The Fish Collection of Dubrovnik Natural History Museum has been put together ever since the founding of the museum in 1872. The periods in which the most additions were made were during the eras of Baldo Kosić, Milivoj Ulaga and Andrija Lesinger. Between 1882 and 1917 teacher, natural historian and taxidermist Baldo Kosić collected, determined and prepared an almost complete collection of fish of the Dubrovnik region. Unfortunately the wet part of the collection was destroyed during World War II, and part of the dermoplastic specimens deteriorated thanks to frequent moves, improper handling and inappropriate storage. After the death of Kosić, the Museum had no preparator until 1953, when Milivoj Ulaga arrived on the scene, and he, in collaboration with the Oceanographic Station – today the Marine and Coastal Institute, assembled a new collection of fish preserved wet and also made part of the still existing dermoplastic preparations. But after just a few years doing this job, Ulaga was transferred. Taxidermist Andrija Lesinger arrived in the Museum in 1960, and started on the lengthy process of restoring the old collection. He also collected new material and made about 170 preparations, which were on show until the earthquake of 1979 that closed the Museum. From 2011, new material has been collected.
The collection has been processed in its entirety, and the documentation has been kept in a computer database since 2013. Since 2015 it has been number 6590 in the Register of Cultural Properties of the Republic of Croatia.