Antimicrobial resistance in Galapagos tortoises as an indicator of the growing human footprint

Antimicrobial resistance has become one of the main public health threats worldwide with anthropogenic activities driving spread resistance. Understanding and combatting resistant bacteria is a top priority for global institutions, it included as goals One Health initiative. Giant tortoises ( Chelonoidis spp.), some most iconic species on Earth, are widely distributed across Galapagos archipelago thus perfect candidates to test hypothesis that wildlife in carry antimicrobial genes (ARGs) associated human activities. We sampled total 200 free-living from western Santa Cruz Island C. porteri ), human-populated island archipelago, 70 vandenburghi ) isolated Alcedo Volcano Isabela Island, natural area minimal presence. Fecal samples were analyzed by quantitative PCR panel 21 ARGs conferring eight classes. found both giant tortoises; however, qualitative results showed higher loads inhabiting modified environments Cruz. Moreover, human-modified landscapes (i.e., farmlands urban areas) presented number ARGs, classes, multi-resistant microbiomes than those less anthropized areas within same island. Our findings suggest have negative impact ecosystem through ARG dispersal. This research highlights new threat conservation unique Galapagos, their ecosystems, humans this World Heritage Site. recommendation local policy makers control reduce use antibiotics animal health, helping enforce regulations. • Anthropogenic levels prevalence Galapagos. Island. may act good sentinels health. tortoises.