The ability of infection-causing bacteria to develop resistance to the antibiotics used to treat them (called Anti-Microbial Resistance or AMR) is a worldwide threat to human and animal health. Harbor seals are sentinels of ocean health, and we will study AMR in very young harbor seals in a wildlife hospital. Using genetic sequencing, we will identify genes that code for resistance, and evaluate how the resistance genes in individual seals change during their treatment.