We sampled the respiratory mucus from voluntary blowhole exhalations of three healthy beluga whales (Delphinapterus leucas) under professional human care. Blow samples were collected from three resident belugas, one adult male (M1) and two adult females (F1, F2), with voluntary behaviors via non-invasive methods over three days in July 2021 (four days for M1). DNA was extracted from samples and used for 16S rRNA and 18S rRNA (anti-metazoan) microbiome sequencing. Water from the habitat was also collected and sequenced.