this is like my favourite image of the whole trip

Fish Poison Tree (Barringtonia asiatica)

The fish poison tree is native to tropical mangrove habitats across the Indian Ocean and western Pacific Ocean. As its name suggests, all parts of the tree are poisonous. In some cultures, the seeds of the tree are ground up and used to incapacitate or kill fish for easy capture

 The active poisons, including saponins, are soluble and form a foamy sud when agitated in water. The fish take in the poison directly into their blood stream via the gills, which acts on the respiratory organs of the fish. This does not affect their edibility. The fish float to the surface where they are easily collected by fishermen. 

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