Habitat type, food resources, noise and light pollution explain the species composition, abundance and stability of a winter bird assemblage in an urban environment

Abstract

At present, urban areas cover almost 3% of the Earth's terrestrial area, and this proportion is constantly increasing. Although urbanization leads to a decline in biodiversity, at the same time it creates extensive habitats that are exploited by an assemblage of organisms, including birds. The species composition and density of birds nesting in towns and cities are determined by the types of buildings, the structure and maturity of urban greenery, and habitat diversity. In contrast, the habitat traits shaping the community of birds wintering in urban areas are not known. The aim of this work was to assess the influence of habitat structure, food resources and the urban effects (pollution, noise, artificial light) on an assemblage of birds overwintering in an urban area. It was carried out in 2014 and 2015 in the city of Kraków (southern Poland), on 56 randomly chosen sample plots, in which the composition, density and interseasonal similarity of bird assemblage were assessed with line transect method. A total of 64 bird species (mean = 17.7 ± 4.9 SD species/plot) was recorded. The mean density was 89.6 ind./km ±63.3 SD. The most numerous species were Great Tit Parus major, Magpie Pica pica, Blackbird Turdus merula, Blue Tit Cyanistes caeruleus, Rook Corvus frugilegus, Fieldfare Turdus pilaris and House Sparrow Passer domesticus. Noise adversely affected species numbers and density, but artificial light acted positively on the density of birds and their interseasonal stability. The species richness and density of birds were also determined by the number of food sources available (e.g. bird-feeders). In addition, the greater the proportion of open areas, the fewer species were recorded. In contrast, the more urban greenery there was, the greater the density of the entire bird assemblage. Urban infrastructure (buildings, roads, refuse tips) had a positive effect on the interseasonal stabilization of the species composition of wintering birds. The results of this work indicate that the urban effect, i.e. noise and light pollution, apart from purely habitat factors, provide a good explanation for the species richness, density and stability of bird assemblage wintering in urban areas.

Temporally Stable Species Occupancy Frequency Distribution and Abundance–Occupancy Relationship Patterns in Urban Wintering Bird Assemblages

“…We investigated the SOFD and SAOR patterns of urban wintering bird communities during three winters (1991-1992, 1999-2000, and 2009-2010) in small and large human settlements located in southern and northern Finland by using the same study plots and survey methods. Some previous studies have examined shortterm temporal variability of urban bird assemblages Ciach, 2012). These studies have found that the diversity of wintering bird assemblages decreased with urbanization (Ciach, 2012), stability of winter bird communities decreased from the center of the town towards the periphery of the town (Jokimäki and Kaisanlahti-Jokimäki, 2012;Leveau et al, 2015), and between-year variability of bird richness and abundance were greatest during the nonbreeding season (Leveau et al, 2015).…”

“…However, temporal variation of the wintering bird assemblages is much less studied. Previous studies have detected only a slight variation in bird species richness and total number of individuals between winters, suggesting that urbanization might stabilize temporal variation of urban bird assemblages Jokimäki and Kaisanlahti-Jokimäki, 2012;Ciach and Fröhlich, 2017). It has been suggested that urban attributes, such as winter feeding of birds, roads, light, and buildings, will stabilize temporal variation of wintering bird assemblage within city (Ciach and Fröhlich, 2017).…”

“…It has been suggested that urban attributes, such as winter feeding of birds, roads, light, and buildings, will stabilize temporal variation of wintering bird assemblage within city (Ciach and Fröhlich, 2017). However, Ciach (2012) detected that wintering bird species diversity decreased in an urbanizing area in southern Poland during 2005-2010. Apparently, more long-term winter-time studies are needed to understand a more detailed temporal dynamic of bird assemblages, such as species occupancy frequency distribution (SOFD) and species abundance-occupancy relationship (SAOR) patterns.…”

Relationship of bird richness, abundance and assemblage to the built environment in a small island tropical urban setting: a Suva, Fiji case study

“…Vegetation on, or around, buildings has been shown to be related to urban bird composition (Deng and Jim 2007;Belcher et al 2018), as has the size, height and variability of building height (MacGregor-Fors and Schondube 2011;Pellissier et al 2012). Other factors include habitat type and food resources (Lim et al 2003;Lerman and Warren 2011), noise (Fontana et al 2011;Proppe et al 2013) and light pollution (Ciach and Fröhlich 2007).…”

Annual dynamics of bird communities in urban parks in Lviv, Ukraine: preliminary analysis of diversity and composition variability

“…This reveals why birds are common objects in ecological studies, especially in urban habitats. From the view of avifauna, it is impossible to consider the city as a single whole, and in most research the city is considered as a complexity of different habitat types [2,6,9] that makes synurbization processes easier to study in birds.…”