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Providing evidence to improve practice

Individual study: Primates Living Outside Protected Habitats Are More Stressed: The Case of Black Howler Monkeys in the Yucatán Peninsula

Published source details

Rangel-Negrín A., Coyohua-Fuentes A., Chavira R., Canales-Espinosa D. & Dias P.A.D. (2014) Primates Living Outside Protected Habitats Are More Stressed: The Case of Black Howler Monkeys in the Yucatán Peninsula. PLoS ONE, 9, e112329


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Legally protect primate habitat Primate Conservation

A controlled, site comparison study in 2006-2007 in tropical forest in Campeche State, Mexico found that stress levels of black howler monkeys Alouatta pigra that lived in protected areas were lower than of those living in highly fragmented and unprotected forest patches. Overall mean stress levels, measured by faecal glucocorticoid metabolite (FGM), of individuals living in unprotected habitats were about 20% higher (338.9 ng/g) than those of individuals living in protected habitats (266.2 ng/g). However, agonistic interactions among group members occurred at similar frequencies during sampling weeks in both habitats (protected: 57.1%, unprotected: 62%). Furthermore, seasonal variation in FGM concentrations was only detected in protected habitats. The results of this study were based on 371 faecal samples from 21 adults belonging to five groups, two from protected habitats and three from unprotected habitats. FGM concentrations were determined with radioimmunoassays and 1,200 h of agonistic within-group and between-group interactions were recorded in total.