Blue-green algae blooms have reappeared in various locations, posing significant health risks to humans and animals. In Lough Neagh, Northern Ireland, the algae has reached 2023 levels, causing visible green mats and foul odors, with potential to impact the Bann river and the north coast. Similar blooms have closed Yates Park beach in Orchard Park, New York, and prompted warnings around Mashapaug Pond and Blackamore Pond in Rhode Island, where all recreational activities are advised against. In Denver, Colorado, Sloan’s Lake has seen a massive fish die-off linked to algae blooms and high summer temperatures. These incidents highlight the widespread environmental and public health concerns associated with blue-green algae proliferation.