The California least tern (Sternula antillarum browni, CLT) is an endangered migratory seabird that nests in managed nesting colonies, predominantly in San Diego County, California. In collaboration with Harris & Associates, and the 22nd District Agricultural Association, the San Diego Natural History Museum has been monitoring nesting terns at San Dieguito Lagoon since 2023, where two colonies were first established in 2020. For five years, the colonies have sustained a relatively small but increasing number of adults that successfully fledge young, and reproduction has appeared resilient to regional stressors; site use has more than doubled from 15 nesting attempts in 2020 to 37 in 2025. Since our monitoring began, fledgling success has grown from just 10-14 to 32-34 young fledged from 2023 to 2024, and preliminary data from 2025 suggest the site was again largely successful. This resilience may be attributable to our intensive monitoring and predator management approach and to the geography of the sites. Given the inherent stochasticity of CLT management, the increasing success at these sites despite downward statewide trends offers a valuable case study that sparks conversations on management practices, geographic considerations for newly established tern sites, and hope for the species’ recovery.