Modeling genetic benefits and financial costs of integrating biobanking into the conservation breeding of managed marsupials

Managed breeding programs are an important tool in marsupial conservation efforts but may be costly and have adverse genetic effects in unavoidably small captive colonies. Biobanking and assisted reproductive technologies (ARTs) could help overcome these challenges, but further demonstration of their potential is required to improve uptake. We used genetic and economic models to examine whether supplementing hypothetical captive populations of dibblers (Parantechinus apicalis) and numbats (Myrmecobius fasciatus) with biobanked founder sperm through ARTs could reduce inbreeding, lower required colony sizes, and reduce program costs. We also asked practitioners of the black-footed ferret (Mustela nigripes) captive recovery program to complete a questionnaire to examine the resources and model species research pathways required to develop an optimized biobanking protocol in the black-footed ferret. We used data from this questionnaire to devise similar costed research pathways for Australian marsupials. With biobanking and assisted reproduction, inbreeding was reduced on average by between 80% and 98%, colony sizes were on average 99% smaller, and program costs were 69- to 83-fold lower. Integrating biobanking made long-standing captive genetic retention targets possible in marsupials (90% source population heterozygosity for a minimum of 100 years) within realistic cost frameworks. Lessons from the use of biobanking technology that contributed to the recovery of the black-footed ferret include the importance of adequate research funding (US$4.2 million), extensive partnerships that provide access to facilities and equipment, colony animals, appropriate research model species, and professional and technical staff required to address knowledge gaps to deliver an optimized biobanking protocol. Applied research investment of A$133 million across marsupial research pathways could deliver biobanking protocols for 15 of Australia's most at-risk marsupial species and 7 model species. The technical expertise and ex situ facilities exist to emulate the success of the black-footed ferret recovery program in threatened marsupials using these research pathways. All that is needed now for significant and cost-effective conservation gains is greater investment by policy makers in marsupial ARTs.

Emerging arguments for reproductive technologies in wildlife and their implications for assisted reproduction and conservation of threatened marsupials

Assisted reproductive technologies (ARTs) have significant potential to make a meaningful contribution to the conservation of threatened wildlife. This is true of Australia's iconic, and endangered koala (Phascolarctos cinereus). If developed, ARTs could offer a solution to manage genetic diversity and costs in breeding programs and may provide frozen repositories for either insurance or the practical production of genetically resilient koalas for release and on-ground recovery. Holding back the wider use of ARTs for koalas and other wildlife is a lack of funding to close the remaining knowledge gaps in the marsupial reproductive sciences and develop the reproductive tools needed. This lack of funding is arguably driven by a poor understanding of the potential contribution ARTs could make to threatened species management. We present a review of our cross-disciplinary and accessible strategy to draw much needed public attention and funding for the development of ARTs in wildlife, using emerging cost and genetic modelling arguments and the koala as a case study.

Modelling Genetic Benefits and Financial Costs of Integrating Biobanking into the Captive Management of Koalas

Simple Summary

Managed wildlife breeding faces high costs and genetic diversity challenges associated with caring for small populations. Biobanking (freezing of sex cells and tissues for use in assisted breeding) and associated reproductive technologies could help alleviate these issues in koala captive management by enhancing retention of genetic diversity in captive-bred animals and lowering program costs through reductions in the size of the required live captive colonies. Australia’s zoos and wildlife hospitals provide rare opportunities to refine and cost-effectively integrate these tools into conservation outcomes for koalas due to extensive already-existing infrastructure, technical expertise, and captive animals.

Abstract

Zoo and wildlife hospital networks are set to become a vital component of Australia’s contemporary efforts to conserve the iconic and imperiled koala (Phascolarctos cinereus). Managed breeding programs held across zoo-based networks typically face high economic costs and can be at risk of adverse genetic effects typical of unavoidably small captive colonies. Emerging evidence suggests that biobanking and associated assisted reproductive technologies could address these economic and genetic challenges. We present a modelled scenario, supported by detailed costings, where these technologies are optimized and could be integrated into conservation breeding programs of koalas across the established zoo and wildlife hospital network. Genetic and economic modelling comparing closed captive koala populations suggest that supplementing them with cryopreserved founder sperm using artificial insemination or intracytoplasmic sperm injection could substantially reduce inbreeding, lower the required colony sizes of conservation breeding programs, and greatly reduce program costs. Ambitious genetic retention targets (maintaining 90%, 95% and 99% of source population heterozygosity for 100 years) could be possible within realistic cost frameworks, with output koalas suited for wild release. Integrating biobanking into the zoo and wildlife hospital network presents a cost-effective and financially feasible model for the uptake of these tools due to the technical and research expertise, captive koala colonies, and ex situ facilities that already exist across these networks.

Drone thermal imaging technology provides a cost-effective tool for landscape-scale monitoring of a cryptic forest-dwelling species across all population densities

Abstract Context Drones, or remotely piloted aircraft systems, equipped with thermal imaging technology (RPAS thermal imaging) have recently emerged as a powerful monitoring tool for koala populations. Before wide uptake of novel technologies by government, conservation practitioners and researchers, evidence of greater efficiency and cost-effectiveness than with other available methods is required. Aims We aimed to provide the first comprehensive analysis of the cost-effectiveness of RPAS thermal imaging for koala detection against two field-based methods, systematic spotlighting (Spotlight) and the refined diurnal radial search component of the spot-assessment technique (SAT). Methods We conducted various economic comparisons, particularly comparative cost-effectiveness of RPAS thermal imaging, Spotlight and SAT for repeat surveys of a low-density koala population. We compared methods on cost-effectiveness as well as long-term costs by using accumulating cost models. We also compared detection costs across population density using a predictive cost model. Key results Despite substantial hardware, training and licensing costs at the outset (>A$49 900), RPAS thermal imaging surveys were cost-effective, detecting the highest number of koalas per dollar spent. Modelling also suggested that RPAS thermal imaging requires the lowest survey effort to detect koalas within the range of publicly available koala population densities (~0.006–18 koalas ha−1) and would provide long-term cost reductions across longitudinal monitoring programs. RPAS thermal imaging would also require the lowest average survey effort costs at a landscape scale (A$3.84 ha−1), providing a cost-effective tool across large spatial areas. Conclusions Our analyses demonstrated drone thermal imaging technology as a cost-effective tool for conservation practitioners monitoring koala populations. Our analyses may also form the basis of decision-making tools to estimate survey effort or total program costs across any koala population density. Implications Our novel approach offers a means to perform various economic comparisons of available survey techniques and guide investment decisions towards developing standardised koala monitoring approaches. Our results may assist stakeholders and policymakers to confidently invest in RPAS thermal imaging technology and achieve optimal conservation outcomes for koala populations, with standardised data collection delivered through evidence-based and cost-effective monitoring programs.

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

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.

Trialling a real-time drone detection and validation protocol for the koala (Phascolarctos cinereus)

Remotely piloted aircraft system (RPAS), or drone, technology has emerged as a promising survey method for the cryptic koala. We demonstrate an in-field protocol for wild koala RPAS surveys which provides real-time validation of thermal signatures. During 15 trial flights using a quadcopter drone (DJI Matrice 200 v2) we successfully detected and validated koala thermal signatures (n=12) using two in-field approaches: validation by on-ground observer (n=10) and validation using 4K footage captured and reviewed directly after the survey (n=2). We also provide detectability considerations relative to survey time, temperature, wildlife–RPAS interactions and detection of non-target species, which can be used to further inform RPAS survey protocols.

Real-time drone derived thermal imagery outperforms traditional survey methods for an arboreal forest mammal

Koalas (Phascolarctos cinereus) are cryptic and currently face regional extinction. The direct detection (physical sighting) of individuals is required to improve conservation management strategies. We provide a comparative assessment of three survey methods for the direct detection of koalas: systematic spotlighting (Spotlight), remotely piloted aircraft system thermal imaging (RPAS), and the refined diurnal radial search component of the spot assessment technique (SAT). Each survey method was repeated on the same morning with independent observers (03:00-12:00 hrs) for a total of 10 survey occasions at sites with fixed boundaries (28-76 ha) in Port Stephens (n = 6) and Gilead (n = 1) in New South Wales between May and July 2019. Koalas were directly detected on 22 occasions during 7 of 10 comparative surveys (Spotlight: n = 7; RPAS: n = 14; and SAT: n = 1), for a total of 12 unique individuals (Spotlight: n = 4; RPAS: n = 11; SAT: n = 1). In 3 of 10 comparative surveys no koalas were detected. Detection probability was 38.9 ± 20.03% for Spotlight, 83.3 ± 11.39% for RPAS and 4.2 ± 4.17% for SAT. Effective detectability per site was 1 ± 0.44 koalas per 6.75 ± 1.03 hrs for Spotlight (1 koala per 6.75 hrs), 2 ± 0.38 koalas per 4.35 ± 0.28 hrs for RPAS (1 koala per 2.18 hrs) and 0.14 ± 0.14 per 6.20 ± 0.93 hrs for SAT (1 koala per 43.39 hrs). RPAS thermal imaging technology appears to offer an efficient method to directly survey koalas comparative to Spotlight and SAT and has potential as a valuable conservation tool to inform on-ground management of declining koala populations.

Evaluating amphibian biobanking and reproduction for captive breeding programs according to the Amphibian Conservation Action Plan objectives

The Amphibian Conservation Action Plan (ACAP), published in 2007, is a formal document of international significance that proposed eleven relevant actions for global amphibian conservation. Action seven of the ACAP document addresses the use of amphibian captive programs as a conservation tool. Appendix material under this action explores the potential use of Genome Resource Banking (biobanking) as an urgently needed tool for these captive programs. ACAP proposed twelve objectives for Genome Resource Banking which exhibit little emphasis on reproduction as a vital underlying science for amphibian Captive Breeding Programs (CBP's). Here we have reassessed the original twelve ACAP objectives for amphibian reproduction and biobanking for CBP's as a contribution to future ACAP review processes. We have reviewed recent advances since the original objectives, as well as highlighted weaknesses and strengths for each of these objectives. We make various scientific, policy and economic recommendations based on the current reality and recent advances in relevant science in order to inform future ACAP towards new global objectives. The number of amphibian CBP'S has escalated in recent years and reproductive success is not always easily accomplished. Increases in applied and fundamental research on the natural history and reproductive biology of these species, followed by the appropriate development and application of artificial reproductive technologies (ART's) and the incorporation of genome resource banks (GRB's), may turn CBP's into a more powerful tool for amphibian conservation.

Deconstructing compassionate conservation

Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public.