Abnormal behaviors in nursery-reared squirrel monkeys (Saimiri sciureus).

Area of Science:

• Primate behavior
• Animal psychology
• Developmental ethology

Background:

• Squirrel monkeys (Saimiri sciureus) are common subjects in research.
• Early life experiences significantly influence primate behavioral development.
• Understanding rearing effects is vital for animal welfare and research integrity.

Purpose of the Study:

• To investigate the behavioral impact of nursery rearing versus mother rearing in squirrel monkeys.
• To identify specific deviant behaviors associated with early developmental deprivation.
• To compare behavioral outcomes between nursery-reared and mother-reared Saimiri sciureus.

Main Methods:

• Comparative behavioral observation of 17 squirrel monkeys (11 nursery-reared, 6 mother-reared).
• Two observation periods at approximately 6.7 and 15.5 months of age.
• Categorization of observed behaviors, focusing on nonnutritive orality, stereotypic posturing, and agitation.

Main Results:

• Thirteen distinct deviant behaviors were observed exclusively in nursery-reared squirrel monkeys.
• No such behaviors were recorded in mother-reared subjects.
• No significant differences in behavior were linked to gender, subspecies, or age within the observation periods.

Conclusions:

• Squirrel monkeys reared in nurseries display atypical self-directed behaviors when deprived of normal early stimulation.
• These findings align with observations in chimpanzees and Old World monkeys, highlighting a commonality in primate developmental responses.
• Nursery rearing environments may require enhanced enrichment to mitigate behavioral abnormalities in Saimiri sciureus.