In Nigeria's Lagos, aquatic weed plagues waterways EWNLAGOS ? Traffic jams on the snarled up roads of Nigeria's megacity of Lagos are legendary, but a growing problem is also clogging up the waterways of Africa's biggest city - water hyacinths. The spread of the invasive species of fast-growing plant is not only damaging transport links in Nigeria's economic capital, built on a lagoon dotted with islands. With waterways covered and silting up, the aquatic weed is also threatening fishing jobs and a vital food source. "This is all I can get since morning," said fisherman Solomon Omoyajowo, showing a handful of fish in a bowl in his wooden canoe...