Two mortality events in a colony of Tarāpuka (black-billed gulls, Chroicocephalus bulleri), an 'at risk-declining' and endemic species in Aotearoa occurred in 2023 and 2024. In a colony of 500 adult and 200 juvenile birds, nesting near the Māngere Bridge in Auckland, an estimated 160 juveniles died within a period of a few days. A collaborative effort from various wildlife agencies across Aotearoa identified the disease agent as a schistosome trematode, Austrobilharzia terrigalensis. In this kōrero (talk), I'll chat about what we know about this parasite, how it got to New Zealand, into our gulls and what it means for their conservation and the surrounding ecosystem.