Diagnosing in-flight adjustment to wind by birds is challenging, since they may follow landmarks, take detours, soar in thermals or become wind drifted. Gulls are noted opportunists and flight generalists...
Body temperature is a key physiological property of any animals, and its measurement is thus a valuable tool in ecological and physiological studies. In birds, variation in body temperaturer has been related to a range of parameters...
Surviving in cold environments at high latitudes puts a great premium on behavioral, morphological and physiological adaptations to conserve heat. One of the most prominent adaptations is the plumage of birds which when fluffed may form...
Understanding the population ecology of different phases in the complex annual cycle of long-distance migratory birds, and determining the importance of winter vs summer vs migration impacts, and their carry-over effects, on population dynamics...
Like the rainbow shimmer on a soap bubble, the blue color of this male tree swallow (Tachycineta bicolor) feather is iridescent. Light reaching the feather is reflected by its microstructure like a myriad of small mirrors, making it look very bright...
When I signed up to move to Kaua‘i and began an M.Sc. project studying the nesting biology of two recently-listed endangered forest bird species, the ‘Akikiki and ‘Akeke‘e, I knew I was in for a rewarding challenge!
Ever since I first visited Ammarnäs in Swedish Lapland in 2007, Red-necked Phalaropes captured my special interest. Well-known for their reversed sex roles, their pelagic lifestyle outside the breeding period has hampered the study of their non-breeding biology...
Breeding is obviously a very important part in the life of organisms. However, the effort put into breeding need to be traded off against effort put into defense of the parents’ own soma. One often neglected part of parental effort is to protect young...
It is common that avian scientists working with breeding biology claim that weather has a large impact on breeding productivity although this is usually just a “feeling” and seldom formerly tested.
New tracking techniques have opened up possibilities to record individuals on repeated foraging flights and investigate to what degree they show individuality in their behaviour.
This study compares annual survival patterns of red knots Calidris canutus islandica between two periods, when winter food at the Wadden Sea was reduced by cockle harvesting and in following years when cockle-dredging was stopped...
The start of breeding during a season has generally a large impact on reproductive success in passerines. Given the importance of this trait, we know astonishingly little about what factors determine the start of breeding in individual birds...
During the spring of 2012, Gabriella Jukkala was just about to graduate from Northland College. After extensive discussions, Gabby and I became interested in how adult loons might protect their chicks during their fragile first weeks of life...
Food resources are generally patchily distributed which has triggered a plethora of foraging models predicting both exploration behaviours to find high-quality patches and exploitation levels when foraging in a patch...
For a long time, I’ve been fascinated by the variation in breeding systems, morphology, habitats and other general lifestyles of waders. When I first learnt about light-level geolocation as a technique for tracking the non-breeding movements...
A phylogenetic analysis of auks, puffins and their allies including both extant (23) and extinct (28) alcid species gives new and fascinating pespectives about the possible origins and diversification as well as about the reconstruction of ancestral diet...
The adaptive variation in avian body composition has for a long time been interesting from an energy turn-over point of view. Besides being inferred as the basis of variation in basal metabolic rate, such variation is also important for generating work as for example...
With a little bit of ‘basic math’, Russian biologist Eldar Rakhimberdiev shows how changes in seasonal survival may be used as a tool to detect problems in bird populations. ‘A dip in survival during a certain period or in a certain place, means the population...
Increased perceived predation risk during breeding is predicted to reduce parental effort as such behaviours often are conspicuous and are traded off against vigilance...
A male ruby-throated hummingbird approaches an artificial feeder outfitted with a passive-integrated transponder reader and a precision electronic balance. As this bird perches to feed its ID is detected and its mass is automatically recorded.
