A short note on extractive foraging behavior in gray snub-nosed monkeys.

Area of Science:

• Primate Ecology
• Behavioral Ecology
• Zoology

Background:

• Extractive foraging (EF) is crucial for primate survival, especially in resource-scarce environments.
• Colobine species are typically classified as non-extractive foragers, with limited quantitative research on their EF behaviors.

Purpose of the Study:

• To investigate the extractive foraging behavior of the gray snub-nosed monkey (Rhinopithecus brelichi).
• To assess the role of EF in the diet of R. brelichi, particularly during seasons with low food availability.

Main Methods:

• Observation of R. brelichi at Yangaoping in Fanjingshan National Nature Reserve.
• Categorization and quantification of 6 types of extractive foraging behaviors.
• Analysis of extracted food items, focusing on seeds, young bamboo, and invertebrates.

Main Results:

• Extracted foods constituted an average of 26.02% of feeding records.
• Seeds, young bamboo, and invertebrates were the most frequently extracted food types.
• Limited extractive foraging was observed during winter, a period of low food availability.

Conclusions:

• The study suggests R. brelichi should be recognized as an extractive forager.
• Findings challenge the hypothesis that EF primarily serves as a fallback strategy during lean seasons for this species.
• Highlights the need to include colobines in discussions on primate brain evolution and foraging strategies.