Results 51 to 60 of about 709 (138)

Trophic discrimination of amino acid ‐specific nitrogen stable isotopes in raptor nestlings: implications for estimating trophic position

Journal of Zoology, Volume 327, Issue 3, Page 236-247, November 2025.
We used high‐precision diet estimates from nest cameras to estimate amino acid‐specific trophic discrimination factors (TDFs) for gyrfalcon nestlings and compared these against TDFs for other taxa from the literature. TDFs for trophic amino acids in gyrfalcon were lower than values that have typically been used to estimate trophic position.
A. Bautista, D. L. Johnson, M. T. Henderson, D. L. Anderson, T. L. Booms, C. T. Williams   +5 more
wiley   +1 more source

Absence of negative effect of GPS‐tags on survival and breeding success in a long‐lived territorial raptor

Ibis, Volume 167, Issue 4, Page 1053-1064, October 2025.
GPS tracking has enabled significant advances in the study of animal movements such as migration and habitat use. However, GPS devices can affect the behaviour of tagged individuals, especially for flying animals such as birds, and may ultimately impair their reproduction and/or survival.
Lise Viollat, Roger Pradel, Cécile Ponchon, Alain Ravayrol, Alexandre Millon, Aurélien Besnard   +5 more
wiley   +1 more source

Avian influenza overview June–September 2025

EFSA Journal, Volume 23, Issue 10, October 2025.
Abstract Between 7 June and 5 September 2025, 183 highly pathogenic avian influenza (HPAI) A(H5) virus detections were reported in domestic (27) and wild (156) birds across 15 countries in Europe. Although HPAI A(H5N1) virus detections were predominant in western and southwestern Europe, they also occurred on the northernmost coast of Norway. More than
European Food Safety Authority, European Centre for Disease Prevention and Control, European Union Reference Laboratory for Avian Influenza, Leonidas Alexakis, Hubert Buczkowski, Mariette Ducatez, Alice Fusaro, Jose L. Gonzales, Thijs Kuiken, Gražina Mirinavičiūtė, Karl Ståhl, Christoph Staubach, Olov Svartström, Calogero Terregino, Katriina Willgert, Miguel Melo, Lisa Kohnle   +16 more
wiley   +1 more source

Effect of local prey availability on gyrfalcon diet : DNA analysis on ptarmigan remains at nest sites

, 2006
The aim of this study was to investigate how the diet of gyrfalcon Falco rusticolus in northern Sweden was affected by the relative availability of its two main prey species: rock ptarmigan Lagopus mutus and willow ptarmigan Lagopus lagopus.
Nyström, Jesper,, Ekenstedt, Johan, Angerbjörn, Anders,, Angleby, Helen, Dalén, Love,   +4 more
core   +1 more source

Bone Mineral Density of Willow Ptarmigan (Lagopus lagopus) as a Potential Taphonomic Factor in Skeletal Part Attrition

International Journal of Osteoarchaeology, Volume 35, Issue 5, Page 284-294, September/October 2025.
ABSTRACT Agents of taphonomy can bias skeletal parts and the frequency of bones in archaeological sites. An important factor to consider is the possible effect of bone density‐mediated attrition on archaeornithological assemblages. We scanned willow ptarmigan (Lagopus lagopus) specimens using a Lunar iDXA and an enCcore small animal body add‐on to ...
Frank J. Dirrigl Jr., Samuel R. Buchanan   +1 more
wiley   +1 more source

Genetic diversity assessment and individual identification of gyrfalcon (Falco rusticolus) in Iceland

, 2011
Verkefnið er lokaðThe Icelandic gyrfalcon (Falco rusticolus) is a small and isolated non-migratory population and its ecological status has been carefully monitored for the last three decades.
Lára Guðmundsdóttir
core   +1 more source

Climatic variation affects seasonal survival of an alpine bird species

Wildlife Biology, Volume 2025, Issue 4, July 2025.
Mountains are particularly exposed to climate change, and empirical studies have shown that montane bird species are highly sensitive to the ongoing changes. Modelling mortality risks under climatic variation will give insight into species‐specific sensitivity. Willow ptarmigan Lagopus l.
Lasse Frost Eriksen, Thor Harald Ringsby, Markus F. Israelsen, Pål F. Moa, Vidar Grøtan, Erlend B. Nilsen   +5 more
wiley   +1 more source

First record of gyrfalcon Falco rusticolus in Korea

, 2010
On 20 March 2010, One Gyrfalcon (Falco rusticolus) was observed at Nakdong river, Sangju city, Gyeongsangbukdo province (E128° 14′ 25.6″ N36° 25′ 05.0″), and this is the first record of this species for the Korean peninsula. The Gyrfalcon has distributed
I H Paik, C Y Park, W K Paik, S D Jin, W H Hur, J P Yu, S H Kim, Jeong Ran Han, H J Kim, J H Kim   +9 more
core  

The overwhelming influence of ptarmigan abundance on gyrfalcon reproductive success in the central Yukon, Canada [PDF]

, 2011
Companion studies of Willow Ptarmigan (Lagopus lagopus) and Gyrfalcons (Falco rusticolus) in the central Yukon from 1978 to 1983 allowed us to examine Gyrfalcon reproductive performance at 14 nest sites in relation to ptarmigan abundance and other ...

core  

Avian influenza overview March–June 2025

EFSA Journal, Volume 23, Issue 7, July 2025.
Abstract Between 8 March and 6 June 2025, 365 highly pathogenic avian influenza (HPAI) A(H5) virus detections were reported in domestic (167) and wild (198) birds across 24 countries in Europe. HPAI A(H5N1) virus detections were predominant and mainly located in western, central and south‐eastern Europe.
European Food Safety Authority, European Centre for Disease Prevention and Control, European Union Reference Laboratory for Avian Influenza, Leonidas Alexakis, Hubert Buczkowski, Mariette Ducatez, Alice Fusaro, Jose L. Gonzales, Thijs Kuiken, Gražina Mirinavičiūtė, Karl Ståhl, Christoph Staubach, Olov Svartström, Calogero Terregino, Katriina Willgert, Miguel Melo, Lisa Kohnle   +16 more
wiley   +1 more source