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The great reed warbler Acrocephalus arundinaceus is a common migrant through the Western Palearctic. However, its migration strategy, especially the spatiotemporal pattern of accumulation and utilisation of energy stores en route, is poorly known. Using ringing data collected at distant stopover sites located from Central Europe to Asia Minor, we observed that pattern in juvenile great reed warblers migrating along the eastern European flyway in autumn. We analysed body condition and stopover duration and estimated potential flight ranges for this species, taking into account two large ecological barriers – the Mediterranean Sea and the Sahara Desert – which it crosses during its southward migration. In Central and South-Eastern Europe the seasonal trends in body condition were similar and non-linear, with low values in August (i.e., during intensive migration of Acrocephalidae), and then a significant increase from the beginning of September until the end of the month. Estimated potential flight ranges showed that individuals migrating through Central and South-Eastern Europe might generally reach only the northern coast of the Mediterranean Sea. On the other hand, those flying from Asia Minor were able to reach the northern edge of the Sahel zone, crossing two large ecological barriers without refuelling. Therefore, it seems that great reed warblers change their autumn strategy en route: first, they migrate in short steps with low energy reserves through continental Europe; and then, after intensive refuelling before the Mediterranean Sea, they reach sub-Saharan Africa in a long flight. Based on the analysis of ringing data from several stopover sites, we show the complex pattern of how a long-distance migratory species accumulates and utilises its energy stores en route.

In contrast to the rapidly growing body of knowledge on migratory routes, wintering grounds and timing of annual life cycle events of migratory birds, knowledge on how migratory songbirds refuel at stopover sites along the Asian–Australasian flyway has increased only slowly, despite the fact that migrant birds show declining trends along it. We analysed the amount and variation of energy stores between species, variation of energy stores within the day and within the season, and estimated flight ranges of ten closely related warbler species (genera Acrocephalus, Arundinax, Locustella and Phylloscopus), captured at a stopover site in the Russian Far East during the autumn migration. We found significant differences in the species’ energy stores, with Pallas’s Leaf Warbler Phylloscopus proregulus having by far the highest. All species increased their energy stores within the day, and eight species increased their energy stores within the season. Individuals with the highest estimated flight ranges were able to cover a distance of 470 km during one nocturnal flight bout, which would have resulted in a minimum of nine stopovers before the birds reached their wintering grounds. We assume that a combination of factors determines the variation in energy stores between these species. We discuss the potential for these birds to exploit different habitats and refuelling strategies according to the distribution of species-specific refuelling habitats, and a variety of food resources, along the migratory route. This study is the first to provide information on energy stores, refuelling strategies and flight ranges for a set of closely related songbird species migrating along the Asian–Australasian flyway.

The efficacy of natural enemies in controlling pests under field conditions is largely correlated with their capacity to spread within infested crops. In this study the spatial dispersal of the California red scale parasitoid Aphytis melinus DeBach (Hymenoptera: Aphelinidae) was evaluated in the field after augmentative releases. The experiment was conducted in 2007 in six 1-ha plots in a Sicilian citrus orchard under integrated pest management. A total of 180,000 A. melinus adults was released in each of three plots and the other plots were left as untreated control. The flight range of the parasitoid was evaluated, for 35 days after the release, on 16 trees per each plot, located at 20 and 40 m from the central release point using yellow sticky traps activated with Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) sexual pheromone and by monitoring the percentage parasitism of the scale on fruits and twigs. The effects of the distance from the release point and density of susceptible stages of host on parasitoid dispersal were evaluated. The number of wasps captured during the whole trial was greater in the traps located 20 m from the release point than in those at 40 m and in the control plots. Aphytis melinus dispersed over distances less than 40 m based on both the lower per- centage parasitism and numbers captured recorded at distances of 40 m. The results are discussed in the context of the biological control of California red scale in citrus orchards by means of wasp releases. In particular, the release points should be no more than 40 m apart for a quick and homogeneous colonization of the area treated.

The northern coast of Pernambuco State, Brazil, is an wintering area for shorebirds originally from north America, especially from the east. The first flocks arrive in September, staying till April, when they molts, change plumage, and acquire enough biomass to migrate back to the northern hemisfere. In order to calculate flight range mass and length of the wing of Charadrius semipalmatus Bonaparte, 1825, Calidris fuscicollis Vieillot, 1819, C. pusilla Linnaeus, 1766 and C. alba Pallas, 1764 was recorded. Traps were carried out in Coroa do Avião (7º40' S and 34º50'W) in the northern coast of the State of Pernambuco, between May 1992 and April 1995. The length of the wing was registered with the wing spread (from the insertion of the bone till the extremity of the longest primary remige). Individuals which were changing the tenth primary were not included in this measuring. Mass was taken in grarns, and flight range was calculated using the equations proposed for adult individuais. The individual with the highest flight range reached around 1831,87 km, and had been trapped and ringed in 14th April 1994, when had 61,5 g and wing measuring 12,9 cm, with intermediate plumage. The highest flight range reached by C. fuscicollis was around 1906,43 km. It had been trapped and ringed in the 3rd of May 1992, with weight of 50 g, and wing of 12,9 cm, and had reproduction plumage. The individual with the highest flight range reached 3545,77 km, had been trapped and ringed in 15th April 1994, weighted 44 g, wing measured 10 cm, and presented intermediate plumage. The specimen of C. alba which presented the highest flight range, of 82 g, wing of 13,4 cm, and had intennediate plumage.

The distance a bee can fly to collect food is quite relevant, among other aspects, for successful pollination. However, studies on this aspect concerning stingless bees usually do not take into consideration their homing ability. The objectives of this study were to verify the maximum distance that foragers of Melipona mandacaia Smith can fly, and whether experience is relevant for their homing ability in a Caatinga region of Northeast Brazil. Five colonies were used to collect foragers. These were marked and released starting from 100 m from their nests and at every 100 m up to a maximum distance on which there would be no bee returning to the nest. To evaluate the influence of experience, after being marked, another group of bees was put back into colonies, collected again after eight days and released in five distances only (500, 1,000, 1,500, 2,000 and 2,500 m). In both experiments, as the distance increased, the returning success of the bees decreased significantly. In fact, there was a significant negative correlation between their returning success and the distances they were released. The maximum distance a translocate bee returned to its hive was 2,700 m. The percentage of success was very high for bees released at 500 and 1,000 m (100% and 77%, respectively), suggesting this is the common flight range for the species. In most cases, average percentage of success was significantly higher for experienced bees than for other bees reinforcing the idea that experience is quite relevant for homing ability.

Short-tailed shearwaters Puffinus tenuirostris migrate annually from breeding areas in southeast Australia and Tasmania to the Bering Sea to feed on abundant prey aggregations, mainly euphausiids. Occasionally thousands of shearwaters die of starvation en route, within, or on return from the Bering Sea. Collection of live and dead shearwaters in the southeastern Bering Sea in 1997, 1998, and 1999 allowed us to measure seasonal changes in energy reserves during a major mortality event. As birds lost body mass, lipid mass initially decreased faster than that of pectoralis muscle, but loss of pectoralis mass increased markedly at a body mass around 500 g when lipids were almost depleted (~33 g remaining). Death occurred as body mass approached 426 g. Individuals near this body mass had lipid values permitting estimated flight ranges of 140 to 400 km, a range less than that potentially covered in 1 d by shearwaters searching for prey (440 to 1124 km d -1 ). Seasonal differ- ences in body composition were most striking among body and bone marrow lipid contents, with the lowest values occurring during the die-off in fall 1997 and in fall 1998. The lack of shearwater mor- tality in fall 1998 may have resulted from more consistent winds that decreased flight costs and from greater availability of alternative fish prey. Our data allow estimates of usable energy stores and flight ranges based on lipid reserves in short-tailed shearwaters. Estimated flight ranges suggest that if feeding conditions are poor near Japan or near other termination points of the transequatorial migration routes shearwaters may have few reserves available to support foraging for food and star- vation events may occur. Our findings suggest how their energetic strategies and migration are shaped by seasonal and annual variability of prey during transglobal movements of short-tailed shearwaters between oceanic regions.

We documented fat loads and abdominal organ sizes of Bar-tailed Godwits (Limosa lapponica baueri) that died after colliding against a radar dome on the Alaska Peninsula, most likely just after takeoff on a trans-Pacific flight of 11,000 km, and of birds of the same subspecies just before northward departure from New Zealand. We compared these data with data on body composition of godwits of the smaller lapponica subspecies obtained during a northward stopover in The Netherlands. As a consequence of high amounts of subcutaneous and intraperitoneal fat, and very small fat-free mass, Bar-tailed Godwits from Alaska had relative fat loads that are among the highest ever recorded in birds (ca, 55% of fresh body mass). Compared with northbound godwits from New Zealand, the Alaskan birds had very small gizzards, livers, kidneys, and guts. This suggests that upon departure, long-distance migrants dispense with parts of their "metabolic machinery" that are not directly necessary during flight. and rebuild these organs upon arrival at the migratory destination.

We report the results of three mark-release-recapture experiments carried out in an urban area in Rome, Italy, to study the active dispersal of Aedes albopictus (Diptera: Culicidae). The 4.3% recapture rate obtained supports the use of sticky traps in MRR experiments to study the dispersal of Ae. albopictus females. Most fluorescent dust-marked females were recaptured at the gravid stage at 50-200 m from the release sites during the first 9 days after release. The average of daily-MDTs (Mean Distance Traveled) was 119 m and the maximum observed distance travelled ranged from 199 m to 290 m in the three replicates. These data provide the first information about the dispersal of Ae. albopictus in a temperate European area and appear to be consistent with the few data available on this subject from other urban areas, where dispersal was constrained by physical barriers. Although caution should be taken in generalizing these results, they should be considered when planning control activities in urban areas in Italy, as well as in other European countries. This is particularly relevant if control is intended to interrupt pathogen transmission in cases of possible arbovirus epidemics, such as the Chikungunya outbreak that occurred in Ravenna, Italy in 2007.