The Ikpikpuk River Delta on Alaska’s Arctic Coastal Plain is experiencing rapid landscape change driven by the interacting effects of increased coastal flooding, permafrost thaw, and ecological disturbance from a rapidly expanding Lesser Snow Goose population. Hydrological monitoring from 2011 to 2022 reveals a marked increase in flood frequency and duration, particularly in the period following spring freshet. At a tundra-mounted pressure transducer located 1 km inland, inundation occurred for parts of 24 days prior to 2015, increasing to 51 days between 2015 and 2018, and exceeding 80 days in 2019 and 2021. GPS surveys indicate ~0.2 m of land surface subsidence between 2013 and 2021, likely exacerbating flood exposure. Rising salinities in inland lakes and ponds—such as one site where average salinity rose from 0.6 to 2.9 ppt—indicate storm surges and coastal inundation are expanding inland. Simultaneously, Lesser Snow Geese have become a dominant biotic driver of change, with nest counts increasing from fewer than 1,000 in the early 2000s to over 14,000 by 2021. Through grubbing and trampling, the geese remove vegetation, expose soils, and may promote permafrost degradation. Remote sensing reveals extensive landcover shifts, highlighting a delta in rapid transition shaped by climatic, geomorphic, and ecological forces.