# Contrafreeloading and its influencing factors in budgerigars (Melopsittacus undulatus): Implications for their feeding and welfare

**Authors:** Yue Tao, Yu-Ting Zhu, Hui Li, Qi-Xin Zhang, Yong Zhu

PMC · DOI: 10.1017/awf.2025.15 · Animal Welfare · 2025-03-20

## TL;DR

Budgerigars show mixed tendencies to work for food, with factors like training and hunger affecting their choices, which can improve their welfare in captivity.

## Contribution

This study provides new insights into the intermediate contrafreeloading behavior of budgerigars and how training and hunger influence it.

## Key findings

- Budgerigars showed no significant preference in first choices between food containers of varying difficulty.
- Pre-trained budgerigars preferred highly challenging containers, while food-deprived ones chose less challenging ones.
- Only half of the budgerigars were identified as strong contrafreeloaders, indicating an intermediate CFL level overall.

## Abstract

Contrafreeloading (CFL) refers to animals’ tendency to prefer obtaining food through effort rather than accessing food that is freely available. Researchers have proposed various hypotheses to explain this intriguing phenomenon, but few studies have provided a comprehensive analysis of the factors influencing this behaviour. In this study, we observed the choice of alternative food containers in budgerigars (Melopsittacus undulatus) to investigate their CFL tendencies and the effects of pre-training, food deprivation, and effort required on the CFL tasks. The results showed that budgerigars did not exhibit significant difference in their first choices or the time interacting with less challenging versus more challenging food containers. Moreover, when evaluating each budgerigar’s CFL level, only half of them were identified as strong contrafreeloaders. Thus, we suggest that budgerigars exhibit an intermediate CFL level that lies somewhere between a strong tendency and the absence of such behaviour. Furthermore, we also found that food-deprived budgerigars tended to select less challenging food containers, and pre-trained budgerigars were more likely to choose highly challenging food containers than moderately challenging food containers, which means that the requirement of only a reasonable effort (access to food from moderately challenging food containers in this study) and the experience of pre-training act to enhance their CFL levels, whereas the requirement of greater effort and the experience of food deprivation act to decrease their CFL levels. Studying animal CFL can help understand why animals choose to expend effort to obtain food rather than accessing it for free, and it also has implications for setting feeding environments to enhance the animal welfare of captive and domesticated animals.

## Linked entities

- **Species:** Melopsittacus undulatus (taxon 13146)

## Full-text entities

- **Species:** Melopsittacus undulatus (budgerigar, species) [taxon 13146]

## Full text

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## Figures

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## References

35 references — full list in the complete paper: https://tomesphere.com/paper/PMC11949635/full.md

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Source: https://tomesphere.com/paper/PMC11949635