Department of Biological Sciences, University of Florida, Gainesville, FL 32611, UNITED STATES OF AMERICA.
Natural licks are particular sites in some types of habitats often visited by a number of wild animals with the purpose of licking or consuming soil (a behavior known as geophagy). Several studies associate geophagy with the nutritional ecology and/or health of the animals that use them. Therefore, the existence of natural licks in a particular habitat may reduce the costs of obtaining adequate nutrition, and/or maintaining health; and thus may be fundamental to population persistence. One of the habitats where natural licks exist is the Amazon forest. Many Amazonian wildlife species, including large birds and herbivorous mammals, are users of natural licks. Natural licks also may be important for rural communities that rely on wildlife for their subsistence. This is particularly important for Amazonian human communities, because one of the most common hunting techniques in those forests is waiting for game animals at natural licks.
Our study addressed the importance of natural licks for both wildlife and humans in the Yavari-Miri River valley in the northeastern Peruvian Amazon. A relatively large group of mammalian and large bird species frequently visited natural licks during 2001. The most frequent lick visitors were lowland tapirs. Natural licks found in the Yavari- Miri River valley had higher concentration of several minerals (Na, Ca, Mg, P, Cu, S, and B) compared to non-lick samples. Those differences were constant throughout the year; suggesting that natural licks are in fact, a source of minerals for wildlife in the Yavari- Miri River valley. The diet of the most-frequent lick visitor (the lowland tapir) was examined for mineral content. Results showed that combined foods eaten by lowland tapirs are of good quality regarding mineral content, except for Na, P, Cu and Zn. We suggest that tapirs supplement their mineral intake by consuming mineral-rich soils at natural licks in the Yavari-Miri River valley. The above results suggest that natural licks are a key resources for several Amazonian species because they represent a natural mineral source in the humid forest of western Amazonia.
To assess the importance of natural licks for Amazonian human communities, subsistence-hunting patterns were examined at the Nueva Esperanza village, in the Yavari-Miri River valley. Over 30% of total biomass hunted during 2001 was harvested at licks, and was heavily represented by lowland tapirs. Hunters of Nueva Esperanza village use more than 40 natural licks located along the Esperanza Creek and the middle and lower Yavari-Miri River. We recommend regulation of hunting at licks by temporal rotation of use. Also, we suggest that natural licks should be an attribute of habitat quality when selecting areas for wildlife conservation in western Amazonia.