Seasonal changes in avian communities living in an extensively used farmland of Western Poland

To study the seasonal changes in avian communities, we collected data in an extensively used farmland in Western Poland during 2006-2013. Generalized additive mixed models were used in order to study the effects of seasonality and protected areas on the overall bird species richness. A similarity percentage analysis was also conducted in order to identify the species that contribute most strongly to dissimilarity among each bird according to the phenological season. Furthermore, the differences in bird communities were investigated applying the decomposition of the species richness in season, trend, and remainder components. Each season showed significant differences in bird species richness (seasonality effect). The effect of the protected areas was slightly positive on the overall species richness for all seasons. However, an overall negative trend was detected for the entire period of eight years. The bird community composition was different among seasons, showing differences in terms of dominant species. Greater differences were found between breeding and wintering seasons, in particular, the spatial pattern of sites with higher bird richness (hotspots) were different between breeding and wintering seasons. Our findings showed a negative trend in bird species richness verified in the Polish farmlands from 2006. This result mirrors the same negative trend already highlighted for Western Europe. The role of protected areas, even if slightly positive, was not enough to mitigate this decline process. Therefore, to effectively protect farmland birds, it is necessary to also consider inter-seasons variation, and for this, we suggest the use of medium-term temporal studies on bird communities’ trends

The effect of climate change on avian offspring production: A global meta-analysis

Climate change affects timing of reproduction in many bird species, but few studies have investigated its influence on annual reproductive output. Here, we assess changes in the annual production of young by female breeders in 201 populations of 104 bird species (N = 745,962 clutches) covering all continents between 1970 and 2019. Overall, average offspring production has declined in recent decades, but considerable differences were found among species and populations. A total of 56.7% of populations showed a declining trend in offspring production (significant in 17.4%), whereas 43.3% exhibited an increase (significant in 10.4%). The results show that climatic changes affect offspring production through compounded effects on ecological and life history traits of species. Migratory and larger-bodied species experienced reduced offspring production with increasing temperatures during the chick-rearing period, whereas smaller-bodied, sedentary species tended to produce more offspring. Likewise, multi-brooded species showed increased breeding success with increasing temperatures, whereas rising temperatures were unrelated to repro- ductive success in single-brooded species. Our study suggests that rapid declines in size of bird populations reported by many studies from different parts of the world are driven only to a small degree by changes in the production of young

Does the White Stork Ciconia ciconia reflect farmland bird diversity?

The White Stork (Ciconia ciconia) is an icon of nature protection and one of the easiest birds to monitor, particularly in Central Europe. Here avian biodiversity was compared between sites (territories) occupied by nesting White Storks and sites that were formerly occupied but were unoccupied during the two study years, and often for several preceding years. The study was conducted in Western Poland during two breeding seasons, 2007 and 2008, involving 43 and 54 territories, respectively. Moreover, information on nest oc-cupancy and breeding success of White Storks since 2005 was used as a measure of habi-tat quality. Breeding bird diversity was significantly higher in occupied than in unoccu-pied White Stork territories. Bird diversity was also higher in territories with better White Stork chick productivity in the period 20052008. Even greater differentiation in bird di-versity might have been achieved between occupied White Stork territories and random sampling points in similar habitat

Diurnal raptor community wintering in an extensively used farmland

The raptor community wintering in an extensively managed farmland was studied in Western Poland during seven winters (20062013). Data on raptor presence and numbers was obtained by point count method. In the presented paper we focus on the variance in abundance and habitat selection of diurnal predators: Common Buzzard (Buteo buteo), Rough-legged Buzzard (Buteo lagopus), Common Kestrel (Falco tinnunculus), Eurasian Sparrowhawk (Accipiter nisus), Northern Goshawk (Accipiter gentilis) and Great Grey Shrike (Lanius excubitor). Study species were governed by two major habitat gradients in farmland: from amount of mowed meadows towards increasing coverage of arable fields and from non-mowed meadows and shrubs towards increasing coverage of forests. Par-ticular species differed in response to habitat variables: plots with large coverage of mead-ows and high heterogeneity were preferred by Rough-legged Buzzard and Common Kes-trel. Great Grey Shrike and Northern Goshawk selected linear habitats, mostly shrub lines, and non-mowed meadows while Eurasian Sparrowhawk was associated with fo-rests and urban areas. Rough-legged Buzzard avoided arable fields, while Common Buz-zard had broader preferences and was more associated with arable fields. We also found that Common Buzzard and Great Grey Shrike abundance was positively related with win-ter temperature, while Rough-legged Buzzard showed a negative relationship. Our study shows the importance of heterogeneity in farmland as well as meadows as optimal habi-tats for wintering raptors, and we underline the role of extensive agriculture in conserva-tion of raptors

Village modernization may contribute more to farmland bird declines than agricultural intensification

The central tenet of European farmland ecology is that agricultural intensification during the 20th century was largely responsible for dramatic declines in species abundances. However, during this time, human rural settlements were also undergoing radical changes through modernization, with undocumented biodiversity impacts in this important wildlife habitat. We performed the first ever large-scale study to disentangle the impact of these simultaneous processes on farmland bird diversity in 104 Polish villages. We show that modernized villages and their surrounding agricultural fields had 50-60% fewer birds than those in and around comparable older villages. The relative contribution of modernization versus agricultural intensification to predicted bird declines was 88% versus 12% for bird communities in villages and 56% versus 44% in surrounding croplands, with considerable variation among ecological species subgroups. These results challenge our current understanding of agricultural ecosystem ecology and how best to implement conservation measures costing billions of euros annually

Life in a polluted world: A global review of anthropogenic materials in bird nests

Human pressure exerts a significant influence on animals and the environment. One of its consequences, plastic pollution is considered one of the major threats to fauna as well as a significant conservation issue. In this research, we examined the global pattern of one example of avian behavior in response to pollution—namely, the incorporation of anthropogenic materials into nests—as well as the existing knowledge on this subject. Based on 25 articles, we studied 51 populations, involving 24 bird species, and checked 10,790 nests; as a result, we found that incorporation of debris is correlated with increasing human influence on the environment, measured as the Human Footprint Index. Moreover, the probability of debris incorporation is higher in terrestrial than in marine species. We also identified knowledge bias in favor of marine as opposed to terrestrial species: namely, marine species attract more scientific attention than terrestrial. Furthermore, research approaches to these two ecosystems differ. Undeniably, the factors which influence debris incorporation by birds, the scale of this behavior, and particular forms of use of debris in bird nests are aspects which require long-term standardized research. This is the first global review paper on debris incorporation by birds to demonstrate a close link to human pressure as a driver

Seasonal changes in avian communities living in an extensively used farmland of Western Poland

To study the seasonal changes in avian communities, we collected data in an extensively used farmland in Western Poland during 2006-2013. Generalized additive mixed models were used in order to study the effects of seasonality and protected areas on the overall bird species richness. A similarity percentage analysis was also conducted in order to identify the species that contribute most strongly to dissimilarity among each bird according to the phenological season. Furthermore, the differences in bird communities were investigated applying the decomposition of the species richness in season, trend, and remainder components. Each season showed significant differences in bird species richness (seasonality effect). The effect of the protected areas was slightly positive on the overall species richness for all seasons. However, an overall negative trend was detected for the entire period of eight years. The bird community composition was different among seasons, showing differences in terms of dominant species. Greater differences were found between breeding and wintering seasons, in particular, the spatial pattern of sites with higher bird richness (hotspots) were different between breeding and wintering seasons. Our findings showed a negative trend in bird species richness verified in the Polish farmlands from 2006. This result mirrors the same negative trend already highlighted for Western Europe. The role of protected areas, even if slightly positive, was not enough to mitigate this decline process. Therefore, to effectively protect farmland birds, it is necessary to also consider inter-seasons variation, and for this, we suggest the use of medium-term temporal studies on bird communities’ trends