Analyzing captive breeding outcomes to inform reintroduction practice: lessons from the pookila (Pseudomys novaehollandiae)

Kiarrah J Smith; Maldwyn J Evans; Iain J Gordon; Jennifer C Pierson; Jenny Newport; Adrian D Manning

doi:10.1093/jmammal/gyad056

Analyzing captive breeding outcomes to inform reintroduction practice: lessons from the pookila (Pseudomys novaehollandiae)

J Mammal. 2023 Jun 21;104(5):1047-1061. doi: 10.1093/jmammal/gyad056. eCollection 2023 Oct.

Authors

Kiarrah J Smith¹, Maldwyn J Evans^{1

2}, Iain J Gordon^{1

3

4

5

6}, Jennifer C Pierson^{1

7

8}, Jenny Newport¹, Adrian D Manning¹

Affiliations

¹ Fenner School of Environment and Society, The Australian National University, Acton, Australian Capital Territory 2601, Australia.
² Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-0032, Japan.
³ The James Hutton Institute, Dundee DD2 5DA, United Kingdom.
⁴ Central Queensland University, Townsville, Queensland 4810, Australia.
⁵ Land and Water, CSIRO, Townsville, Queensland 4810, Australia.
⁶ Lead, Protected Places Mission, National Environmental Science Program, Reef and Rainforest Research Centre, Cairns, Queensland 4870, Australia.
⁷ Australian Wildlife Conservancy, Subiaco East, Western Australia 6008, Australia.
⁸ Centre for Conservation Ecology and Genomics, Institute for Applied Ecology, University of Canberra, Canberra, Australian Capital Territory 2617, Australia.

Abstract

Captive breeding is often used to produce individuals for reintroduction programs in order to reestablish a species in an area where it has become locally extinct. To maximize the likelihood of establishing a self-sustaining population in the wild, an analysis of data from captive breeding programs is commonly undertaken to (1) increase the quantity of individuals and rate at which they can be released, and (2) maintain or improve the genetic and phenotypic quality of individuals. Here we demonstrate how the knowledge gained from these analyses can also be applied to decision-making during the design of subsequent reintroductions to further advance a reintroduction program toward success. We conducted an analysis of data from a captive breeding program for the threatened pookila (Pseudomys novaehollandiae, New Holland mouse) spanning 6 years. We found evidence for relationships between the reproductive output of pookila and behavioral, demographic, experiential, health, and physiological predictors. Based on a biological interpretation of these results, and with reference to a checklist of all known translocation tactics, we recommend 11 specific design elements to maximize the probability of pookila reproduction postrelease (thereby improving the likelihood of reintroduction success). These recommendations should be interpreted as hypotheses to be evaluated and refined in future reintroduction trials for the pookila. The uncertainty around the postrelease survival and reproduction of a species that is common in reintroduction practice warrants the creative use of existing data to inform adaptive management. Indeed, there is a wealth information in well-kept captive breeding records that is currently underused by reintroduction practitioners. The direct integration of knowledge derived from captive breeding (where available) with decision-making for reintroductions, as described here, will help navigate these uncertainties, which would benefit the conservation of both understudied and well-known species around the world.

Keywords: captive breeding; conservation; reintroduction; reproduction; rodent; translocation tactics.