1865 in birding and ornithology

• Birds described in 1865 include volcano hummingbird, white-fronted tit, Monteiro's hornbill, biscutate swift, bare-cheeked babbler, rufous-throated flycatcher, chestnut-rumped thornbill
• Osbert Salvin Descriptions of Seventeen New Species of Birds from Costa Rica.Proceedings of the Zoological Society of London 1864
• Death of German explorer Karl Klaus von der Decken.
• Death of Thomas Bellerby Wilson
• Death of Alfred Malherbe
• 1865 heralds rapid expansion of the collections of Cambridge University Museum of Zoology.
• Description of the fossil swan Cygnus falconeri.^[1]

Expeditions

• 1865–1868 Magenta circumnavigation of the globe Italian expedition that made important scientific observations in South America.
• 1865– HMS Curacoa
• Alfred Grandidier makes his first visit to Madagascar.

Ongoing events

• John Gould The birds of Australia Supplement 1851–69. 1 vol. 81 plates; Artists: J. Gould and H. C. Richter; Lithographer: H. C. Richter
• John Gould The birds of Asia 1850-83 7 vols. 530 plates, Artists: J. Gould, H. C. Richter, W. Hart and J. Wolf; Lithographers:H. C. Richter and W. Hart
• The Ibis