Busu is a tiny, man-made, island in the Langa Langa Lagoon in Malaita Province of the Solomon Islands. The artificial islands of the lagoon have been built up on sand bars over time by a population, supposedly, fleeing the mainland. I guess the population is around 200 and you can walk around the island in 10 minutes.
The islanders are basically subsistence fishermen and farmers (with families having gardens on small plots of land on the mainland, some 1 km away). Fishing and the production of shell necklaces (for marriage ceremonies) are the main, if not only, sources of income.
