Disentangling olfactory and visual information used by field foraging birds

Area of Science:

• Ecology
• Behavioral Ecology
• Zoology

Background:

• Bird foraging strategies impact plant-insect networks and primary production.
• Forest insectivorous birds can use herbivore-induced plant volatiles (HIPVs) to find infested trees.
• The integration and prioritization of visual and olfactory cues in bird foraging remain unclear.

Purpose of the Study:

• To investigate the attraction of ground-foraging birds to HIPVs and visible prey in short vegetation.
• To determine how birds prioritize olfactory (HIPVs) and visual cues during foraging decisions.
• To assess the generality of HIPV attraction across different avian dietary guilds.

Main Methods:

• Conducted a series of foraging choice experiments with ground-foraging birds in farmland habitats.
• Manipulated the availability of HIPVs and visible prey to assess bird preferences.
• Observed bird choices under conditions with uniform vs. varied visual information.

Main Results:

• Birds initially preferred HIPVs when visual information was uniform across options.
• Birds preferred visible prey over HIPVs when both were presented as alternatives.
• Visual cues were prioritized over olfactory cues when visual information varied.

Conclusions:

• Olfactory cues are important for bird foraging when visual information is limited.
• Visual cues are preferred when they offer variation, overriding olfactory attraction.
• HIPV attraction is common across various bird dietary guilds, suggesting broad potential for biological pest control in agricultural settings.