WTadeusz Chrostowski was a Polish naturalist and explorer who made three expeditions to collect natural history specimens, especially birds, in the Paraná region.
WJanusz Domaniewski (1891–1954) was a Polish ornithologist.
WAndrzej Stanisław Julian Dunajewski was a Polish zoologist and ornithologist.
WCount Włodzimierz Dzieduszycki was a Polish nobleman, sportsman and ornithologist. He was a member of the Polish Committee for War Victims at the end of World War I and during World War II he created an underground resistance force in Zarzecze to protect Polish refugees.
WKonstanty Roman Jelski was an acclaimed Polish ornithologist and zoologist who explored French Guiana.
WJohn Stanislaw Kubary, also stated as Jan Stanisław Kubary, Jan Kubary, or Johann Stanislaus Kubary, was a Polish naturalist and ethnographer.
WMaksymilian Siła-Nowicki was a Polish zoology professor and pioneer conservationist in Austrian Poland, and father of the poet Franciszek Nowicki. He was brother-in-law to Kraków University law professor and rector Franciszek Kasparek.
WJózef Siemiradzki was a Polish, geologist and naturalist and explorer. He was professor of paleontology at the University of Lviv (1901-1933). Siemiradzki studied nature at the University of Tartu. He visited Latin America three times: 1882–1883, 1892, and 1895.
WJan Bogumił Sokołowski was a Polish zoologist who worked as a professor at the University of Poznan who was a specialist in ornithology and studied the birds of Poland and made efforts for their conservation. He was also a talented artist and a writer of popular articles which included his own illustrations.
WJan Sztolcman was a Polish ornithologist.
WWładysław Taczanowski was a Polish zoologist and collector of natural history who explored the Russian Far East and northern Africa. He specialized mainly in ornithology but also described numerous other taxa including reptiles and arachnids.
WCount Konstanty Tyzenhauz was a Polish-Lithuanian nobleman, naturalist, artist, and sponsor of ornithology in Poland. He made a large collection of eggs and bird skins at his estate in Postawy.
WCount Kazimierz Antoni von Granöw Wodzicki was a Polish-born New Zealand mammalogist and ornithologist. He served as a Consul-General to the Polish government-in-exile in New Zealand towards the end of the Second World War and aided numerous Polish refugees to settle there.