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Declines in European bird populations are reported for decades but the direct effect of major anthropogenic pressures on such declines remains unquantified. Causal relationships between pressures and bird population responses are difficult to identify as pressures interact at different spatial scales and responses vary among species. Here, we uncover direct relationships between population time-series of 170 common bird species, monitored at more than 20,000 sites in 28 European countries, over 37 y, and four widespread anthropogenic pressures: agricultural intensification, change in forest cover, urbanisation and temperature change over the last decades. We quantify the influence of each pressure on population time-series and its importance relative to other pressures, and we identify traits of most affected species. We find that agricultural intensification, in particular pesticides and fertiliser use, is the main pressure for most bird population declines, especially for invertebrate feeders. Responses to changes in forest cover, urbanisation and temperature are more species-specific. Specifically, forest cover is associated with a positive effect and growing urbanisation with a negative effect on population dynamics, while temperature change has an effect on the dynamics of a large number of bird populations, the magnitude and direction of which depend on species' thermal preferences. Our results not only confirm the pervasive and strong effects of anthropogenic pressures on common breeding birds, but quantify the relative strength of these effects stressing the urgent need for transformative changes in the way of inhabiting the world in European countries, if bird populations shall have a chance of recovering.

The concept of High Nature Value Farmland (HNVF) was introduced in the early 1990s to highlight the crucial role of low intensity farming systems for the conservation of biodiversity in Europe. HNVF is a biodiversity indicator and the maintenance or the enhancement of HNVF is a goal of the EU’s rural development policy. Several different approaches currently exist for identifying such areas, and a number of studies have shown that outcomes have often been unsatisfactory, at least as concerns biodiversity conservation. In this study, we use birds as indicators to assess the correlation between HNVF types identified according to the land cover approach and farmland areas important for biodiversity in Apulia, a southern Italian region that is among the most important in the Mediterranean area for farmland biodiversity. Our results suggest that unless the current land cover approach – which is mainly based on criteria relating to vegetation types and landscape structure – is accompanied by an objective analysis of local biodiversity levels, it risks excluding from HNVF some of the most important areas for biodiversity, thus reducing indicator effectiveness because of the lack of a proper assessment of HNVF extent and quality. Thus, our study shows a possible method to better identify HNVF type 3, thus increasing the effectiveness of the HNVF indicator.

Climate change is a major global threat to biodiversity with widespread impacts on ecological communities. Evidence for beneficial impacts on populations is perceived to be stronger and more plentiful than that for negative impacts, but few studies have investigated this apparent disparity, or how ecological factors affect population responses to climatic change. We examined the strength of the relationship between species-specific regional population changes and climate suitability trends (CST), using 30-year datasets of population change for 525 breeding bird species in Europe and the USA. These data indicate a consistent positive relationship between population trend and CST across the two continents. Importantly, we found no evidence that this positive relationship differs between species expected to be negatively and positively impacted across the entire taxonomic group, suggesting that climate change is causing equally strong, quantifiable population increases and declines. Species’ responses to changing climatic suitability varied with ecological traits, however, particularly breeding habitat preference and body mass. Species associated with inland wetlands responded most strongly and consistently to recent climatic change. In Europe, smaller species also appeared to respond more strongly, whilst the relationship with body mass was less clear-cut for North American birds. Overall, our results identify the role of certain traits in modulating responses to climate change and emphasise the importance of long-term data on abundance for detecting large-scale species’ responses to environmental changes.

Native parasitoids may play an important role in biological control. They may either support or hinder the effectiveness of introduced nonnative parasitoids released for pest control purposes. Results of a three-year survey (2011–2013) of the Asian chestnut gall wasp (ACGW) Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) populations and on parasitism rates by native indigenous parasitoids (a complex of chalcidoid hymenopterans) in Italian chestnut forests are given. Changes in D. kuriphilus gall size and phenology were observed through the three years of study. A total of 13 species of native parasitoids were recorded, accounting for fluctuating parasitism rates. This variability in parasitism rates over the three years was mainly due to the effect of Torymus flavipes (Walker) (Hymenoptera: Torymidae), which in 2011 accounted for 75% of all parasitoid specimens yet decreased drastically in the following years. This strong fluctuation may be related to climatic conditions. Besides, our data verified that parasitoids do not choose host galls based on their size, though when they do parasitize smaller ones, they exploit them better. Consequently, ACGWs have higher chances of surviving parasitism if they are inside larger galls.

In this study we investigated the phylogenetics of the Eurasian treecreeper (Certhia familiaris), a forest passerine with a wide Palaearctic range including Corsica, using three mitochondrial genes and three nuclear introns, and its phylogeographic history using the COI gene. Our phylogenetic results, including eight of the ten sub-species currently recognized, support the monophyly of C. familiaris with respect to its Indo-Asian sister species C. hodgsoni. C. familiaris comprises two lineages that diverged during the mid-Pleistocene (c. 1 Myr): one palaeoendemic lineage has an allopatric range nowadays restricted to the Corsica island and the Caucasus region whereas the second one, more recent and widespread, is distributed over most of Eurasia and in northern China. The most likely scenario that may explain such a pattern is a double colonization of the western Palaearctic from the eastern range of the species. During the middle Pleistocene period, a first lineage expanded its range up into Europe but did not persist through glacial cycles except in Corsica and the Caucasus region. Later, during the upper Pleistocene, a second lineage began to diversify around 0.09 Myr, spreading towards the western Palaearctic from a unique refuge likely located in the eastern Palaearctic [correction added on 6 March 2015 after first online publication: 0.9 Myr amended to 0.09 Myr]. Apart from C. f. corsa, our results do not suggest any distinct evolutionary history for other sub-species previously described on morphological grounds in Europe. Our study highlights the important conservation value of the Corsican treecreeper and emphasizes the major role of mature pine forests in the evolution of endemic bird taxa in Corsica. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 115, 134–153.

Negli ultimi anni e emersa sempre piu l’importanza delle aree verdi urbane per la conservazione della biodiversita, sebbene questa risulti assai variabile in funzione della struttura intrinseca dell’area verde, e del contesto paesaggistico in cui e immersa. Utilizzando struttura e composizione specifica dei popolamenti di uccelli, che vengono considerati buoni indicatori di biodiversita complessiva, abbiamo analizzato tre aree verdi urbane e periurbane della citta di Bari. Le tre aree sono assai diverse tra loro: i Giardini di Piazza Umberto sono l’unico giardino storico centrale della citta, il Parco 2 Giugno e invece situato vicino ai margini dell’area urbana, ed e di recente istituzione, infine Lama Balice e un’area a vegetazione spontanea mediterranea, situata in area periurbana. I censimenti di uccelli, svolti con due metodi complementari (punti di ascolto e metodo McKinnon) standardizzati, hanno permesso di confrontare correttamente le tre situazioni. La situazione registrata nelle tre aree appare ben delineata: passando dall’area piu periferica verso il centro si assiste a una drastica riduzione della biodiversita, misurata secondo tutte e tre le sue componenti (alfa, beta e gamma). Questa riduzione pare dipendere, oltre che dalla frammentazione e dall’isolamento delle due aree piu centrali, anche da fattori agenti a scala vasta; tra questi soprattutto la scarsita di specie ornitiche forestali che caratterizza tutta l’area barese, e pugliese in generale.

Distribution of Sylvia cantillans subspecies in Italy M. Brambilla et a . SHORT COMMUNICATION Geographical distribution of Subalpine Warbler Sylvia cantillans subspecies in mainland Italy MATTIA BRAMBILLA, 1 * GUIDO TELLINI FLORENZANO, 2 ALBERTO SORACE 3 & FRANCA GUIDALI 1 1 Universita degli Studi di Milano, Dipartimento di Biologia, Sezione Ecologia, Via Celoria 26, I-20133 Milano, Italy 2 DREAM Italia, via dei Guazzi 31, I-52013 Poppi (AR), Italy 3 Via R. Crippa 60, I-00125 Roma, Italy

Starting from a data‐set of 175 point counts (5 min duration) repeated twice a year from 1992 to 2002 in the Foreste Casentinesi National Park (Apennines, central Italy), the trends of species and of some selected ecological and phenological guilds were analysed. Among the 61 testable species, a significant increase (linear or quadratic regressions) involved 15 species, whereas 8 decreased. No significant trend was found for the remaining 38 species. The bark feeders guild, as well as tree‐cavity nesters and ground feeders showed an increase, whereas foliage feeders and ground nesters showed no significant changes. Short‐distance migrants and residents showed an increase, whereas long‐distance migrants showed no change. The overall picture obtained from these data fits well the habitat changes occurring in the study area: i) ageing of woods (with a remarkable increase in the proportion of mature stands in the study period); ii) afforestation of pastures and farmland, a long‐term process that star...

Ecological mathematical models are useful tools to define geographic distribution and ecological features of species, playing a fundamental role in defining conservation policies. Through the various methods we can use, recently, those which work with only-presence-data are growing in popularity and particularly MaxEnt. The recent colonization of Foreste Casentinesi National Park by Black Woodpecker represent a very interesting study-case to show how this method work, analysing possible evolution of an expansion process that is still evolving.