Category: Alcidae

Can Norwegian and Russian Razorbills Alca torda be identified by their measurements

Razorbill (Alca torda) Science Article 4 abstract Razorbills Alca torda were measured in one Russian and five Norwegian colonies. A comparison with measurements from colonies in Britain, Ireland, Iceland and the Baltic Sea shows a clear correlation with the geographical position of each colony and a clinal increase in size from the south-west to north-east. […]

IMPACTS OF INTRASPECIFIC KLEPTOPARASITISM ANDDIET SHIFTS ON RAZORBILL ALCA TORDA PRODUCTIVITYAT THE GANNET ISLANDS, LABRADOR

Razorbill (Alca torda) Science Article 10 abstract Intraspecific kleptoparasitism, the stealing of food from members of the same species, has received widespread but mostly superficial attention in the scientific literature. However, the effects of such behavior can be significant. Here we report on high rates of intraspecific kleptoparasitism in the Razorbill Alca torda at the […]

Effects of island isolation and feral mink removal on bird communities (Alca torda) on small islands in the Baltic Sea

Razorbill (Alca torda) Science Article 7 abstract 1.) Predation has been suggested as a major cause affecting survival, reproductive success and behaviour in vertebrate prey populations. The breeding season is a critical phase because the essential difference between selecting the proper nest site may be a question of breeding success and failure. 2.) Islands may […]

Sex differences in razorbill Alca torda parent-offspring vocal recognition

Razorbill (Alca torda) Science Article 9 abstract We investigated differences in parent-offspring vocal recognition between males and females in a natural population of razorbills Alca torda, a long-lived and highly social species of auk (Family: Alcidae). Razorbills provide biparental care to their chicks while at the nest site, after which the male is the sole […]

Comparative foraging ecology of planktivorous auklets in relation to ocean physics and prey availability

Parakeet Auklet (aethia psittacula) Science Article 2 abstract tested the hypothesis that the spatial distributions of foraging least, crested and parakeet auklets (aethia pusilla, A. cristatella and A. psittacula, respectively) in the shallow passes of the Aleutian Islands would be determined by physical mechanisms that control near-surface prey concentrations. We recorded currents using an Acoustic […]