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Open access

Jan M. Kaczmarek and Piotr Tryjanowski

Abstract

The development of cellulosic bioethanol and other second-generation (2G) biofuels has gone through various phases during the last few years. The prospect of technological breakthroughs stimulates extensive research on turning cellulose into bioethanol or biodiesel. Agricultural or forestry residues and some plants, referred to as ‘lignocellulosic energy crops’ or ‘second generation (2G) energy crops’ can provide feedstock for new types of biofuels. The impact of lignocellulosic energy crops on farmland birds has been relatively well studied. This is surprising since the technology of converting these crops into fuel has so recently been developed. However, we believe that some questions regarding potential bird use of 2G energy crops have still not been answered. In Europe, most research has been carried out in agricultural areas of Western Europe. However, Central & Eastern Europe host the highest densities of farmland birds and, in general, the highest biodiversity. There is huge potential for 2G energy cropping due to large areas of mainly marginal land. We have outlined possible discrepancies between the results obtained from W. Europe and potential relationships between birds and 2G energy crops in Central Europe.

Open access

Martin Hromada, Marcin Antczak and Piotr Tryjanowski

Abstract

Age of male is an important cue in mate selection, including extra-pair copulations; different phenotypic and behavioural traits are known to be age related. Paternity studies show that older males predominate as fathers of extra-pair young. It remains unclear if females actively choose older males because they possess high quality traits or because older males are more successful in coercing fertile females. We experimentally provided mounted males of different age (yearling vs. adult) of great grey shrike Lanius excubitor with nuptial gifts of different quality (vole vs. cricket) and observed reactions of females and their social partners. Females strongly preferred older males with energy-rich nuptial gifts. The reactions of females’ social partner to the extra-pair male did not differ significantly amongst experimental groups. However, males responded to the reaction of their mates and male aggressive behaviour increased when their mate showed an interest in an intruder.

Open access

Monika Fliszkiewicz, Aleksandra Langowska and Piotr Tryjanowski

Abstract

The red mason bee Osmia bicornis L. (Hymenoptera: Megachilidae) is a solitary gregarious species that is known to be a good pollinator of pear, apple, and several other Rosaceae fruit plants. Mainly females are active in plant pollination, and therefore they are of strong interest to farmers. As natural populations are usually male biased, here we studied the possibility of rearing a female-biased population of Osmia bicornis by examining the effects of sex ratio changes on female survival, insemination rate, and sperm count in the spermatheca. Using bees that had completed their winter diapause and were maintained in flying cages, we created three groups with different male:female sex ratios: 1:1, 1:2, and 1:3. The 1:3 sex-ratio group exhibited the best survival of females, but the lowest spermathecae sperm count. The insemination rate did not differ between groups. Our results indicate that-at least among bees housed in isolator cages for plant breeding- skewing the sex ratio towards more females does not affect bee survival, and efficient insemination can be expected with twice as many females as males.

Open access

Aleksandra Łangowska, Reuven Yosef, Piotr Skórka and Piotr Tryjanowski

Abstract

Bee-eaters (Meropidae) are considered agricultural pests and their presence provokes conflicts with beekeepers and farmers who rely on the pollination services of honey bees. This problem is often deal with through the mass killing of the birds, even though the quantitative evidence on the impact of bee-eaters on honey bee colonies is scarce. The current paper reports the performance of honey bee colonies protected with mist nets from migrating flocks of European bee-eaters Merops apiaster in Israel. In the study the weight gains of bee hives surrounded by mist nets were 6.44 times higher than that of unprotected hives (26.4 kg vs. 4.1 kg). The results confirmed that bee-eaters locally pose a problem to apiaries and potentially to the crops that require pollination. Mist- netting appeared to be an effective mitigation method for alleviating conflicts between beekeepers and bee-eaters. However, the study also showed that bees were able to differentiate between their main predator and other avian species trapped in mist nets and stung only bee-eaters. Moreover, the bees were targeting the most vulnerable body parts of birds which resulted in some bird fatalities. Therefore, due to accidental mortal- ity of birds, mist-netting is recommended only on the migratory routes in cases when bee hives cannot be moved to other areas.

Open access

Piotr Tryjanowski, Martin Hromada, Federico Morelli, Emma Nelson, Pavol Prokop, Luis Reino, Lajos Rozsa and Reuven Yosef

Open access

Zbigniew Kwieciński, Federico Morelli, Marcin Antczak, Martin Hromada, Paweł Szymański, Marcin Tobolka, Łukasz Jankowiak and Piotr Tryjanowski

Abstract

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.