Seed preference is only weakly linked to seed-type-specific feeding performance in a songbird

TL;DR

Canaries show varied seed preferences, but these preferences have little impact on how efficiently they handle different types of seeds.

Contribution

This study reveals that seed preference in canaries is only weakly linked to feeding performance, challenging assumptions about specialization in seed handling.

Findings

Canaries showed a wide range of seed preferences, including some that favored novel seed types.

Seed preference had few and weak effects on feeding efficiency and seed-handling performance.

The results suggest that efficient seed handling may not require extensive practice on specific seed types.

Abstract

The dehusking of seeds by granivorous songbirds is a complex process that requires fast, coordinated and sensory-feedback-controlled movements of beak and tongue. Hence, efficient seed handling requires a high degree of sensorimotoric skill and behavioural flexibility, since seeds vary considerably in size, shape and husk structure. To deal with this variability, individuals might specialise on specific seed types, which could result in greater seed handling efficiency of the preferred seed type, but lower efficiency for other seed types. To test this, we assessed seed preferences of canaries (Serinus canaria) through food choice experiments and related these to data of feeding performance, seed-handling skills and beak kinematics during feeding on small, spindle-shaped canary seeds and larger, spheroid-shaped hemp seeds. We found great variety in seed preferences among individuals: some had no clear preference, while others almost exclusively fed on hemp seeds, or even prioritized novel seed types (millet seed). Surprisingly, we only observed few and weak effects of seed preference on feeding efficiency. This suggests either that the ability to handle seeds efficiently can be readily applied across various seed types, or alternatively, that achieving high levels of seed-specific handling skills does not require extensive practice.

Summary: We studied how seed preference in canaries affects an individual's performance in handling various seed types. Surprisingly, despite considerable variability in preference, this only had weak influence on feeding performance.

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