segregated for the foreseeable future, with no opportunity for any meaningful demographic or genetic exchange through transboundary movement, due to an array of historic and recent border control infrastructure that includes spatially layered electrified barbed wire, concertina wire, woven wire, and steel barriers. As with bison above, respective red deer (Cervus elaphus) and elk (Alces alces) subpopulations are also now completely separated for the foreseeable future, with no opportunity for any meaningful demographic or genetic exchange through transboundary movement due to border control infrastructure. Although the lynx as a species is not at risk of extinction across Europe, there is low genetic diversity and kitten survival for lynx in the property (Kowlacyzk et al. 2015, Mattison et al. 2022). In addition to the physical barriers described above for bison and red deer, there are also conflated disturbance zones on both sides of the border arising from 24-hour border security activities (e.g. noise, human and vehicle movement, smell, light, etc.) that are expected to now serve collectively as an impervious barrier to transboundary lynx movements. Presently, there are approximately 9 adult lynx in the Polish part of the property that likely include only 2 adult females exhibiting increased intra-specific competition (personal communication, R. Kowalcyzk, Mammar Research Institute, Polish Academy of Science). As the only source for lynx to move into the Polish part of the property is from Belarus, there is increasing likelihood that if lynx reproduction in the Polish part collapses, local extinction could occur there within 5-10 years (personal communication, R. Kowalcyzk, Mammar Research Institute, Polish Academy of Science). There are 58 - 76 wolves living across the full property, 35 - 48 in Poland, 23-28 in Belarus ((personal communication, R. Kowalcyzk, Mammar Research Institute, Polish Academy of Science). As described for lynx, individual wolves also were shown to be able to occasionally cross the “Sistema” when it was the only border barrier, and now the conflated physical barriers and disturbance zones on both sides of the border within and adjacent to the property are expected to limit or prevent wolf transboundary movements (Smith et al. 2022). The wolf is not only a flagship species, which contributes to criterion (x), the SOUV also explicitly mentions the importance of mammalian predators (e.g. wolf, lynx and otter) and their role in supporting complete food webs as a justification for criterion (ix). The Eurasian brown bear was hunted to extinction in Białowieża in the 19th century, yet bears have again been sighted in the property, apparently moving from other regions in Belarus (UNESCO 2024). Recent sightings of brown bear cubs in Belarus indicate the species might be able to successfully re-establish itself in the Belarusian side of the property. Before the erection of the Polish border barrier, sightings in Poland indicated the species was also able to cross the “Sistema”. However, with the Polish border barrier in place, it seems now unlikely that the species will be able to re-establish itself in the Polish part of the property. In addition to the focal species discussed above, the property supports a robust wildlife species diversity (54 mammal, >250 bird, 13 amphibian, 7 reptile, and ~12,000 invertebrates) (Gutowski and Jaroszewicz 2001). The combined historic and recent physical barriers described above, conflated with disturbance zones on both sides of the border arising from aforementioned 24-hour border security activities, are expected collectively to function as a non-porous barrier to landscape scale movement by small and mid-sized terrestrial vertebrates, but not for birds or flying invertebrates. At present, there is no indication that the physical barriers and disturbance zones described above will negatively impact subpopulation viability for small and mid-sized terrestrial vertebrates, birds or flying invertebrates. Of note, there may be emerging “edge effect” of border security noise and light on localized nocturnal species movement and feeding ecology, especially with further upgrades to the barrier which are currently under discussion, such as the installation of permanent lighting to illuminate the border strip at night and having permanent surveillance by drones (UNESCO 2024). As described above, the new Polish barrier wall includes not only a below- and above-ground concrete foundation, but also includes an adjacent service road of approximately 0,5 m height and 8 m width that was constructed to support heavy machinery used to place the concrete foundation panels. On sandy soils, the construction of the service road only required levelling but in humid and swampy areas, the roadbed was excavated, a geofabric was put in place followed by a gravel bed. Thus, the Polish service road now serves as a compacted earthen dam that blocks year-long and seasonal transboundary hydrology flows, creating new areas of waterlogged/flooded soils on the Belarusian side, and drying soils in the Polish side adjacent to the service road/barrier wall. The mission was advised that approximately 200 ha in the Belarusian side adjacent to the Polish barrier wall/service road have become flooded with standing water up to 0.5-0.7 m depth that cannot drain away, with an additional 800 ha of waterlogged soils that could in the near term also become flooded with standing water.

In addition to the physical border barriers described above, there are also conflated disturbance zones on both sides of the border arising from 24-hour border security activities (e.g. noise, human and vehicle movement, smell, light, etc.) that are expected to collectively reduce habitat suitability for wildlife across taxa within and adjacent to the border management zone, and also serve as an impervious barrier to transboundary movements by mid- and large-body size wildlife. With east to west illegal human migration continuing despite the combined respective Polish and Belarusian border security infrastructure; the mission was informed that there are also acute, distributed and cumulative illegal migrant effects across the most highly protected areas of the property, including collecting down wood for warming fires, fire effects on soils inside fire pits, fire spread outside of fire pits, trash and debris, abandoned medicines, water pollution, human faeces and urine, and disturbance of soil surface and wildlife. It can therefore be concluded that the disturbance created by the Polish border barrier and the increased activity in the border area and in the Polish part of the property in general will have a significant impact on wildlife in the property (UNESCO/IUCN 2024). In addition to the array of direct and indirect impacts of the border security infrastructure and operations that conflate with disturbance and edge effects on wildlife and hydrology described above, there are also concerns about potential cascading consequences from infrastructure construction and continuing maintenance. Foremost is concern about road construction and maintenance materials brought into the property without apparent screening for alien or invasive species (e.g. vascular and nonvascular plants, invertebrates, and fungi). While not all alien species become invasive at the large landscape scale, the lack of screening of road materials (soil, aggregate, gravel, etc.) has raised a strong concern about the full scope of invasive species that may have been introduced into the property. It was unclear to the mission whether materials expected to be used for maintenance of both the Polish and Belarusian border service roads are being sufficiently screened for alien or invasive species. Culverts and gates were included into the Polish border barrier infrastructure as mitigations to address local hydrology and wildlife movements. Several larger culverts were placed under the Polish steel barrier wall and adjacent service road at locations where sub irrigated and surface stream flows from Belarus to Poland were known to occur. These few larger culverts do not appear to allow sufficient flows during peak periods and become choked with debris, causing east-to-west water flows to backup in the Belarus side, and causing some erosion under the service road. The regularly spaced small culverts built into the barrier wall foundation do not appear to support any meaningful groundwater movement or small wildlife movement. Indeed, it does not appear that the small culverts provide any meaningful mitigation function. Natural hydrologic flows are being disrupted, and there are several areas where water has “backed-up” in Belarus causing local flooding of 0.5-0.7 m deep. The Polish border barrier rests on a concrete foundation wall set ~1m below ground level and ~0.5 m above ground that appears to block all ground-surface level movements by invertebrates or small vertebrates. The steel barrier wall itself is impenetrable by design for humans, yet also has the same consequence for mid- and large-body sized wildlife. Large and mid-sized hinged gates built into the Polish barrier wall were designed to be opened to support wildlife movements, though they have ever been opened for such purpose. However, even if they would be opened, researchers from Poland and Belarus pointed out that the gates have not been placed on animal movement routes and are too small to allow for meaningful movement of wildlife (UNESCO/IUCN 2024). In summary, the layered Polish border security infrastructure combined with the Belarusian “Sistema'' are now functioning as an essentially impenetrable barrier to wildlife movement (other than birds and flying insects) affecting the integrity of the property (UNESCO/IUCN 2024). The Polish border barrier and its foundation are disrupting local sub irrigated and surface hydrology leading to degradation of local forest stand health and condition on both sides of the barrier wall (e.g. flooding in Belarus, de-watering in Poland). The construction and maintenance of the Polish border security infrastructure appears to be exacerbating the establishment and spread of alien and invasive species, and it is not clear whether Poland or Belarus are now screening construction and maintenance materials for alien and invasive species, or indeed have any plans to actively address the establishment and suppress the spread of such species arising from border security activities. In addition to acute local site impacts by border security infrastructure and activities described above, there are also “edge effects” across the property at variable distances away from the border. Human noise and light pollution are very likely to disrupt diurnal and nocturnal wildlife behaviour and movement patterns. For example, the combined 24 hour per day human presence and movement, noise and light in the immediate border zone, and the wildlife disturbance “edge effect” spreading out from the border zone, are likely contributing to reduced habitat suitability for, and heightened competition between, the remaining two adult female lynx in the Polish side; thus increasing the potential for local extinction of lynx in the Polish part of the property (UNESCO/IUCN 2024).

Many journalists and European institutions (see e.g. Europol, 2022) reported since 2021 that Belarus and Russia actively support trafficking people on the move from Africa and Asia to the Poland's border, including Białowieża Forest property. During the UNESCO/IUCN reactive mission 2024 Polish Border Guards reported that most of illegal crossings along the Poland/Belarus border took place in the limits of the property, which suggests that the property is used by criminal networks as a place to move people across the border. Trafficking people to the border in the limits of the property causes an increase in the number of unauthorized people (and uniformed services) disturbing ecosystems of the Białowieża Forest on the Belarussian site and causes damages on the Polish site associated with the measures taken by Poland to protect the border (border infrastructure, vehicle traffic, high number of military and border guard servicemen).