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In many migratory birds, males precede females during migration and arrival at the breeding sites. Three proximate mechanisms are proposed to explain this phenomenon of protandry: males 1) winter closer to breeding sites, 2) start spring migration earlier, and/or 3) migrate faster than females. So far, the relative contribution of these mechanisms to protandry is unknown. The present study investi
Brent Geese migrating in spring towards Arctic Canada have been tracked by satellite from Iceland to the Davis Strait. Length and direction of the stages were adapted to the geographic features and hospitability of the areas crossed; the ice-cap of Greenland was overflown in its southern part.
The orientation of four species of passerine long-distance migrants was studied in spring and autumn by orientation cage experiments during the twilight period after sunset in Sweden. Two groups of migrants from the Palaearctic-African migration system were used: migrants wintering mainly north of the magnetic equator in west Africa (pied flycatcher, Ficedula hypoleuca, and redstart, Phoenicurus p
Background: The motivation of birds to proceed with migration is associated with both endogenous and exogenous factors. According to their migratory situation and to the characteristics of stopover sites, birds might exhibit migratory motivation differently among sites. Although migratory motivation of migrating birds has been well stud-ied in many species, the investigation of the same species in
Ringing recoveries from 18 different passerine species captured at an inland ringing site in south Sweden (Kvismare Bird Observatory) were analysed with respect to direction and distance of migration in order to investigate the occurrence of temporary reverse movements opposite to the expected forward migratory direction towards south and south-west in autumn. The data demonstrate that movements i
The biometrics, age ratio and timing of migration of Robins were compared during autumn migration at an inland and a coastal site 200 km apart. The proportion of adult birds was higher at the inland site. The time of peak of migration differed between the two sites by 9 days. The daily distribution showed that at the coastal site the birds made a land‐fall at dawn, while at the inland site the mig
A migratory divide is a narrow region in which two populations showing different migratory directions meet and presumably also mate and hybridize. Banding of willow warblers, Phylloscopus trochilus, in Europe has demonstrated a migratory divide latitudinally across central Scandinavia. In autumn, southern birds migrate southwest to tropical West Africa, whereas northern birds migrate southeast to
Bodypainting is widespread in African, Australian and Papua New Guinean indigenous communities. Many bodypaintings use white or bright yellow/grey/beige stripes on brown skin. Where the majority of people using bodypainting presently live, blood-sucking horseflies are abundant, and they frequently attack the naked brown regions of the human body surface with the risk of transmitting the pathogens
The orientation of four different species of nocturnal passerine migrants was investigated in spring and autumn by orientation‐cage experiments at dusk, night, and dawn under natural clear skies. Our objective was to examine the orientation behaviour at different periods of a nocturnal migration flight, and to relate the orientation to visual orientation cues (the position of the sun). In robins,
Birds have evolved a mobile lifestyle in which vision is of major importance when controlling movements, avoiding predators, finding food and selecting mates. Birds have extraordinary colour vision and have been suggested to perceive the linear polarisation of light. Behavioural experiments support this idea, but still the exact physiological mechanism involved is not known. The twilight period, w
Absolute environmental sustainability assessments quantify the environmental impacts of human activities in relation to ecological carrying capacities. Such assessments necessitate the application of sharing principles to allocate shares of carrying capacity to actors and activities at different scales, including products, companies, sectors, and countries. This can help decision-makers set target
With simultaneous policy and scholarly attention to the pollution crisis and the climate crisis, there is growing recognition that the two are intimately interconnected through the demand for oil, gas, and coal generated by synthetic materials. Drawing on theoretical resources from international political economy and beyond, we show how petrochemicals sit at the intersection of a number of the pri
Vårdvalet blev obligatorisk inom den svenska primärvården år 2010, vilket utökade patienternas valmöjligheter och gjorde det möjligt för privata vårdgivare att etablera sig med offentlig finansiering. Även om vårdvalsreformens påverkan på primärvårdens utformning är allmänt erkänd, är resultaten gällande dess effekter på jämlikhet i vårdutnyttjande delvis motsägelsefulla.Det överordnade syftet med
Phosphorus (P) is a critical macronutrient for plant growth, often limiting plant production in areas where plant demand is higher than soil supply. In contrast to nitrogen (N), P cannot be sourced from the atmosphere; therefore, where it is rare, it becomes a strong constraint on primary production. Due to this, most dynamic global vegetation models (DGVMs) are incorporating a prognostic P cycle
