Birds performing long-distance migration without substantial refuelling en route rely on fat reserves accumulated in the post-breeding, pre-migratory period. In order to fill a knowledge gap in the pre-migratory behaviour of purple herons Ardea purpurea, a species conducting a 3,500–4,000 km migration journey within 5–7 days, 12 adult and four juvenile purple herons were equipped with satellite transmitters in The Netherlands. The birds were followed during and after the breeding period until they departed for their migration. Based on the recorded positions, the location and the size of pre-migratory feeding areas were identified, as well as the duration herons used these sites. In addition, the location of and the distance flown to and from night roosts could also be defined. The results revealed that failed breeders started migration at the same time as successful breeders resulting in a longer pre-migratory period. After fledging, juveniles showed an initial “search period” before settling down at a final pre-migratory site, which resulted in later departure to Africa compared with adults. Most of the dusk- and daylight period (amounting altogether to 15–18 hours) was spent at the feeding sites. After breeding, most adults remained to use the same feeding areas but switched from sleeping in the colony to night roosts within feeding areas, likely to minimize the daily flight costs. Based on the daily foraging time, the pre-migratory period seems to be sufficient to deposit reserves for a migration journey of several thousand kilometres. Above this, our results generally highlight the importance of high-quality pre-migratory feeding areas for long-distance migrants without extensive stop-over periods.

Space-use strategies are essential behavioural skills during the fledging-to-dispersal period, when physical capabilities and the ability to explore the external world are developed. Here we describe the space-use strategies of 13 radio-tagged ospreys Pandion haliaetus, released as part of a reintroduction project in Central Italy, during their post-fledging dependence period. The ospreys remained within a radius of about 1 km of the hacking tower for about twenty days after release. Later they began to explore more of their surroundings. The occurrence and frequency of explorations further than 1 km from the release point generally increased with time, even though juveniles continued to frequent the vicinity of the release pens. The translocated ospreys showed marked aggregation perhaps because the period spent at the hacking tower could have reinforced the feeling of belonging to the same brood, promoting a consequent strong association among the young. Also, the absence of parents may have led juveniles to aggregate as a compensation behaviour for the lack of parental care. These explanations, which are not mutually exclusive, may have resulted in more time being spent in intraspecific interactions, accounting for the long pre-dispersal phase that we observed in the present study.

We update and present relevant information regarding the abundance and distribution of the great bustard Otis tarda in Castilla y León (Spain) in 2008, compare it with previous census results, and analyse the effects of agricultural changes on the provincial abundance and distribution of the species. The study area was surveyed from four-wheel drive vehicles driven at low speed (20–30 km/h) along predetermined transects, stopping frequently at prominent spots. The intention was to detect all the great bustards present in the study area. The great bustard population in Castilla y León during the breeding season of 2008 was 14,025 birds: 5,637 males, 7,760 females and 628 individuals whose sex could not be determined. The population was 34% greater in 2008 than in 1998 when the area surveyed in both censuses is compared. Population increases were recorded in all provinces except for Soria, where no birds were observed. Not all local populations within provinces increased: we detected population declines of over 10% in 43 (27%) of the 160 polygons surveyed both in 1998 and 2008, population increases of over 10% in 93 (58%) polygons, and largely stable populations (changes less than 10%) in 24 (15%) polygons. Provincial increases in bustard numbers were positively correlated with increases in the extent of unirrigated legume crops. The great bustard population in Castilla y León in 2008 was the largest in the world, accounting for 27–32% of the global population and about 47% of the estimated Spanish population. The spread of unirrigated legumes, crops that are promoted by agrienvironment schemes, may have fostered the observed population increase between 1998 and 2008. A survey of the region every ten years is proposed to monitor future population trends.

The population size of the Pyrenean population of the bearded vulture Gypaetus barbatus, the most important viable wild population in Europe, remains poorly known, despite its status as endangered in Europe. In this study, the abundance of immature vultures and adults (both territorial and floaters) was estimated in the Aragón region, the core area of the Pyrenean population, to provide an indicator of the total Pyrenean population. Using artificial feeding stations specifically designed for bearded vultures as survey points, 25 censuses were conducted during March 2010 in which 873 sightings (106 of individually marked birds and 767 of unmarked birds) were recorded. By applying the mark-recapture method, the total population of bearded vultures in the study area during the winter period was estimated to be 328 individuals (95% CI: 279–391 individuals). Separate estimates by age groups suggested a population of 129 immature individuals (95% CI: 107–160) and 227 adults (95% CI: 173–311). The adult floating population was estimated at 49 individuals and the adult non-breeding fraction was 93 individuals. Compared to previous censuses, the results suggest that although the reproductive fraction is increasing, the total population still has some problems: the immature fraction is not increasing, as predicted in previous studies, and a high proportion of adults are not contributing effectively to the breeding process. Conservation measures should focus on these two issues to increase the viability of the Pyrenean population.

Wildfires are certainly a key natural disturbance to terrestrial Mediterranean ecosystems. After an intense fire different types of habitats revert to relatively similar open hábitats. This early successional stage has been shown to be used by many open-habitat bird species, which are able to colonise these new suitable habitats. By adopting a regional scale perspective, we assessed to what extent post-fire colonisation by open-habitat birds is constrained by the degree of isolation of burnt areas or the size of the burnt patch, and analysed the influence of the period elapsed since a fire on species colonisation. We focused on the Catalan population of the ortolan bunting Emberiza hortulana and estimated the amount of dispersal flux into a number of recently burnt areas as a measure of patch isolation, using regional data derived from atlas surveys and connectivity metrics based on graph theory. Our results show that species occurrence on recently burnt areas was primarily driven by the amount of dispersal flux, and to a lesser extent by the extent of the burnt area. Species occurrence also tended to increase with time since fire, suggesting that effective colonisation was partly driven by stochastic ecological and behavioural processes. We suggest that the prediction of species' responses to disturbances on large spatial scales should explicitly integrate not only species' responses to habitat changes but also information on dispersal constraints imposed by species' ecology.

The use of biometrics in studies of migratory connectivity is still relatively infrequent in Europe. This is partly due to the fact that biometrics is a less accurate tool when compared to ringing recovery data, or such techniques as stable isotope analyses, use of geolocators or satellite telemetry. Combination with one of these (recovery data) allows us to test the usefulness of biometrics in connectivity analyses, as well as to evaluate/quantify the influence of migratory behaviour on phenotypic traits such as flight morphology. We used historical recovery data, together with flight morphology data obtained from a consistent collection protocol during a three-year ringing programme carried out at seven sites in Spain (within the eastern half of Iberia), to test the usefulness of flight morphology for analysing spatio-temporal distribution patterns of migrants at a population scale. Blackcaps Sylvia atricapilla were used as our avian model. Two hypotheses were tested: (1) whether migrant blackcaps use the shortest flyways between their breeding and non-breeding areas, so that blackcaps entering Iberia through more eastern flyways come from breeding regions further east, and (2) whether the species is a leap-frogging migrant, in which populations from more northerly regions overwinter further south than those of more southerly origin. Blackcaps entering Spain through the western Pyrenean flyway (WF) had more westerly origins than those entering through the eastern Pyrenean flyway (EF). Blackcaps captured in the WF had more rounded and shorter wings as well as relatively longer tails than those from the EF, indicating a more marked long-distance migration morphology in the EF. However, blackcaps from the EF did not come from more distant regions, so flight morphology was not linked to distance travelled from the region of origin. The fact that both recovery data and biometrics differed between flyways suggests that here flight morphology is an adequate tool with which to study population-associated connectivity patterns. No evidence of leap-frog migration was detected in the study area where biometric data were obtained.

Los Padres, La Brava and Nahuel Rucá lakes are typical wetlands of the Pampean region. These three shallow lakes share certain limnological features (size, mean depth, littoral macrophytes, among others) and the land usage in their basins (e.g. agriculture, cattle ranching and/or touristic activities). We surveyed the bird community at these three wetlands over three years (May 2006-May 2009), using transects and point counts to characterise their species richness, abundance, community composition and seasonality. We recorded a total of 135 species belonging to 41 families. The Relative Importance Index showed that the neotropic cormorant Phalacrocorax olivaceus, the cattle egret Bubulcus ibis, the white-tufted grebe Rollandia rolland and the white-faced ibis Plegadis chihi are the most representative species. Species richness, species composition and abundance differed between wetlands. Such differences could be attributed to particular factors such as proximity to urban centres or other wetlands, and to the impact of recreational activities. Considering that the Pampean region is currently under strong anthropogenic impacts, the present study contributes to the improvement of management plans that are currently in place or under development.

Although widespread in Europe, the white-throated dipper Cinclus cinclus has a fragmented distribution in the Iberian Peninsula. We investigated whether Iberian dipper populations are genetically differentiable by assessing a fragment of the cytochrome b gene in birds from 11 geographical areas encompassing 48 Iberian rivers. Four population groups North, Centre, East and South were differentiated a priori on the basis of geographical criteria. Genetic differences between these groups explained 35.9% of the total variation. Eight new haplotypes have been recorded for this species. The most abundant haplotype (H3) was shared by 75.8% of the birds and was found in all areas. The second most abundant haplotype (H10, 17.6% of individuals) was present in three areas: two in the southern mountains and one in central Iberia. The third most abundant (H5, 4.8% of birds) occurred only in central Iberia. Southern populations are genetically distinct from the others.

This paper explores the changes in the number of diurnal migratory birds crossing the Strait of Gibraltar between 1977 and 2008, to test whether the numbers of birds wintering in the Maghreb have decreased over the last 30 years. Results show that the most abundant species in 1977 were the most abundant ones in 2008. However, they also showed a decrease in the relative contribution of partial migrant species. A similar analysis of data from the Falsterbo Observatory (Sweden) did not reveal any decreasing contribution of partial migrants to the flux of migrant birds moving from northern Scandinavia.

In order to provide an insight into the genetic differentiation between the four currently recognised subspecies of the common crane Grus grus, we sequenced the mitochondrial control region of a total of eight birds. Genetic distances ranged from 0.3–1.1%, hardly supporting the distinction of the morphologically defined subspecies. A Neighbor-net and a BioNeighbor-joining tree, however, did recover shallow phylogenetic structure largely in accordance with taxonomy. Therefore, the genetic diversity must be fairly young and morphological differences seem to have evolved rapidly. In addition to more comprehensive sampling, analyses of microsatellite loci or single nucleotide polymorphisms may be necessary to assess the degree of genetic cohesion within and between groups of populations and putative subspecies of the common crane.

Ringing of yellow-legged gulls Larus michahellis michahellis begun in Algeria in 2009, the first scheme of its kind in North Africa. Ringing of chicks was initiated at Skikda and extended a year later to four other colonies located along the Algerian coast. Preliminary analysis of observations of ringed yellow-legged gulls from Algerian colonies indicates that juveniles dispersed in a northwesterly direction to the Balearic Sea and the Bay of Biscay, and westwards to the Alborán Sea and the Iberian Atlantic coast from Cadiz Bay to Galicia. Preliminary results suggested two distinct routes: gulls from the eastern Algerian colonies moved N/NW to eastern Spain and overland to the Bay of Biscay, a pattern of dispersal previously reported for birds from Spanish and French western Mediterranean colonies. Juveniles from western colonies seemed to move N/NW to the Alborán Sea and Cádiz Bay. In Spain, to where most dispersal occurred, the data suggests that Algerian gulls summered at coastal areas before returning to North Africa in late autumn and winter.

A survey was conducted on Madeira Island (Portugal) from 9 May to 2 June 2008 to determine population size and distribution of the common buzzard Buteo buteo. Distance sampling on foot was carried out along 87.6 km of transects. The species was present in small numbers in all areas sampled. Population size was estimated at 409 (95% CI 275–608) individuals at a density of 0.55 buzzards/km² (95% CI 0.37–0.83), based on 39 observations. The present survey sets a baseline for future studies monitoring changes in the common buzzard population on Madeira.