A map of merchant ships sunk by U-Boats from U-Boat.net shows an area with an unusually high occurrence of U-Boat victims offshore from where the Orinoco River meets the Atlantic Ocean in a region of marshy tributaries, mangrove swamps, and low-lying savannah grasslands called llanos. Referred to as the Orinoco Delta, the area is bordered on the south by the Guyana Highlands, and on the west by the higher ground of the Orinoco River valley. The Delta was a sparsely populated area in the 1940’s and remains so today, inhabited by the indigenous Warao people. Oil was discovered in the Delta in 1890, and exploration for new field intensified in the 1940s, driven by the wartime need for increased production. However, the crude oil found in the Delta is thick, viscous and difficult to produce, and production from this area was minimal during the war. There was not a large fleet of tankers carrying crude oil from the Orinoco River to northern refineries during WWII.
At first glance, one might wonder why the U-Boats found it worthwhile to expend boats, crews, and torpedoes in such a remote area. The answer lies in a combination of geology, climate, and the Allies need for a critical raw material. While the U-Boats along the Venezuelan coast further to the northwest primarily targeted oil tankers carrying crude oil from Lake Maracaibo, the sinkings off the Orinoco Delta were merchant freighters carrying aluminum ore from the port city of Georgetown. The ore consists of a mineral called bauxite, which is found in the former British colony of British Guinea, now called Guyana.
Located immediately to the south of the Orinoco Delta, Guyana is a country with intense tropical rainfall, approaching 90 inches per year. Falling on tropical rainforests and filtering through the soil down to ancient rocks that form what geologists call the Guyana Shield, the precipitation dissolves most of the elements in the rocks, such as sodium, potassium, and silicon. The rocks also contain abundant aluminum, which is very insoluble in water, and the weathering process leaves behind aluminum ore in the form of the mineral bauxite. Due to this combination of climate and geology, Guyana is the second largest producer of bauxite in the world today and was a vital supplier to the Allies during WWII. Bauxite is converted to aluminum metal in refineries through a complex chemical process, which supplies the material needed for aluminum aircraft components. The tremendous WWII increase in the manufacture of military aircraft in the US would have been impossible without a continuous supply of the raw material from Guyana.
During the war (and continuing today), bauxite from the mines in Guyana was loaded onto ships in the port of Georgetown, which then carried the ore to aluminum refineries in the United States. The German U-Boat command put a priority on stopping the shipments, well aware that a shortage of bauxite would cause a direct impact on the number of new warplanes being delivered to Europe. The bauxite freighters left the port of Georgetown and cruised north along the coastline of South America, offshore from the numerous branches of the Orinoco River emptying into the Atlantic Ocean. Knowing the route that the ships were taking and able to intercept them close to the origination point of their voyages, the U-Boats waited east of the Orinoco Delta for the freighters to arrive. Between 1942 and 1943, 40 ships were sunk off the Orinoco Delta and the coast of British Guinea. Thirty-seven were merchant aluminum ore.
The Orinoco Delta is the setting for my newest novel, The Orinoco Uranium, to be published in April 2023.