Functionally specialised birds respond flexibly to seasonal changes in fruit availability.

Area of Science:

• Ecology
• Zoology
• Botany

Background:

• Ecological networks, formed by species interactions, are generally stable.
• The temporal stability of consumer functional roles within these networks remains poorly understood.
• Functional specialization and flexibility are key traits influencing consumer roles.

Purpose of the Study:

• To investigate seasonal functional specialization of frugivorous birds on plant resources.
• To determine if closely related bird species share similar functional specialization.
• To assess the functional flexibility of birds in switching resources across seasons.

Main Methods:

• A trait-based approach was used to analyze plant-frugivore networks in the tropical Andes.
• Functional niche breadth and originality quantified bird specialization using plant trait space.
• Functional flexibility was calculated based on seasonal shifts in fruit preferences.

Main Results:

• Functional specialization varied more among bird species than across seasons.
• Phylogenetically similar bird species exhibited similar functional niche breadths and originality.
• Highly flexible birds showed narrow seasonal specialization, indicating adaptability.

Conclusions:

• Seasonally specialized birds demonstrate significant flexibility in resource switching.
• This flexibility challenges the notion of consistent year-round resource reliance by consumers.
• Consumer flexibility is a crucial, underappreciated mechanism for stabilizing ecological networks against disturbances.