He eventually became curator of the Zoological Museum in Buitenzorg. As such he received a photo and a skin of a Komodo dragon from Lieutenant Jacques Karel Henri van Steyn van Hensbroek who had been the first Westerner to observe the lizards and had been told that they could reach 6 to 7 meters. Ouwens dispatched a collector to Komodo who returned to Java with two adults and a young specimen. Ouwens named the species Varanus komodoensis in a publication of 1912. Ouwens became Officer of the Order of Orange-Nassau and died in Buitenzorg in 1922.