Air pollution from metallurgical plants is a problem in Macedonia, as in the other former Yugoslav republics. In 1996, industrial carbon dioxide emissions totaled 12.7 million metric tons. All urban dwellers have access to safe drinking water. Earthquakes are a natural hazard. Forest and woodland cover 30% of the nation's land area. As of 2001, approximately 7.1% of Macedonia's total land area was protected, including one World Heritage Site and one Wetland of International Importance. As of 2001, the list of threatened species included 10 types of mammals and 3 types of bird. Endangered species include the field adder, Apollo butterfly, and noble crayfish.