- The following article is copyright 1997 African Technology Forum. All rights reserved. Preserving the Future for Lake Malawi Joshua Nyambose* Overfishing and increased economic activity are depleting the fish stock in Lake Malawi, Africa's third largest lake. Between 1988 and 1992, the commercial fish catch fell by over 20 percent. This problem has major economic and environmental consequences ...web.mit.edu/africantech/www/articles/Lake_Malawi.html