■ Geographic variation in body size of Black-headed Gull Chroicocephalus ridibundus
https://t.co/omAE9MiCjw
一つ目は、ヨーロッパ~カムチャツカ半島までのユリカモメ繁殖地にて、体サイズの地理変異をまとめたもの。
共同研究者の有馬さんがサンクトペテルブルクの博物館を訪れて標本を計測
Copperback Quail-thrush inhabits from WA to western SA. Split from Chestnut QT, no overlap in distribution ranges. It features a brighter, more extensive copper back. While usually seen walking in open woodlands, this time one was singing from a tree. South Australia, Jan 2026.
Nullarbor Quail-thrush: its range is restricted to the Nullarbor Plain. Similar to Cinnamon QT, but has an upside-down "T" shape where black throat meets breast band. After constantly hiding behind the shrubs, finally showed up right in front of me. South Australia, Jan 2026.