As an ornithologist, he was known for his study of bird behaviour and his intensive study of the Wren (Troglodytes troglodytes).
Christopher Wren | Eurasian Sparrowhawk | Eurasian Avars | Wren | Wren's Nest | Eurasian Collared Dove | Eurasian Hobby | Eurasian Bullfinch | John Wren | Eurasian lynx | Eurasian Dotterel | Eurasian beaver | Wren and Gurney | Taiwan Wren-babbler | Inca Wren | Eurasian Wren | Eurasian Wigeon | Eurasian Tree Sparrow | Eurasian Three-toed Woodpecker | Eurasian Penduline Tit | Eurasian Natural Resources Corporation | Eurasian Magpie | Eurasian brown bear | Canyon Wren | Amy Wren | Wren (Royal Navy) | Wren Library | Requiem for a Wren | Nepal Wren-babbler | Musician Wren |
The Daito Wren (Troglodytes troglodytes orii) is a controversial subspecies of the Eurasian Wren.