Revista de Etologia
Print version ISSN 1517-2805
ALMEIDA, Marcos Vinícius de; PAULA, Hugo Medeiros Garrido de and TAVORA, Renata Souza. Observer effects on the behavior of non-habituated wild living marmosets (Callithrix jacchus). Rev. etol. [online]. 2006, vol.8, n.2, pp. 81-87. ISSN 1517-2805.
In order to assess the influence of the presence of a human observer on the behavior of wild, non-habituated common marmosets (Callithrix jacchus), a group of marmosets was exposed to sessions of observation in which observers were visible and in which they hided into a blind. Results indicated that typical defensive reactions such as alarm calls and stares at observers were reduced when observations were made from inside the blind. There was no significant differences in other parameters such as foraging/social contact calls, minimal distance from observer and time duration of sessions. Both major and minor modifications in normal behavior of free living animals may thus arise from the conditons of observation and should be taken into account.
Keywords : Defensive behavior; Observer effect; Blind; Observational methods; Callithrix jacchus; Comportamento defensivo; Efeito do observador; Barraca de observação; Callithrix jacchus.