Visible at the bottom left of this image is Lake Maracaibo, in Venezuela, connected to the Gulf of Venezuela via the 55 km long Tablazo Strait. Some green swirls of color on the lake are due to the growth of duckweed, a problem plaguing the lake since the early 2000s. At times, over 18% of the lake has been covered by duckweed, and although efforts to remove the plant have been underway, the plant – which can double its size every 48 hours – occupies over 130 million cubic metres of the lake.
The only way to remove the weed is to pull it out of the lake physically – no chemical or biological method has been found to treat the weed. The government has been spending $2 million monthly to clean the lake, and the state-run oil company Petroleos de Venezuela S.A. has created a $750 million cleanup fund. Current efforts are barely keeping up with the growth of the plant. The removal process has proven to be particularly difficult in the center of the lake where a specially equipped ship may be needed to pull the weed off the lake.