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RESEARCH ARTICLE (Open Access)

Integrating biobanking could produce significant cost benefits and minimise inbreeding for Australian amphibian captive breeding programs

Lachlan G. Howell https://orcid.org/0000-0003-1471-1674 A B I , Peter R. Mawson C , Richard Frankham D E , John C. Rodger A B , Rose M. O. Upton https://orcid.org/0000-0002-1324-6873 A B , Ryan R. Witt A B , Natalie E. Calatayud F G , Simon Clulow https://orcid.org/0000-0002-5700-6345 H and John Clulow A B
+ Author Affiliations
- Author Affiliations

A School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia.

B FAUNA Research Alliance, Kahibah, NSW 2290, Australia.

C Perth Zoo, Department of Biodiversity, Conservation and Attractions, PO Box 489, South Perth, WA 6951, Australia.

D Department of Biological Sciences, Macquarie University, Sydney, NSW 2019, Australia.

E Australian Museum, Sydney, NSW 2010, Australia.

F San Diego Zoo Institute for Conservation Research, San Pasqual Valley Road, Escondido, CA 92027, USA.

G Conservation Science Network, 24 Thomas Street, Mayfield, NSW 2304, Australia.

H Centre for Conservation Ecology and Genomics, Institute for Applied Ecology, University of Canberra, Bruce, ACT 2617, Australia.

I Corresponding author. Email: lachlan.howell@newcastle.edu.au

Reproduction, Fertility and Development 33(9) 573-587 https://doi.org/10.1071/RD21058
Submitted: 12 February 2021  Accepted: 23 March 2021   Published: 18 May 2021

Journal Compilation © CSIRO 2021 Open Access CC BY-NC

Abstract

Captive breeding is an important tool for amphibian conservation despite high economic costs and deleterious genetic effects of sustained captivity and unavoidably small colony sizes. Integration of biobanking and assisted reproductive technologies (ARTs) could provide solutions to these challenges, but is rarely used due to lack of recognition of the potential benefits and clear policy direction. Here we present compelling genetic and economic arguments to integrate biobanking and ARTs into captive breeding programs using modelled captive populations of two Australian threatened frogs, namely the orange-bellied frog Geocrinia vitellina and the white bellied frog Geocrinia alba. Back-crossing with frozen founder spermatozoa using ARTs every generation minimises rates of inbreeding and provides considerable reductions in colony size and program costs compared with conventional captive management. Biobanking could allow captive institutions to meet or exceed longstanding genetic retention targets (90% of source population heterozygosity over 100 years). We provide a broad policy direction that could make biobanking technology a practical reality across Australia’s ex situ management of amphibians in current and future holdings. Incorporating biobanking technology widely across this network could deliver outcomes by maintaining high levels of source population genetic diversity and freeing economic resources to develop ex situ programs for a greater number of threatened amphibian species.

Graphical Abstract Image

Keywords: anuran, artificial reproductive technologies, captive survival-assurance colonies, cryopreservation, frog, genome resource banking, IVF.


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