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1

Song repertoires in a western European population of Yellowhammers Emberiza citrinella

100%
Caro S. P., Keulen C., Poncin P.
Acta Ornithologica
|
2009
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tom 44
|
nr 1
Geographic variation is one of the most intensively studied bird song topics. However, our knowledge of geographical song variations in most species studied so far is very sparse, with many areas of the species-typical geographic distributions still unexplored. One striking example is the Yellowhammer: for this species most song studies have been conducted along well defined dialect borders, but almost nothing is known about its song characteristics in other regions of its broad geographic distribution. In this study, we investigated the song structure variations and stereotypes in different areas of western Belgium and northern France. We described 66 different song types (а-elements) in 45 males recorded. Each male had a unique individual repertoire consisting of 1 to 4 of these song types. This high variability at the individual level contrasted with the high homogeneity of the specific repertoire over the whole geographic distribution of the species. The evolutionary implications of such specificity are discussed with regard to song learning and timing of singing activity. Finally, all males recorded belonged to the western regiolect, although some mixed- singers were also recorded. These results contrast with the very few studies previously conducted in western Europe which have suggested that eastern regiolect songs were common in this geographic area.
2

Interspecific feeding of a Great Grey Shrike [Lanius excubitor] fledgling by adult Yellowhammers [Emberiza citrinella]

84%
Drozdz R., Hromada M., Tryjanowski P.
Biological Letters
|
2004
|
tom 41
|
nr 2
185-187
3

Changes in population size of the Yellowhammer [Emberiza citrinella] in farmland of Western Poland

84%
Tryjanowski P.
The Ring
|
1997
|
tom 19
|
nr 1-2
4

The importance of winter catch crops compared with other farmland habitats to birds wintering in Poland

67%
Golawski A., Kasprzykowski Z., Jobda M., Duer I.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 2
The study examined the importance of winter catch crops (intercrops) to wintering birds in a low-intensity farming area of Poland. Birds were counted on two occasions between November 2009 and January 2010 in 514 research plots in two different parts of the country. During the two counts 28 species were recorded. Yellowhammer Emberiza citrinella, Corn Bunting Emberiza calandra, Tree Sparrow Passer montanus and Shorelark Eremophila alpestris were the most numerous species. The statistical analysis (GLZ) of the influence of survey, location and habitat types on the occurrence of birds in the farmland did not reflect the significant effect on any variables. Significant differences in densities of birds between the habitats analysed (GLM) were noted. The stubbles supported a relatively greater density of birds than the mustard winter catch crop and ploughed fields. Increasing the area of winter catch crops at the expense of ploughed fields may favour birds, but when winter crops are sown in fields that would otherwise be left as stubble, wintering conditions for birds deteriorate, especially for buntings.
5

Agri-environment scheme habitat preferences of Yellowhammer Emberiza citrinella on English farmland

67%
McHugh N. M., Goodwin C. E. D., Hughes S., Leather S. R., Holland J. M.
Acta Ornithologica
|
2016
|
tom 51
|
nr 2
Agri-Environment Schemes (AES) have been implemented across Europe in an attempt to address biodiversity losses associated with agricultural intensification. For many declining farmland bird species, the reduced availability and suitability of nesting and foraging habitats are thought to play a major role in population declines and some AES have hoped to counteract this by encouraging the provision of such habitats. This study aimed to determine the relative importance of AES on the territory selection of a widespread but declining farmland bird, the Yellowhammer Emberiza citrinella. Yellowhammers were more likely to locate territories in areas containing 'enhanced margins'; i.e. where field margin habitats were sown with wild flowers and/or agricultural legumes. An average of 0.033 ± 0.008 ha of this 'enhanced margin' habitat was present within 100 m of Yellowhammer territories compared to 0.020 ± 0.008 ha within 100 m of random points. This preference may reflect the higher invertebrate chick food abundance associated with this habitat as they contained, on average 46.3% and 36.8% more invertebrate food items than cereal and floral crops respectively. Alternatively, given that chick food abundance was similar between grass and enhanced field margins, this observed preference may be the result of a more open sward structure which increases prey accessibility and improves predator avoidance. Yellowhammers selected territories containing early succession hedgerows, as these constitute the most suitable nesting sites, and preferred territories containing a suitable songpost. Our results suggest that management strategies aiming to conserve breeding Yellowhammers should focus on increasing the coverage of invertebrate rich AES habitats such as floristically-enhanced margins and pollen and nectar plots, and ensure that they are located within typical foraging ranges of cut hedges with elevated songposts.
6

Changes in breeding populations of six farmland bird species in Western Poland between 1987 and 2007

59%
Krajewska A., Mizera T.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 3
The breeding populations of the Skylark Alauda arvensis, Yellowhammer Emberiza citrinella, Corn Bunting Miliaria calandra, Yellow Wagtail Motacilla flava, Whinchat Saxicola rubetra, and Red-backed Shrike Lanius collurio were censused by the mapping method on 315 ha of intensive farmland in W Poland. Results obtained in 2006 and 2007 were compared with previously published data from 1987 to 1997. Changes in habitat structure, mainly the decline of margin habitats, and the intensification of agricultural production, which both occurred between the two study periods, affected breeding bird populations; M. flava showed drastic long-term decreasing trends, and M. calandra increased significantly in number. The other four species showed year-to-year variation rather than directional trends. Numbers of A. arvensis declined from 1987 to the late 1990s and subsequently increased. Generally, population trends of the studied species were similar to those in other long-term study plots in Poland but differed from trends in Western Europe.
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