Bernt Wilhelm Westermann (sometimes Westerman), a wealthy Danish merchant and entomologist, was the son of Marcus Nissen Berentsen Westermann and his wife Wilhelmine Marcilia Christiane Wegener. He was a pupil of Johann Christian Fabricius (1745-1808), one of the chief founders of scientific entomology. In 1801 he travelled to the East Indies and collected insects in Bengal (eastern India, 1801-1811) and Java, Indonesia (1811-1816). In 1813, in Jakarta, he married Elisabeth Christina Frederika Schmidgall. On his way back to Europe he stayed at the Cape of Good Hope for some time during the summer of 1816/1817 and went on several excursions with the apothecary Carl H. Bergius* to collect insects. The results did not meet Westermann's expectations. He had been at the Cape before during the rainy season - presumably on the outward leg of his journey - and expected better collecting in the summer. During his second visit he applied for permission for himself and his servants to remain in the colony, but did not stay.

Westermann made a large collection of mainly tropical insects. After his return to Europe he expanded his collection through exchanges and corresponded with numerous European entomologists during 1828-1850. At his death the collection contained some 45 000 species, of which 31 000 were beetles. His specimens are now in the Zoological Museum in Copenhagen. In 1833 Westermann published a paper entitled "Ueber die Lebensweise der Insecten in Ostindien und am Cap" (On the habits of insects in the East Indies and at the Cape) in the Magazine der Entomologie, but a paper by him with the same title appears to have been published earlier in Germar's Magazine (1821). He does not appear to have published anything else. The moth genus Westermannia was named after him.

List of sources:

AGRIS: Food and Agriculture Organization of the United Nations. The entomologist B.W. Westermann... Retrieved on 3 May 2021 from https://agris.fao.org/agris-search/search.do?recordID=XE8021635

FamilySearch: Bernt Wilhelm Westermann. https://ancestors.familysearch.org/en/K24P-VJ3/bernt-wilhelm-westermann-1781-1868 AND https://www.familysearch.org/ark:/61903/1:1:6K53-BRLZ?lang=en

Ffolliott, P. & Liversidge, R. Carl Heinrich Bergius, Cape apothecary and collector, 1816-1818. Quarerly Bulletin of the South African Library, 1964, Vol. 18, pp. 134-142 and 183-192.

Google scholar. http://scholar.google.co.za/

National Automated Archival Information Retrieval System (NAAIRS). http://national.archives.gov.za/naairs.htm Documents relating to BW Westerman,

Royal Society of London. Catalogue of scientific papers [1800-1900]. London: Royal Society, 1867-1925.

Compiled by: C. Plug

Last updated: 2026-03-09 10:06:49