‘Detection of stress levels in Alouatta palliata mexicana in fragmented habitat’

Alba Gómara Castaño, Alberto Conde Flores, Carlos Enrique Riba Campos, David Roberto Chavira Ramírez, Domingo Canales Espinosa, Ernesto Rodríguez Luna, Francisco García Orduña, Joaquín José Veà Baró, Jordi Sabater Pi, Jurgi Cristóbal Azkarate, Lara Carrasco Pesquera, Lourdes Boeck Quirasco, Montserrat Colell Mimó, Samuel K. Wasser, Sira Vegas Carrillo, Sònia Sánchez López.

For the purpose of the study, we will develop a methodology to discriminate between different stress sources, based on an analysis of three indicators – cortisol, thyroid hormone (TH) and immunoglobulins (IG) – in the faeces of Mexican mantled howler monkeys (Alouatta palliata mexicana), a subspecies in critical danger of extinction due to habitat loss and fragmentation. Specifically, we will examine the levels of cortisol, TH and IG in the faeces of four troops of howlers living in four forest fragments of markedly differing ecological density in the Los Tuxtlas Biosphere Reserve, Mexico.

We will next check these levels against (1) seasonal changes in food availability between and within groups (2) seasonal changes in bot fly parasitation rates, and (3) changes in group social dynamics. The application of this methodology will allow us to rapidly evaluate the state of A. palliata populations and identify the origin of the stress detected in them.