The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, Russia

219 ACTA ZOOLOGICA BULGARICA Applied Zoology Research Article Acta Zool. Bulg., June 2025, 77 (2): 219-230 Published online 10 March 2025 DOI: https://doi.org/10.71424/azb77.2.002856 https://www.acta-zoologica-bulgarica.eu/2025/002856 The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, Russia Egor L. Lykov Information and Analytical Centre for Protected Areas Support; 3 Malaya Gruzinskaya Str., Moscow 123242, Russian Federation, E-mail: [email protected] Academic Editor: Mihaela Ilieva Abstract: The common wood pigeon has successfully colonised urban habitats in Europe over the past two centuries and this process continues to this day. The aim was to assess the state of the urban population of the species in Belgorod (Russia) during the breeding season. The majority of the research was conducted in June 2021 and May 2022. The average population density of the common wood pigeon in the city was 1.7 ± 1.2 pairs/10 ha, while the highest population density was observed in the recreational parks (2.8 ± 1.6 pairs/10 ha). The species started to utilise urbanised habitats for breeding around the 1990s, including the green residential areas with predominantly five-story housing blocks, where the current population density was 1.2 ± 0.3 pairs/10 ha. In general, the average population density of the common wood pigeon in Belgorod was significantly lower than that in other European urban areas. In the green residential areas with predominantly five-story housing blocks, nests were located on trees belonging to eight taxa. Nests were most often placed in linden (25.9% of the total number of nests found), birch (14.8%) and horse chestnut (14.8%). The height of nests above the ground varied from 7 to 16 m, averaging 11.1 ± 0.49 m. The data obtained indicated an urban population of the species having formed in the city and being at one of the final stages of synanthropisation. Key words: breeding, city birds, Columba palumbus, population density, synanthropisation Introduction Urban areas represent the extreme of the humanmodified environment, at the same time containing preserved fragments of original habitats (Jokimäki & Suhonen 1993, Fey et al. 2015, Varga & Juhász, 2020). Some bird species have been able to colonise urban habitats and form urban populations there, which differ from natural populations in a number of features, including higher breeding density, a longer breeding season, reduced migratory activity and tolerance to humans (Vuorisalo 2010, Lykov 2015, 2021a, b, Friedman & Suslov, 2022). Birds are attracted to the urban environment due to the greater availability of food sources, the presence of convenient nesting sites, including human structures, and a warmer microclimate. However, the city is an ecological trap for birds (e.g., birds die on glass structures) and the number of predators in some places in the city can reach high values (Jokimäki et al. 2005, Lykov 2009a, Csathó & Bozó 2022, Friedman & Suslov 2022). Originally belonging to the forest avifauna, the common wood pigeon (Columba palumbus) is 220 Lykov E. L. one of the bird species that has successfully colonised urban habitats in Western and Central Europe (Tomiałojć 1976, Hewlett 2002, Šťastny et al. 2005, Veiserbs & Jacob 2005, Witt 2005, Lykov 2009a) and to a lesser extent in Northern, Eastern and Southern Europe (Tomiałojć 1976, Murgui 2005, Bobenko 2009, Bea et al. 2011, Fey et al. 2015, Sakhvon & Kövér 2020, Malovichko et al. 2021), as well as in Asia (Karpov & Berezovikov 1994, Mitropolsky 2008, Gashek & Popov 2022), over the past two centuries. The process of active colonisation by the common wood pigeon continues to this day in some cities and smaller settlements (Sakhvon & Kövér 2020, Malovichko et al. 2021, Csathó & Bozó 2022, Gashek & Popov 2022, Lykov & Sviridov 2024). The species colonise urban habitats due to the availability of convenient nesting sites in the form of trees suitable for breeding and accessible and constant food sources (Vuorisalo 2010, Juhász & Varga 2019, Luna et al. 2024), while birds also fly to feed in nearby agricultural fields, the presence of which near the city favours breeding of the species (Tomiałojć 1976, Jędro et al. 2008, Bendjoudi et al. 2015). In addition, hunting is not carried out in settlements, which protects the birds (Csathó & Bozó 2022). However, over the past decades, the number of aerial predators, mainly the hooded сrow (Corvus cornix), has increased significantly in cities, due to which the breeding success of the common wood pigeon has significantly decreased (Tomiałojć 1979, 2005, 2021). Urban populations of the species have emerged, among others, in some Russian urban areas, where such populations are at different stages of formation (Bobenko 2009, Lykov 2009a, Astafieva & Grishanov 2012, Malovichko et al. 2021, Gashek & Popov 2022) and the city of Belgorod is no exception. Until the present study, no special studies of the common wood pigeon population in Belgorod have been conducted. The exact time of the emergence of the urban population of the species in Belgorod has not been identified. According to N.Yu. Belov (unpublished data), the common wood pigeon urban population in Belgorod has existed at least since 1993, when he began observing birds in the city. He noticed occasional inhabited nests located in willows (Salix spp.) in 1993 in the city centre in Pobedy Park, on the old territory of the zoo, which had an area of 3.4 ha. Thus, the birds bred in the central part of the city as early as the early 1990s and most likely, the urban population began to form in Belgorod in the 1980s. The aim of this paper was to assess the state of the urban population of the common wood pigeon in Belgorod during the breeding season. Materials and Methods Research area The field research was carried out within the administrative boundaries of Belgorod as part of a program to study model bird species in Russian urban areas. Belgorod (50°35’ N, 36°35’ E) is the administrative center of the Belgorod Region, Russia, located 695 km south of Moscow, on the southern edge of the Central Russian Upland, on the right bank of the Seversky Donets River (Investment passport of the City of Belgorod urban district 2024) in the chernozem belt in the forest-steppe zone (Belgorod reference site 2022). The population of the city was 391.3 thousand people as of January 1st, 2022 (Federal State Statistics Service Regional Office of the Belgorod Region 2024a), while the area of the city was 153.1 km2. The urban area and its surroundings lie on an undulating plain, heavily indented by gullies and ravines (Supporting Materials for the General Plan for the Development of the City of Belgorod Urban District until 2025 2019). The forest cover of the area around the city is about 9%. Isolated groves, mostly oak (Quercus robur), occasionally pine (Pinus spp.) and linden (Tilia spp.), are scattered among the agricultural lands formed in place of meadow steppes and steppe meadows. Oak woodlands are the most typical, being located on the interfluvial plateau between the Seversky Donets and Koren Rivers, on the upper sections of river valley slopes, on ravine and gully slopes and sometimes on elevated parts of floodplain terraces. Upland oak forests extend as narrow (1–3 km wide) strips along the elevated right bank of the Seversky Donets River. In other areas, remnants of once extensive oak forests are scattered along ravines and gullies as small patches of low oak woodland and shrubland. Pure oak stands are very rare. The forests usually have a multi-layered structure involving various tree species: ash (Fraxinus excelsior), elm (Ulmus spp.), maple (Acer spp.), with the lower layers composed of bird cherry (Prunus padus), rowan (Sorbus aucuparia), wild apple (Malus spp.) and pear (Pyrus spp.). Birch (Betula spp.) and aspen (Populus tremula) forests are also widespread, being indigenous communities confined to small depressions on watersheds and to northern slopes with chalk subsoil (Supporting Materials for the General Plan for the Development of the City of Belgorod Urban District until 2025 2019). The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, 221 Green spaces in Belgorod occupy a total area of 4888.9 ha as of 2021 (Belgorod 2021. City Guide in Numbers 2022), being distributed rather evenly throughout the city. Parks constitute about 60% of the area of public green spaces. The presence of forests within the city limits (urban forests) on an area of 1,353 ha (Supporting Materials for the General Plan for the Development of the City of Belgorod Urban District until 2025 2019) should be viewed as a positive factor. Data collection Six main habitats were examined: the forest park, recreational parks, cemeteries, small-house areas, squares and boulevards and green residential areas with predominantly five-story housing blocks. Censuses of breeding pairs of the common wood pigeon were carried out on designated census plots using the method of breeding territories mapping on June 12th–13th, 2021 and May 28th–29th, 2022. The census activities were carried out during daylight, including the morning and evening hours when the birds are most active. A total of 20 census plots with a total area of 271.7 ha were allocated (Fig. 1). The number of breeding pairs on each census plot was determined by the number of territorial birds, singing males and nests found. Each census plot was surveyed once (in 2021 or 2022). Data from the two years were combined for further analysis. The presence of two or more uninhabited nests on one census plot with no occupied nests found was interpreted as one pair. As a result, the average population density of the species was determined for each habitat and for the city as a whole. The surface area of the census sites, as well as the total area of parks and green residential areas with predominantly five-story housing blocks in the city were calculated using satellite maps in the Google Earth Pro application (version 7.3.6). The shares of the examined areas (Table 1) in the total surface area values of the habitats identified, with the exception of the green residential areas with predominantly five-story housing blocks, were calculated using the Supporting Materials for the General Plan for the Development of the City of Belgorod Urban District until 2025 (2019). A complete census of nests of the hooded crow and magpie (Pica pica) was carried out during the leafless period on April 20th–22nd, 2020 on plots in the small-house areas and green residential areas with predominantly five-story housing blocks, thus making it possible to assess the impact Fig. 1. Placement of census plots in Belgorod. The numbers of the census plots correspond to the numbering given in Table 1. Table 1. Percentage of the examined area for different habitats in Belgorod. №Habitat Total habitat area, ha Examined area, ha Examined area percentage, % 1. Forest park 119.0 44.7 37.6 2. Recreational park 112.4 73.9 65.7 3. Cemetery 120.0 29.3 24.4 4. Small-house areas 1720.0 54.0 3.1 5. Squares and boulevards 54.4 4.9 9.0 6. Green residential areas with predominantly five-story housing blocks 220.4 64.9 29.4 222 Lykov E. L. of these corvid species on the urban population of the common wood pigeon in Belgorod. The census of hooded crow and magpie nests was carried out on four census plots with a total area of 93.5 ha in the small-house areas and on four census plots with a total area of 107.2 ha in the green residential areas with predominantly five-story housing blocks, with simultaneous observation of the common wood pigeon on the same census plots. A targeted search for nests of the common wood pigeon was carried out only in the green residential areas with predominantly five-story housing blocks during censuses of the breeding pairs of the species, as well as during the complete census of corvid nests in April 2020. Each common wood pigeon nest found, occupied or unoccupied, was plotted on the map with an indication of its location and height above the ground. The colonisation of the Belgorod urban areas by the common wood pigeon was assessed using five stages of synanthropisation, as proposed by Tomiałojć (1976): Stage 0. Breeding in forests and groves away from populated areas; Stage 1. Breeding of individual pairs in urban forests, as well as in peripheral parks on the outskirts of cities or smaller settlements; Stage 2. Breeding in urban parks with a higher density than in natural habitats; Stage 3. Breeding in urban parks with a high density, as well as regular breeding in residential areas (on the streets); Stage 4. Breeding in urban parks with a high density, as well as breeding on the streets, including the downtown, cases of breeding on man-made structures. Regarding the population density and nest height of the common wood pigeon, the mean and standard error of the mean (M ± SE) were calculated. The population densities of the species in different habitats were compared using the Kruskal–Wallis non-parametric test. STATISTICA 6.0 (StatSoft, 2001) software was used for statistical evaluation of the obtained data. Results Population density The common wood pigeon was registered in Belgorod during the breeding season in all studied habitats, except the small-house areas. The average population density of the species in the city was 1.7 ± 1.2 pairs/10 ha, while the highest population density was observed in the recreational parks (2.8 ± 1.6 pairs/10 ha), with the species recorded in all seven parks, where the censuses were performed. In the small Kotofey Park, with an area of 3.1 ha, the population density reached 12.9 pairs/10 ha. The squares and boulevards were less preferred breeding habitats. The species was recorded in only one of the four squares and boulevards examined. The most urbanised habitat, the green residential areas with predominantly five-story housing blocks, had an average population density of 1.2 ± 0.3 pairs/10 ha (Table 2). The statistical analysis was conducted comparing the values of the population density in three habitats (recreational parks, squares and boulevards, green residential areas) using the Kruskal-Wallis test. The analysis demonstrated the absence of statistical differences (H=3.01; d.f.=2; p=0.222) between the habitats. In general, the average population density of the common wood pigeon in Belgorod is in most cases significantly lower than in other European cities and towns (Table 3). According to the literature data at our disposal, the maximum population density of 152.8 pairs/10 ha was recorded in Central Park in Legnica (Poland) in 2003 (Tomiałojć 2007), which is 90 times higher than the average population density recorded in Belgorod. Nest placement In the residential areas of Belgorod with predominantly five-story housing blocks, a total of 27 nests were found, which were built in trees belonging to eight taxa. Most nests were located in linden (25.9% of the total number of nests found), birch (14.8%) and horse chestnut (Aesculus hippocastanum; 14.8%; Table 4). Only broadleaf trees were used for nesting. The nest placement height in Belgorod varied from 7 to 16 m, with an average of 11.1 ± 0.49 m. A common wood pigeon nest found in the park between the Vezelka River, Vatutina Avenue, Pobedy Street and Popova Street was located in an ornamental Norway maple (Acer platanoides) with a spherical crown at a height of only 2.5 m. Assessment of the impact of major nest predators Both the hooded crow and the magpie breed in Belgorod. However, the hooded crow was a very rare species in the city with a population density of 0.2 pairs/10 ha in the green residential areas with predominantly five-story housing blocks and no nests found on the census plots in the small-house areas. The magpie was a much more common species than The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, 223 Table 2. Population density of the woodpigeon (Columba palumbus L.) on census plots in Belgorod in 2021-2022. №Habitat Census plot location Census plot surface area, ha Number of pairs Population density, pairs/10 ha 1. Forest park Arkhiereyskaya Roshcha 44.7 6 1.3 Average population density M ± SE 1.3 2. Recreational park Pobedy Park 11.4 8 7.0 3. Kotofey Park 3.1 4 12.9 4. Park between the Vezelka River, Vatutina Ave., Pobedy St. and Popova St. 4.7 2 4.3 5. Lenin Park of Culture and Leisure 26.0 2 0.8 6. Pamyati Park 15.4 2 1.3 7. Pushkinskaya Allée 6.5 2 3.1 8. Yuzhny Park 6.8 1 1.5 Average population density M ± SE 2.8 ± 1.6 9. Cemetery Yachnevo Cemetery* 28.3 3 1.1 10. Mikhaylovskoe Cemetery 1.0 1 10.0 Average population density M ± SE 1.4 11. Small-house areas Between Plekhanova St., Gorkogo St., Vostochnaya St., Lesnaya St. 13.1 0 0 12. Between Plekhanova St., Transportnaya St., Zhukovskogo St., Tsiolkovskogo St., Lermontova St. 15.8 0 0 13. Between Krasnoarmeyskaya St., Belinskogo St., Grazhdanskaya St., 3-y Krasnoarmeysky Lane 25.1 0 0 Average population density M ± SE 0 14. Squares and boulevards Square near the Government building 0.5 1 20.0 15. Square near the Shchepkin Drama Theatre 1.4 0 0 16. Svyato-Troitsky Boulevard 2.2 0 0 17. Ioasafovsky Square 0.8 0 0 Average population density M ± SE 2.0 18. Green residential areas with predominantly 5-story housing blocks Between B. Khmelnitskogo Ave., Shershneva St., Nekrasova St., Studencheskaya St. 18.0 3 1.7 19. Between B. Khmelnitskogo Ave., Nekrasova St. 15.7 1 0.6 20. Between Mokrousova St., Kostyukova St., Shchorsa St. 31.2 4 1.3 Average population density M ± SE 1.2 ± 0.3 Note: * censuses carried out on a part of the cemetery area. 224 Lykov E. L. Table 3. Comparative population density of the woodpigeon (Columba palumbus L.) in European urban areas. Population density, pairs/10 ha City/town, country (year, habitat, location) Source More than 100 Legnica, Poland (2003–2004, down-town Central Park) Tomiałojć 2007 50–99 Słupsk, Poland (1990–1997, urban parks); Legnica, Poland (1966–1967, 1972, down-town Central Park); Wrocław, Poland (1970–1973, Słowacki Park) Gorski et al. 1998, Tomiałojć 2007, Tomiałojć et al. 2020 40–49 London, Great Britain (1974, St James’s Park); Zielona Góra, Poland (parks) Tomiałojć 1978, Bocheński et al. 2013 30–39 Legnica, Poland (2006, cemetery) Jędro et al. 2008 20–29 Słupsk, Poland (1985–1989, urban parks); Legnica, Poland (2004–2005, cemetery); Wrocław, Poland (2009, 2013, Południowy Park; 2007, Botanic Garden) Gorski et al. 1998, Jędro et al. 2008, Kopij & Zendwalewicz 2009, Kopij 2010, Tomiałojć et al. 2020 10–19 London, Great Britain (1974, Kensington Gardens); Wrocław, Poland (2009–2010, Szczytnicki Park; 2008–2010, Słowacki Park; 2013, Botanic Garden); Warsaw, Poland (2015, Krasińskich Garden); Mezőhegyes, Hungary (2022) Tomiałojć 1978, Tomiałojć 2011, Luniak & Węgrzynowicz 2019, Tomiałojć et al. 2020, Csathó & Bozó 2022 8–9.9 Słupsk, Poland (1974–1977, 1990–1997, suburban parks); Siedlce, Poland (1999, cemetery at Cmentarna St.) Gorski et al. 1998, Kasprzykowski & Łuczak 2000 6–7.9 Lublin, Poland (1988–1990, Akademicki Park; 1989–1991, Botanic Garden; 1989–1991, area planted with trees in Czechów); Słupsk, Poland (1985–1989, suburban parks); Liverpool, Great Britain (1996–1998, Sefton Park); Legnica, Poland (1965, Peripheral park); Košice, Slovakia (2011–2012, Cemetery of St. Rozália) Biadun 1994, Gorski et al. 1998, Slater 2001, Tomiałojć 2007, Mošanský et al. 2014 4–5.9 Lublin, Poland (1988–1990, Saski Garden Park); Legnica, Poland (2007, Peripheral park); Wrocław, Poland (2011, Biskupiński Park; 2008, Osobowice Cemetery; 2016, city center); Zielona Góra, Poland (residential area); Warsaw, Poland (2000, Мausoleum of the Soviet Soldiers Cemetery, estate near Dąbrowskiego St.; 2004– 2005, 2014, Skaryszewski Park); Battonya, Hungary (2022) Biadun 1994, Luniak et al. 2001, Tomiałojć 2007, Bocheński et al. 2013, Luniak & Węgrzynowicz 2019, Tomiałojć et al. 2020, Csathó & Bozó 2022 2–3.9 Lublin, Poland (1982–1984, cemetery at Lipowa St.; 1987–1989, cemetery at Unicka St.; 1987–1990, Bronowicki Park; 1988–1990, Majdanek Cemetery, Kalinowszczyzna Cemetery); Słupsk, Poland (1974–1977, urban parks); Siedlce, Poland (1985, Main Siedlce Park; 1984, 1986, Wild Siedlce Park; 1998, cemetery at Cmentarna St.; 1985–1986, 1998–1999, cemetery at Janowska St.); Kaliningrad, Russia (2008–2010); Kraków, Poland (2012, Rakowice Cemetery); Košice, Slovakia (2011–2012, park in Barca); Białystok, Poland (2013, parks); Wrocław, Poland (2017, built-up area); Warsaw, Poland (2006, 2013, Żeromskiego Park; 2013, Krasińskich Garden); Końskie, Poland (2016–2017, housing blocks area) Biadun 1994, Gorski et al. 1998, Dombrowski & Łuczak 1998, Kasprzykowski & Łuczak 2000, Astafieva et al. 2011, Albrycht & Ciach 2013, Mošanský et al. 2014, Zbyryt 2014, Kopij 2017, Luniak & Węgrzynowicz 2019, Dębowski 2020 1–1.9 Lublin, Poland (1982–1984, Ludowy Park); Siedlce, Poland (1984, 1986, Main Siedlce Park; 1985–1986, cemetery at Cmentarna St.); Dijon, France (1980–1984, Parc des Sports); Košice, Slovakia (2011–2012, Public Cemetery); Białystok, Poland (2013, city center, old housing blocks area, small-house area); Warsaw, Poland (2004, 2017, Żeromskiego Park; 2013, Kępa Potocka Park); Oryol, Russia (2019, 2021, forest parks, cemeteries) Biadun 1994, Dombrowski & Łuczak 1998, Tomiałojć 1998, Kasprzykowski & Łuczak 2000, Mošanský et al. 2014, Zbyryt 2014, Luniak & Węgrzynowicz 2019, Lykov& Sviridov 2024 less than 1 Dijon, France (1980, Parc de La Colombiere); Warsaw, Poland (late 1980s, Łazienki Park, Rakowiec, Wierzbno districts; 2006, Kępa Potocka Park); Košice, Slovakia (2011–2012, park on Komenského St.); Wrocław, Poland (2017, industrial area); Białystok, Poland (2013, new housing blocks area, industrial areas, suburban rural habitats); Oryol, Russia (2019, 2021, parks, small-house areas, green residential areas) Tomiałojć 1998, Luniak et al. 2001, Mošanský et al. 2014, Kopij 2017, Zbyryt 2014, Luniak & Węgrzynowicz 2019, Lykov & Sviridov 2024 The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, 225 the hooded crow. Thus, the population density of the magpie was 1.9 pairs/10 ha in the green residential areas with predominantly five-story housing blocks, while it was not recorded breeding on the census plots in the small-house areas. It should be noted that, despite the absence of breeding hooded crows and magpies on the census plots in the small-house areas, the common wood pigeon was not observed as a breeding species in this habitat, while there were places suitable for its breeding. At the same time, the censuses of breeding pairs of the species in the small-house areas were less complete than in other habitats due to the large area occupied by this habitat in the city (Table 1). Therefore, occasional breeding of the birds in this habitat should not be ruled out. Discussion Population density The common wood pigeon successfully exploits the urban environment by adapting to the extreme conditions of the city. Values of the population density in different urban habitats reflect the degree of association of birds with anthropogenic habitats. The higher population density of the species in most European urban areas compared to Belgorod is most likely due to the relatively short history of the urban population of the species in the city under study. In addition, the population density of the common wood pigeon is also affected by predation pressure and the proximity of agricultural lands where birds fly to feed (Tomiałojć 1976, 1979, 2021). These factors are discussed separately in the relevant sections of this paper. Being a species closely associated with trees, the common wood pigeon has a strong preference for green spaces, which likely explains the fact that its population density is the highest in the recreational parks of Belgorod. The average recorded population density of the common wood pigeon in parks of Belgorod is comparable with the density in Bronowicki Park in Lublin in 1987–1990, in Main Siedlce Park in 1985 and Wild Siedlce Park in 1984 and 1986 in Siedlce, in the parks of Białystok in 2013 and in Rakowice Cemetery in Kraków in 2012, while the average density in the Belgorod cemeteries is comparable with the density in the public cemetery in Košice in 2011–2012, in cemeteries of Oryol in 2019 and 2021, in Ludowy Park in Lublin in 1982–1984 and in Main Siedlce Park in Siedlce in 1984 and 1986 and that in the green residential areas with predominantly five-story housing blocks is comparable with the density in the green residential areas in the city of Oryol (Table 3). In Belgorod, as in other cities (e.g. Wrocław, Białystok, Zielona Góra), the population density of the common wood pigeon is significantly higher in parks compared to built-up areas (Kopij 2010, Tomiałojć 2011, Bocheński et al. 2013, Zbyryt 2014, Kopij 2017, Tomiałojć et al. 2020). Similar data were obtained in Rabat, where the high urban park coverage increases the probability of the species nest occurrence probability (Eddajjani et al. 2024). The information on the breeding of the common wood pigeon in natural habitats of the Belgorod Region is extremely fragmentary. The numbers of the species have increased notably in the region under consideration and adjacent territories over the past decades. For example, the species was not recorded breeding in the Vorskla Forest sector of Belogorye State Nature Reserve in 1963 and 1993, but was found there in 2008–2009 (Sokolov 2010). In the neighbouring Voronezh Region, the population density of the common wood pigeon in the Khrenovsky pine forest was 1 pair/km2 in 2010 and 2 pairs/ km2 in 2011 (Sokolov 2021). Table 4. Placement of nests of the woodpigeon (Columba palumbus L.) in trees in the green residential areas with predominantly five-story housing blocks in Belgorod. Taxon Number of nests % Linden (Tilia spp.) 7 25.9 Birch (Betula spp.) 4 14.8 Horse chestnut (Aesculus hippocastanum) 4 14.8 Poplar (Populus spp.) 2 7.4 Black locust (Robinia pseudoacacia)2 7.4 Elm (Ulmus spp.) 2 7.4 Ash (Fraxinus excelsior)1 3.7 Cherry (Prunus cerasus)1 3.7 Unidentified tree 4 14.8 226 Lykov E. L. Thus, the above data indicate a significantly higher population density of the common wood pigeon in the urban habitats of Belgorod compared to natural habitats. Nest placement Previous studies have shown that nest placement in the common wood pigeon had a significant impact on nest predation levels (Ó hUallacháin, 2014). In Belgorod, most nests are located in linden, birch and horse chestnut trees. In Kaliningrad, where a stable urban population of the species has formed over the past few decades (Lykov 2009a, Astafieva et al. 2011), linden was used most often for nesting in the green residential areas (19.8% of the total number of nests in this habitat: Lykov 2009b). In Minsk, the situation with preferences for nest tree type is similar: 55.1% of the common wood pigeon nests in the city neighbourhoods are located in linden (Sakhvon & Kövér 2020). The majority of nests are also located in linden in Liverpool in the UK, in Legnica in Poland and in Galway in Ireland (32%, 26.4% and 19.5% of nests, respectively: Tomiałojć 1979, Slater 2001, Ó hUallacháin 2014). In the residential area of Belgorod, only broadleaf trees were used by the common wood pigeon for nesting. Coniferous trees and shrubs are very rare in the city’s residential areas. In other cities where coniferous tree species are present in green spaces, the proportion of nests located on such trees can reach 25% (Kaliningrad: Lykov 2009b). No nests were noted on human buildings. The average height above the ground of nests of the common wood pigeon in the residential areas of Belgorod was 11.1 m. In other cities nests were, on average, located at a lower height: at 7.2 m in Debrecen (residential areas: Juhász & Varga 2019), at 6.0 m in Galway (university area: Ó hUallacháin 2014), at 5.4 m in Kaliningrad (residential areas: Lykov 2009b). In Szczytnicki Park in Wroclaw, the average nest height of 10.9 m is comparable with our data obtained in Belgorod. The average nest height of the common wood pigeon in another park in Wroclaw (Słowacki Park) was lower than in Belgorod (9.9 m), while that in the city park of Legnica was higher (14.3 m: Tomiałojć 1979). The higher nest placement in Belgorod compared to other cities and towns may be due to the very low numbers of the hooded crow, which is considered a principal nest predator of the common wood pigeon. With a high level of hooded crow predation, the birds place their nests lower above the ground (Tomiałojć 1979). In general, the location of the common wood pigeon nest in Belgorod low above the ground in a low-growing ornamental Norway maple is not unique for urban populations of common wood pigeons. Similar nests of this species, located low in ornamental trees, are not rare in the central part of Kaliningrad (Lykov 2023). Impact of major nest predators The hooded/carrion crow and, to a lesser extent, magpie are the principal nest predators of the common wood pigeon (Cramp 1972, Gorski et al. 1998, Tomiałojć 1976, 1978, 1998, 2005, Jędro et al. 2008, Vuorisalo 2010, Zbyryt 2014, Varga & Juhász 2020). In Belgorod, the breeding density of the hooded crow is very low, which is a favourable condition for the breeding of the common wood pigeon. However, the magpie, also a nest predator, breeds in the city with a higher density than the hooded crow. The breeding success of the species in some urban areas can drop as low as 3–7% due to predation pressure (Tomiałojć 2021). As noted by Tomiałojc (1978), the population density of the common wood pigeon is inversely proportional to the number of the hooded crow. Assessment of the food supply The main factor determining the breeding season of the common wood pigeon is food availability. In the cities, it feeds on grass growing on lawns in public gardens, roots, buds and leaves of trees and shrubs, seeds and flowers, while in autumn it feeds also on fruits, berries and acorns. Birds consume food on the ground, in trees and bushes (Cramp 1972, Hewlett 2002, Vuorisalo 2010, Bendjoudi et al. 2015, Gutiérrez-Galán et al. 2016, Luna & Blanch 2024). The species has also been reported to feed on urban green roofs (Luna & Blanch 2024). In this context, urban green areas might offer abundant and predictable feeding resources during the first stages of the breeding season, migration and wintering of birds. The common wood pigeon shows great plasticity in its foraging behaviour and exploits a wide range of resources from city trees (Luna et al. 2024). In addition, urban populations of the common wood pigeon are characterised by long-distance foraging movements outside the urban area to agricultural fields, where the birds receive additional food (Tomiałojć 1976, 2021, Slater 2001, Jędro et al. 2008, Astafieva 2009). During such movements, birds can cover regularly distances of up to 15 km or more from the nest (Tomiałojć, 1976). In the agricultural landscape, the common wood pigeon feeds The Current State of the Urban Population of the Common Wood Pigeon (Columba palumbus L.) in Belgorod, 227 on fields of wheat (Triticum spp.), rye (Secale cereale), barley (Hordeum vulgare), rape (Brassica napus), sunflower (Helianthus annuus) and peas (Lathyrus oleraceus). The main type of food in the agricultural landscape is grain and young shoots of cultivated cereals (Slater 2001, Astafieva 2009, Vuorisalo 2010, Mischenko et al. 2013, Csathó & Bozó 2022). The disappearance of agricultural fields during active urbanisation is the main limiting factor for the colonisation of an urban area by the common wood pigeon (Dinetti et al. 2013). In addition, birds stop feeding in abandoned fields (Mischenko et al. 2013). As of 2022, the most widespread crops in the Belgorod Region are winter wheat (Triticum aestivum, 30% of the total cultivated area), soybeans (Glycine max, 20%), sunflower (Helianthus annuus, 11.3%) and corn (Zea mays, 8.7%) (Federal State Statistics Service Regional Office of the Belgorod Region 2024b). Within the city limits, there are agricultural zones occupied by arable land (mainly in Zapadny District), vegetable gardens (in all districts of the city) and greenhouse facilities (in Vostochny District of the city) (Supporting Materials for the General Plan for the Development of the City of Belgorod Urban District until 2025 2019). The city of Belgorod is surrounded on all sides by Belgorodsky District, which has a total area of 1474.7 km2. Agriculture is well developed in the district, with 17 large agricultural enterprises in operation. The area of arable land used by economic entities in Belgorodsky District is 684 km2. Cereals, soybeans and sugar beets (Beta vulgaris) are the predominant crops (Website of Belgorod District municipal entity of the Belgorod Region 2024). Colonisation of urban areas The colonisation of cities by most bird species occurs gradually from the weakly transformed periphery of the city to its urbanised centre (“gradual synanthropisation”). The common wood pigeon belongs to a group of birds that colonise cities gradually (Lykov 2021a). Tomiałojć (1976) developed a scale for determining the stage of synanthropisation of the common wood pigeon, using information on the frequency of breeding of the species in habitats with different anthropogenic loads. The urban population of the species in Belgorod can be conditionally classified as of the synanthropisation stage 3: breeding in urban parks with a high density, as well as regular breeding in residential areas (on the streets). To date, the studied population in Belgorod has not reach the final synanthropisation stage 4, when the species breeds at a high density in urban parks, as well as in residential areas and individual pairs start to build nests on man-made structures. The final 4th stage of synanthropisation has been reached by urban populations of the common wood pigeon in London, Berlin, Wrocław, Legnica, Kaliningrad (Tomiałojć 1976, Hewlett 2002, Lykov et al. 2012). In the future, we can expect an increase in the population density of the species in Belgorod and breeding of individual birds on human buildings. Conclusion The data we obtained on the common wood pigeon distribution across habitats in the city, population density and nest locations indicate the formation of an urban population of the species in Belgorod. The population is at one of the final stages of synanthropisation. The coming decades may see an increase in the population density of the common wood pigeon in Belgorod. The species was recorded during the breeding season in all the studied habitats of the city, with the exception of the small-house areas. It also breeds in the central part of the city. The highest population density was recorded in parks. The lower population density of the common wood pigeon in Belgorod compared to most European urban areas is most likely due to the short history of the local urban population. The exact time of the emergence of the urban population of the common wood pigeon is unknown; however, the population existed as early as the early 1990s, with birds found breeding in park stands in the central part of the city (N.Yu. Belov, unpublished). The favourable factors that led to the emergence of the urban population of the species in Belgorod include the very low numbers of the hooded crow, the main nest predator, as well as the presence of vast agricultural fields in suburban areas, which apparently serve as a regular foraging ground for the birds. Acknowledgements: We would like to express our gratitude to N.Yu. Belov, the assistant director for general affairs of the St. Petersburg State Budgetary Cultural Institution “Leningrad Zoological Park”, for providing information on the breeding of the common wood pigeon in Belgorod in the previous period. References Albrycht M. & Ciach M. 2013. Changes in the breeding avifauna of the Rakowice Cemeteryin Kraków over last 40 years. Ornis Polonica 54: 247-256. (In Polish with English summary).