Response to intruder number is related to quantity discrimination performance in a wild bird

Quantity discrimination abilities are considered a valuable skill for many aspects of life, including foraging, predator avoidance, and intergroup contests. Two types of experiments are often utilised to detect such abilities in animals: cognitive tasks in which individuals must choose between two quantities of food, and playback experiments of the vocalisations of differing numbers of intruding individuals. To date, no study has investigated whether individual performance in these two types of experiments is related. We presented wild Western Australian magpies (Gymnorhina tibicen dorsalis) with both a spontaneous quantity discrimination cognitive task and a playback experiment, to investigate quantity discrimination abilities, and to explore if performance on these experiments is related. We found that magpies (a) selected the greater quantity of food in the cognitive task and (b) responded more strongly to the playback of three callers compared to one caller, suggesting this species ..., , # Response to intruder number is related to quantity discrimination performance in a wild bird

**Blackburn G; Ashton BJ; Hunter H; Ridley AR**

**Corresponding author email:** [[e-mail]](mailto:[e-mail])

Data was collected between March and July in 2022 and 2023 on an established study population of Western Australian magpies located in Crawley and Guildford, Perth, Western Australia.

**Dataset DOI:** [10.5061/dryad.4qrfj6qps](10.5061/dryad.4qrfj6qps)

## Description of the data and file structure

This study investigates the quantity discrimination of Western Australian magpies using both a cognitive task and a playback experiment. Data includes cognitive testing from two years (2022 and 2023) on a spontaneous quantity discrimination task, and playback experiments from one year presenting birds with the territorial songs of 1, 2, and 3 calling extra-group conspecifics.

### Files and variables

#### File: repeatabilityoftotalscores.csv

**Description:** T...,