Dunckerocampus baldwini is found in caves, rocky crevices, and the seaward slopes of coral reefs and it is an active cleaner which has been recorded gleaning small parasitic crustaceans on cave cardinal fish (Zapogon evermanni) and a moray eel (Gymnothorax sp.). It has also been reported associating with iridescent cardinalfish (Pristiapogon kallopterus) and Hawaiian squirrelfish (Sargocentron xantherythrum) It is an ovoviviparous species, in which the males brood fertilised eggs in a pouch beneath their trunk before giving live birth. The brood size can be as large as 200 embryos. They reach a maximum size of 15 centimetres (5.9 in), and males begin brooding at 10.7 centimetres (4.2 in). It has been recorded from Hawaii, and was thought to be endemic to that archipelago, it has since been recorded in West Papua and off Christmas Island but which island this refers to is uncertain, as there is an island, Kiritimati, sometimes called Christmas Island in Kiribati, as well as one in the eastern Indian Ocean.
- Clay-Smith, S. & Pollom, R. (2016). "Dunckerocampus baldwini (errata version published in 2017)". The IUCN Red List of Threatened Species. 2016: e.T65366377A115420376. doi:10.2305/IUCN.UK.2016-3.RLTS.T65366377A67624125.en.
- Froese, Rainer and Pauly, Daniel, eds. (2018). "Dunckerocampus baldwini" in FishBase. February 2018 version.
- Bruce Carl Mundy (2005). Checklist of the Fishes of the Hawaiian Archipelago. Bishop Museum Press. p. 318. ISBN 978-1-58178-044-4.