Turtles and their eggs have long served as an important source of food for humans—almost certainly since very early in the evolution of the hominid lineage, and surely for at least the last 20,000 years (Nicholls, 1977). Evidence in the form of shells and skeletal material (some showing burn marks as evidence of cooking) in the middens of Paleolithic aboriginal cultures, and from eyewitness accounts of explorer-naturalists in more recent times is available from numerous locations around the world (e.g., Bates, 1863; St. Cricq, 1874; Goode, 1967; Rhodin, 1992, 1995; Pritchard, 1994; Lee, 1996; Stiner et al., 1999). Skeletal evidence of river turtles, in particular from such locations as Mohenjodaro and Harappa in the Indus Valley (e.g., Indian narrow-headed softshells and river terrapins), Mayapan, and many other Mesoamerican Mayan sites (e.g., Central American river turtles), and Naga ed-Der of Upper Ancient Egypt (e.g., Nile softshell) suggest that river turtles have helped to support the rise of the world's great civilizations as well (de Treville, 1975; Nath, 1959 in Groombridge & Wright, 1982; Das, 1991; Lee, 1996). Their role continues and, in fact, has expanded as human populations have burgeoned and spread throughout the modern world. River turtles have always been too convenient and succulent a source of protein to ignore. Often large, fecund, and easily collected with simple techniques and equipment, especially in communal nesters which may concentrate at nesting sites in helpless thousands (at least formerly), river turtles are ideal prey. Much of the harvesting has been, and continues to be, conducted in relative obscurity in many parts of the world. Occasionally, however, the sheer magnitude of the resource and its slaughter has attracted the attention of literate observers, such as the early explorer-naturalists of the New and Old World tropics. Their accounts have given us some idea of the former truly spectacular abundance of some riverine species, and the equally spectacular levels of consistent exploitation which have brought them to their modern, much-diminished condition. Summaries of the exploitation of the two best documented examples of destruction of formerly abundant riverine species, the Asian river terrapin, and the giant South American river turtle, are provided under their appropriate geographic sections below.
Overcoming Information Limitations for the Prescription of an Environmental Flow Regime for a Central American River
