Driven by climate change, mangroves are migrating northward along the U.S. East Coast—expanding far beyond their traditional tropical range in southern Florida. Warmer winters and fewer frost events have enabled these salt-tolerant trees to establish themselves as far north as southern Georgia. In Jacksonville, Florida, average winter temperatures have risen by 3.4°F over the past five decades, providing ideal conditions for mangrove growth. This shift marks a dramatic transformation in coastal ecosystems, offering a real-time glimpse into how rising global temperatures are redrawing ecological boundaries.
While mangroves offer critical benefits—such as coastal protection, storm resilience, and carbon sequestration (they store up to four times more carbon per hectare than tropical rainforests)—their spread into traditional salt marshes also poses challenges. Native grasses and wildlife that depend on these marshes may be displaced, impacting local biodiversity, fisheries, and food webs. Scientists are calling for increased research and adaptive conservation efforts to understand and manage the long-term ecological impacts of this migration as climate change continues to reshape coastal landscapes. More