Red mangroves were first brought to Hawai’i from the Philippines in the early 1900s. Today the park service fights a hard battle to pull them out. Mangrove roots smother out native Hawaiian plants and fill coastal environments with anoxic (lacking oxygen) sediment that destroys wetlands crucial to native species of plants and birds.
The first time I saw a seed, I was swimming and it startled me. They float vertically and nose to nose in the waves I thought it was an eel or something. Ha! This is the first sprouted one I’ve ever found. You can see those determined roots starting out at the bottom there. Good in Florida, bad in Hawai‘i.