Antibiotic resistance is a rapidly accelerating epidemic demanding novel approaches. Gastropod mucus has been shown to possess antimicrobial properties and could potentially be used as an ingredient in antibiotic development. However, whether the mucus of Ariolimax columbianus, the banana slug, also displays antimicrobial properties is unknown. In this study, we investigated whether the mucus of A. columbianus is resistant to Escherichia coli (E.coli), Streptococcus aureus (S.aureus), and Klebsiella pneumoniae (K.pneumoniae), three medically relevant strains of bacteria. Specimens were collected from a coniferous forest and isolated for downstream mucus extraction. We spread uniform concentrations of our bacteria on Mueller-Hinton agar plates and subjected them to a Kirby-Bauer disc diffusion test by treating them with either discs dipped in mucus or discs dipped in mucus and HBSS. Zones of inhibition did not form on the plates after subjecting the bacteria to either treatment. While this study was limited to a few taxa and one experimental approach, our study suggests that gastropod mucus may not have a generalized scope of antimicrobial activity. Rather, antimicrobial activity of mucus may be more specific to taxa encountered by the slugs in their redwood forest habitat. Our results can be used to refine mucus extraction methods for A. columbianus in future studies that seek to investigate the potential of mucus for biotechnological applications