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Australian Mammalogy Australian Mammalogy Society
Journal of the Australian Mammal Society
RESEARCH ARTICLE

Interactions between adult male koalas and dependent joeys in a high-density population

Darcy J. Watchorn A * and Desley A. Whisson A
+ Author Affiliations
- Author Affiliations

A School of Life and Environmental Sciences (Burwood Campus), Deakin University, Geelong, Vic., Australia.

* Correspondence to: dwatchorn@deakin.edu.au

Handling Editor: Ross Goldingay

Australian Mammalogy 46, AM23012 https://doi.org/10.1071/AM23012
Submitted: 28 March 2023  Accepted: 6 November 2023  Published: 7 December 2023

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Australian Mammal Society.

Abstract

During a study of interactions among koalas, we observed interactions between adult males and dependent joeys. Most were passive in nature, suggesting that interactions with adult males are not a major threat to joey survival. However, one male–joey interaction resulted in a joey falling approximately 7 m to the ground, an incident that may have resulted in the death of the joey had we not intervened. We suggest that there is potential for infant death to occur under the generalised aggression hypothesis for koalas, although further observations are needed.

Keywords: copulation, generalised aggression, high-density population, infant death, infanticide, joey, juvenile, koala, marsupial, Phascolarctos cinereus.

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