Stray dogs may serve as sentinels of environmental exposure to bacterial taxa of veter-inary and zoonotic relevance, particularly in areas with intense hu-man—animal—environment interactions. In this study, whole-blood DNA from 72 stray dogs sampled in tourist beach sites of Michoacán, Mexico, was analyzed by 16S rRNA gene amplicon sequencing targeting the V3–V4 region. To assess variation among those sites, samples were pooled by location, and bacterial composition and diversity were compared among beach zones. A broad diversity of circulating bacterial DNA was de-tected, comprising 14 phyla, 87 orders, 186 families, and 462 genera based on data-base-supported classification. Several assignments corresponded to genera that include bacteria of veterinary and zoonotic relevance, such as Brucella, Clostridium, Mycobacte-rium, Rickettsia, and Mycoplasma, as well as taxa commonly associated with opportunistic pathogenicity. However, because 16S rRNA sequencing has limited taxonomic resolution and blood is a low-biomass sample type, these findings should be interpreted as taxo-nomic assignments of circulating bacterial DNA rather than evidence of viable bacteria or active infection. Differences among beach zones suggest that local environmental con-ditions may influence detected profiles. Overall, this exploratory study supports the potential of stray dogs as indicators of environmental microbial exposure in coastal Mexico.