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Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology
RESEARCH ARTICLE (Open Access)

Evaluation of parameters of health in Australian fur seal (Arctocephalus pusillus doriferus) pups during early and mid-lactation

Jessalyn J. Taylor https://orcid.org/0009-0000-6181-6474 A * , Rebecca R. McIntosh https://orcid.org/0000-0003-3159-9581 B , Isabelle Charrier C and Rachael B. Gray A
+ Author Affiliations
- Author Affiliations

A Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camperdown, NSW 2050, Australia.

B Conservation Department, Phillip Island Nature Parks, Cowes, Vic 3922, Australia.

C Université Paris-Saclay, Institut des Neurosciences Paris-Saclay, CNRS, Saclay 91400, France.

* Correspondence to: jessalyn.taylor@sydney.edu.au

Handling Editor: Brad Law

Australian Journal of Zoology 73, ZO24041 https://doi.org/10.1071/ZO24041
Submitted: 12 December 2024  Accepted: 13 June 2025  Published: 7 July 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Seal Rocks, Victoria, is the largest Australian fur seal (Arctocephalus pusillus doriferus) breeding colony, but has one of the highest rates of decline in live pup abundance for the species. Establishing the current health status in the population is important as a point of comparison for future monitoring. This study aimed to develop haematological reference intervals and assess body condition in pups at Seal Rocks in early and mid-lactation. Pups from the 2021 and 2022 breeding seasons were sampled at 3–6 weeks of age (early lactation, n = 180) and 5–6 months of age (mid-lactation, n = 172). Haematological and morphometric parameters differed significantly (P < 0.05) between early and mid-lactation, but body condition did not. The differences in health parameters between early and mid-lactation relate to normal growth and ontogeny but highlight the increased vulnerability of pups in early lactation. These results provide an important reference point for future evaluations of health parameters in Australian fur seal pups.

Keywords: Australian fur seal, body condition, conservation management, haematology, marine conservation, pinniped, reference intervals, wildlife monitoring.

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