Although the killing of giant tortoises in the Galapagos Islands hasbeen prohibited since 1933, poaching of tortoises still occurs.Personnel of the Galapagos National Park Service and the CharlesDarwin Research Station regularly survey populations of tortoisesthroughout the archipelago and report all dead tortoises found. Forthe 10-year period 1995–2004 the field personnel reported evidenceof 190 giant tortoises killed, primarily on the southern portion ofIsabela Island. For the first 6 years the number of tortoises foundkilled was <15 per year, but since 2001 the number killed hasincreased dramatically, with 49 tortoises poached in 2004. Duringthe same 10 years the number of tortoises found dead from naturalcauses was 131. Many of these deaths can be attributed to eventsassociated with the 1997–1998 El Niño or with outbreaks of diseaseon Santa Cruz Island in 1996 and 1999. The results indicate thatpoaching exceeds natural mortality, and is a significant factoraffecting these long-lived and slow-reproducing animals.Environmental education efforts in the human population of southernIsabela appear to have had little effect. Because tortoise poachingtakes place at a small number of sites, effective enforcement atthose sites could reduce killing of tortoises.