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Demography of a common butterfly on humid grasslands: Argynnis aglaja [Lepidoptera: Nymphalidae] studied by mark-recapture

100%

Zimmermann K., Konvicka M., Fric Z., Cihakova V.

Polish Journal of Ecology

2009

tom 57

nr 4

715-727

Much of the research into the demography of butterflies conducted in Europe during the last few decades focused on rapidly declining or, on the other hand, expanding species, whereas species with stable trend tend to be neglected by researchers. Argynnis aglaja, a widely distributed inhabitant of semi-natural grasslands, represents a suitable model for studying patterns of landscape persistence of not-yet-threatened grassland insects. Using mark-recapture method conducted for one season on humid meadows in Western Bohemia, Czech Republic, we show that this large-bodied species is capable to form large and dense populations, reaching densities of over 250 individuals per hectare. The adults were relatively long-living, an average female longevity (11.8 d) was over twice as high as an average male longevity (4.6 d), with maxima being 22 (a male) and 30 (a female) days. The prolonged female lifespan is beneficial for a species that do not emerge with fully-matured eggs and oviposits singly over large areas. Modelling mobility, well-approximated by an inverse-power function, predicted that about one individual in a thousand would cross the distance of 1000 meters. We conclude that the satisfactory conservation status of A. aglaja stems from its capability to reach high local densities combined with a good dispersal power.

Conservation of farmland birds faces different challenges in Western and Central-Eastern Europe

45%

Tryjanowski P., Hartel T., Baldi A., Szymanski P., Tobolka M., Herzon I., Golawski A., Konvicka M., Hromada M., Jerzak L., Kujawa K., Lenda M., Orlowski G., Panek M., Skorka P., Sparks T. H., Tworek S., Wuczynski A., Zmihorski M.

Acta Ornithologica

2011

tom 46

nr 1

Birds are commonly used as an example of the strongly declining farmland biodiversity in Europe. The populations of many species have been shown to suffer from intensification of management, reduction of landscape heterogeneity, and habitat loss and fragmentation. These conditions particularly dominate farmland in the economically well developed countries of Western Europe. Currently, the farmland environment in Central-Eastern Europe is generally more extensive than in Western Europe and a larger proportion of people still live in rural areas; thus generating different conditions for birds living in agricultural areas. Furthermore, the quasi-subsistence farming in much of Central-Eastern Europe has resulted in agricultural landscapes that are generally more complex than those in Western Europe. To protect declining bird populations living in farmland, detailed knowledge on both species and communities is necessary. However, due to scientific tradition and availability of funding, the majority of studies have been carried out in Western Europe. In consequence this provokes a question: are findings obtained in western conditions useful to identify the fate of farmland bird biodiversity in Central-Eastern Europe? Therefore, the major goal of this paper is to highlight some local and regional differences in biodiversity patterns within EU farmland by comparing intensive agricultural landscapes with more extensive ones. More specifically, we aim to outline differences in agricultural landscapes and land use history in the two regions, use farmland birds to provide examples of the differences in species dynamics and species-habitat interactions between the two regions, and discuss possible social and ecological drivers of the differences in the context of biodiversity conservation. Factors governing spatio-temporal dynamics of farmland bird populations may differ in intensive and extensive landscapes as illustrated here using the Grey Partridge Perdix perdix and the Red-backed Shrike Lanius collurio as examples. The unevenness of farmland bird studies distribution across Europe was also presented. We call for more emphasis on pluralism in furthering both pan-European research on farmland bird ecology and conservation strategies. We also highlight some features specific to Central-Eastern Europe that merit consideration for the more efficient conservation of farmland birds and farmland biodiversity across Europe.

Ograniczanie wyników

1 Acta Ornithologica

1 Polish Journal of Ecology

2 Konvicka M.

1 Baldi A.

1 Cihakova V.

1 Fric Z.

1 Golawski A.

1 Hartel T.

1 Herzon I.

1 Hromada M.

1 Jerzak L.

1 Kujawa K.

1 Lenda M.

1 Orlowski G.

1 Panek M.

1 Skorka P.

1 Sparks T. H.

1 Szymanski P.

1 Tobolka M.

1 Tryjanowski P.

1 Tworek S.

1 Wuczynski A.

1 Zimmermann K.

1 Zmihorski M.

1 2011

1 2009

Wyniki wyszukiwania

Demography of a common butterfly on humid grasslands: Argynnis aglaja [Lepidoptera: Nymphalidae] studied by mark-recapture

Conservation of farmland birds faces different challenges in Western and Central-Eastern Europe