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aspects, they are similar in being forested Neotropical areas that share comparable faunas. 



The most frequently sighted taxa at Ejido X-Hazil y Anexos were the plain chachalaca (n = 64 

 sightings), squirrels (n = 47), kinkajou (n = 31), and coati (n = 17). Of these three, however, only 

 the coati and plain chachalaca were considered as game species by Maya hunters (see Chapter 3 for a 

 description of game species). 



At least three environmental variables may be responsible for the abundance of wildlife at 

 Neotropical forest sites (Emmons, 1984): soil type, undergrowth density, and rainfall and seasonality. 

 Neither undergrowth density nor rainfall and seasonality were analyzed with respect to wildlife densities 

 at Ejido X-Hazil y Anexos. Soil properties, however, were studied by Noguez-Galvez (1991) and can 

 help explain the low number of wildlife taxa in the study area as soils help determine the type of 

 vegetation that an area potentially can support. 



The soils at Ejido X-Hazil y Anexos, according to the FAO classification system, correspond 

 to the Order Rendzinas, Suborder Calcomorphics, while according to the USDA classification system, 

 these soils correspond to the Order Mollisols, Suborder RendoUs (United States Department of 

 Agriculture, 1960). At Ejido X-Hazil y Anexos, these soils have good structure; drainage; and a high 

 content of organic matter, calcium, carbonates, and bicarbonates (Noguez-Galvez, 1991). As a result 

 of a shortened fallow period, from 20 y previously to 10 y at present, however, soils at X-Hazil now 

 are nutrient-poor. Noguez-Galvez (1991) predicted that serious degradation of the soils and cover 

 vegetation will occur within a short period of time if tbis frequency of forest clearing continues. While 

 the length and severity of this nutrient deficiency problem are unknown, it is quite possible that the 

 soils and cover vegetation at the study area consequently are unable to support wildlife population 

 densities found elsewhere in the Neotropics. 



Soil fertility has been used to explain differences in animal biomass levels in Neotropical 

 forests in South America. Janzen (1974) proposed that animal biomass should be less on nutrient-poor 

 soils that produce black- water rivers in tropical forests than on soils that produce white- water rivers. 

 The mechanism predicted for this difference was the high level of toxic secondary chemicals in plant 



