Winter Bird Assemblages in Rural and Urban Environments: A National Survey

Abstract

Urban development has a marked effect on the ecological and behavioural traits of many living organisms, including birds. In this paper, we analysed differences in the numbers of wintering birds between rural and urban areas in Poland. We also analysed species richness and abundance in relation to longitude, latitude, human population size, and landscape structure. All these parameters were analysed using modern statistical techniques incorporating species detectability. We counted birds in 156 squares (0.25 km2 each) in December 2012 and again in January 2013 in locations in and around 26 urban areas across Poland (in each urban area we surveyed 3 squares and 3 squares in nearby rural areas). The influence of twelve potential environmental variables on species abundance and richness was assessed with Generalized Linear Mixed Models, Principal Components and Detrended Correspondence Analyses. Totals of 72 bird species and 89,710 individual birds were recorded in this study. On average (±SE) 13.3 ± 0.3 species and 288 ± 14 individuals were recorded in each square in each survey. A formal comparison of rural and urban areas revealed that 27 species had a significant preference; 17 to rural areas and 10 to urban areas. Moreover, overall abundance in urban areas was more than double that of rural areas. There was almost a complete separation of rural and urban bird communities. Significantly more birds and more bird species were recorded in January compared to December. We conclude that differences between rural and urban areas in terms of winter conditions and the availability of resources are reflected in different bird communities in the two environments.

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

“…Of prime importance to the species composition of breeding birds are the maturity and type of greenery (White et al 2005;Palomino and Carrascal 2006;Stagoll et al 2012), the size and fragmentation of habitats, as well as the degree to which an area is built up (Fernández-Juricic and Jokimäki 2001;Crooks 2004;Palomino and Carrascal 2006). The few papers dealing with the wintering period state only the following variables as influencing the species composition: habitat composition and geographical location (Tryjanowski et al 2015c), type of buildings (Jokimäki and KaisanlahtiJokimäki 2012), density of bird-feeders (Tryjanowski et al 2015b), density of buildings, density and height of trees and shrubs, length of woodland margin and distance to water and railway lines (Tilghman 1987). The present paper is the first to demonstrate that the urban effect (light and noise pollution) may shape bird assemblages wintering in urban areas.…”

“…In addition, some species that do not breed in urban areas nonetheless concentrate there in winter (Jokimaki et al 1996;Bellebaum 2005;Meissner et al 2012;Jadczyk and Drzeniecka-Osiadacz 2013), which increases their density significantly in comparison with non-urbanized areas (Lancaster and Rees 1979;Jokimaki et al 1996;Tryjanowski et al 2015c). …”

Urbanization affects neophilia and risk-taking at bird-feeders

“…All birds seen or heard were recorded using a point count with 5-min observations at each point4, and once again to reduce daily variation in the number of birds monitored 1–4 h after sunrise40. This standard bird census method was tested during winter conditions in Poland for species presence and detectability23, and it provides reliable information on relative density of birds41. Data from the three point counts were summed and used to describe the composition of the winter bird community in the immediate neighbourhood of each feeder.…”

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

“…During the winter season, at least in northern areas as in our case, wintering birds are mainly foraging on bird feeders, partly due to the low temperatures, a short daytime (4-6 h) and snow cover (Hurme, 1973). Because feeding sites are more abundant in urban than in more natural sites, most overwintering birds are concentrated in these sites within human settlements (Jokimäki and Suhonen, 1998;Tryjanowski et al, 2015). Also, a scare vegetation cover, due to the absence of leaves on deciduous trees and shrubs in winter, increases the visibility of birds.…”