Salt extraction dominated a great deal of the economic activity during of the islands in the later part of the XIX century. This industry was in charge of a Dutch man Cornelius Boye also a naturalist who welcomed many other naturalists and scientists to Los Roques such as Adolph Ernst. He has provided not only scientific information but also vivid details of life in Gran Roque.
The extensive exploitation of wood timber from the mangrove was another activity developed in Los Roques during the XIX century. Although there are not written accounts of this, but steam ships stopped by frequently in search of timber for the boilers of steam ships. This stop in Los Roques was convenient as timber was abundant and cheap and sometimes free of charge. Great amounts of mangrove trees disappeared in the chimneys of many steam ships.
Very little is known about other two other activities carried out here: limestone production and the burning of vegetable coal. Both activities according to testimony by very old inhabitants were done by people from the Dutch island of Curacao and under extremely difficult conditions. The work of men between under the hot sun and the heat of limestone ovens was terrible. Coal and limestone production was distributed in the nearby Dutch islands and in the Venezuelan mainland.
All men who wandered by Los Roques from Amerindians to those who burnt coal and limestone collected salt, Botuto, captured turtles, lobsters, iguanas and birds and used wood from the mangrove tree for burning and construction also developed, and improved fishing constantly during the years. As a result over the centuries man has affected the resources and the landscape of the archipelago. The islands shaped man, society and its beliefs.