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Moult-related reduction of aerobic scope in passerine birds

It is well established that the nutrient and energy requirements of birds increase substantially during moult, but it is not known if these increased demands affect their aerobic capacity. We quantified the absolute aerobic scope of house and Spanish sparrows, Passer domesticus and P. hispaniolensis, respectively, before and during sequential stages of their moult period. The absolute aerobic scop

A full annual perspective on sex-biased migration timing in long-distance migratory birds

In many taxa, the most common form of sex-biased migration timing is protandry—the earlier arrival of males at breeding areas. Here we test this concept across the annual cycle of long-distance migratory birds. Using more than 350 migration tracks of small-bodied trans-Saharan migrants, we quantify differences in male and female migration schedules and test for proximate determinants of sex-specif

Migration, wing morphometry and wing moult in Spanish and House Sparrows from the eastern Balkan Peninsula

On the Balkan Peninsula, migratory Spanish Sparrows breed sympatrically with resident House Sparrows. While the two species share many biological and ecological traits, migratory patterns and adaptions to migratory lifestyle of the Spanish Sparrow are unknown. We tracked a Spanish Sparrow across its 1800 km long migration from Bulgaria to the nonbreeding sites in the Nile Delta. Stopovers were sit

Miniaturized multi-sensor loggers provide new insight into year-round flight behaviour of small trans-Sahara avian migrants

Background: Over the past decade, the miniaturisation of animal borne tags such as geolocators and GPS-transmitters has revolutionized our knowledge of the whereabouts of migratory species. Novel light-weight multi-sensor loggers (1.4g), which harbour sensors for measuring ambient light intensity, atmospheric pressure, temperature and acceleration, were fixed to two long-distance migrant bird spec

Spatiotemporal Group Dynamics in a Long-Distance Migratory Bird

Thousands of species migrate [1]. Though we have some understanding of where and when they travel, we still have very little insight into who migrates with whom and for how long. Group formation is pivotal in allowing individuals to interact, transfer information, and adapt to changing conditions [2]. Yet it is remarkably difficult to infer group membership in migrating animals without being able

Host migration strategy and blood parasite infections of three sparrow species sympatrically breeding in Southeast Europe

Mobile hosts like birds occupy a wide array of habitats in which they encounter various vector and parasite faunas. If the infection probability for vector-borne parasites varies among seasons and biomes, a migratory life can critically influence the infections of a host. The growing body of literature on avian blood parasites suggests that host migrations do not only influence prevalence of infec

Blood parasites prevalence of migrating passerines increases over the spring passage period

Whether long-distance animal migration facilitates or hampers pathogen transmission depends on how infections affect the routes and timing of migrating hosts. If an infection directly or indirectly impedes migratory flight capacity, infected individuals lag behind their uninfected conspecifics. Although such temporal segregation can limit parasite transmission and thus play an important role for h

Low intensity blood parasite infections do not reduce the aerobic performance of migratory birds

Blood parasites (Haemosporidia) are thought to impair the flight performance of infected animals, and therefore, infected birds are expected to differ from their non-infected counterparts in migratory capacity. Since haemosporidians invade host erythrocytes, it is commonly assumed that infected individuals will have compromised aerobic capacity, but this has not been examined in free-living birds.

Intra-tropical movements as a beneficial strategy for Palearctic migratory birds

Migratory birds often move significantly within their nonbreeding range before returning to breed. It remains unresolved under which circumstances individuals relocate, whether movement patterns are consistent between populations and to what degree the individuals benefit from the intra-tropical movement (ITM). We tracked adult great reed warblers Acrocephalus arundinaceus from a central and a sou

Shifts in vegetation phenology along flyways entail varying risks of mistiming in a migratory songbird

Long-term shifts in vegetation phenology generally follow the pattern of global warming. Yet, topographical complexity and biome diversity cause uneven spatial trends in the phenological response of vegetation to climate change. If phenology changes similarly along migration routes, individuals may adequately respond by shifting the whole migration schedule to still time life history with local ph

Barrier crossing in small avian migrants : Individual tracking reveals prolonged nocturnal flights into the day as a common migratory strategy

Over decades it has been unclear how individual migratory songbirds cross large ecological barriers such as seas or deserts. By deploying light-level geolocators on four songbird species weighing only about 12 g, we found that these otherwise mainly nocturnal migrants seem to regularly extend their nocturnal flights into the day when crossing the Sahara Desert and the Mediterranean Sea. The propor

Longer wings for faster springs - wing length relates to spring phenology in a long-distance migrant across its range

In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate-driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at loc

A pan-European, multipopulation assessment of migratory connectivity in a near-threatened migrant bird

Aim: The extent to which individuals from different breeding populations mix throughout the non-breeding season (i.e. 'migratory connectivity') has important consequences for population dynamics and conservation. Given recent declines of long-distance migrant birds, multipopulation tracking studies are crucial in order to assess the strength of migratory connectivity and to identify key sites en r

Variable detours in long-distance migration across ecological barriers and their relation to habitat availability at ground

Migration detours, the spatial deviation from the shortest route, are a widespread phenomenon in migratory species, especially if barriers must be crossed. Moving longer distances causes additional efforts in energy and time, and to be adaptive, this should be counterbalanced by favorable condition en route. We compared migration patterns of nightingales that travelled along different flyways from

Individual migration timing of common nightingales is tuned with vegetation and prey phenology at breeding sites

Background: The timing of migration substantially influences individual fitness. To match peak requirements with peak resource availability, we hypothesized that individual migrants schedule spring migration in close relation to seasonal changes in environmental conditions along the route and particularly, at the breeding destination.To test this hypothesis, we investigated the timing of spring mi

Directional shifts in migration pattern of rollers (Coracias garrulus) from a western European population

Individual migrants often fly detours when travelling between breeding and non-breeding sites, resulting in specific changes in flight directions along a migratory leg. Western European populations of the European Roller (Coracias garrulus), the only member of the roller family of birds to breed in Europe, differ substantially in their predicted flight directions, leading to different hypotheses b

Decreased excretion of glycosaminoglycans in patients with primary glomerular diseases

Urine glycosaminoglycans (GAG) concentrations were measured in 150 patients with primary glomerulonephritides: endocapillary glomerulonephritis, mesangial proliferative glomerulonephritis, IgA nephropathy, membranous glomerulonephritis and minimal change nephropathy, and in 63 healthy controls and 19 patients with diabetes nephropathy. The urine GAG to creatinine ratios (GCR) were significantly re

Decreased excretion of urine glycosaminoglycans as marker in renal amyloidosis

BACKGROUND: The diagnosis of renal amyloidosis is normally established by kidney biopsy. In order to advance the determination of the diagnosis and the initiation of the therapy, fast and cheap, non-invasive diagnostic techniques are required.METHODS: Urine excretion of glycosaminoglycans (GAG) was measured in 10 patients with AA amyloidosis and 5 patients with AL amyloidosis and compared to 25 co