Showcasing the application of genetics for the conservation management of austral birds

The need for a holistic approach to avian conservation

Globally, at least 40% of bird species are in decline and one in eight species are at risk of extinction (Birdlife International 2018a). Owing to the complex and interconnected causes of species’ declines, it is recognised that effective conservation requires a holistic approach that encompasses a wide variety of disciplines (Liu et al. 2015). However, some disciplines have been more readily adopted by conservationists than others.

The importance of genetic factors for species’ persistence is well established theoretically and empirically, but genetic data are consistently missing from conservation management planning. A role for genetics in conservation was first suggested in 1974 (Frankel 1974), and conservation genetics became established as a discipline in the early 1980s (Soulé and Wilcox 1980; Frankel and Soulé 1981; Schonewald-Cox et al. 1983). There are now journals dedicated explicitly to the subject (e.g. Conservation Genetics) and a multitude of publications demonstrating the real-world importance of genetics to conservation, including of bird species (Frankham 2005, 2010; Mackintosh and Briskie 2005; Grueber et al. 2010; Allendorf 2017; Taylor et al. 2017a). In spite of this, outside the USA, the vast majority of species conservation plans do not include genetic considerations (Pierson et al. 2016; Cook and Sgrò 2017). This has created an implementation gulf between genetics and conservation that has been termed the conservation genetics gap (Taylor et al. 2017b).

The conservation genetics gap is seemingly driven by multiple factors. Historically, debates over the importance of genetics to conservation in the scientific literature (e.g. Lande 1988; Caro and Laurenson 1994; Caughley 1994) may have dissuaded practitioners from considering genetic factors in conservation plans, steering them towards focussing on more pressing concerns such as invasive species (Jamieson et al. 2006). The use of field-specific jargon in much of the genetics literature may also be responsible for its lack of adoption as a practical conservation tool (Hoban et al. 2013). More recent data suggest that conservation practitioners do see the value of genetics to conservation, however practitioners often feel they lack the knowledge to include genetic data effectively in their management plans, and do not always know what issues genetics can be applied to (Taylor et al. 2017b; Holderegger et al. 2019). Thus, showcasing the ways genetic data can be used to conserve threatened species is important for increasing the implementation of conservation genetics and creating more holistic, and thus effective, species management strategies.

This Emu Austral Ornithology special issue – Conservation Genetics: Showcasing Applications in Austral Birds – explores the diversity of conservation-relevant questions for bird species that can be tackled using genetic tools. All 14 data papers published in this issue, emphasise the application of genetic data to a conservation-related problem in austral birds. Our aim was that, regardless of whether or not readers are familiar with the scientific tools employed, they will understand the relevance of the question being addressed with those tools. The result is an impressively diverse collection of studies that not only illustrates the breadth of conservation issues that can be and are being addressed using genetic tools, but also reminds us of the value of the effective application of existing tools combined with sound understanding of theory. Conservation genetics is, itself, rapidly evolving thanks to the fast-paced development of genomic technologies. The studies presented here demonstrate the exciting opportunities presented by new genomics tools and the value of older tools (such as microsatellites and Sanger-sequenced approaches) when properly applied to conservation questions.

In the discussion below, we include two highly relevant papers originally intended for inclusion in this special issue but published in 2020 (Joseph et al. 2020; Lohr et al. 2020).

Conservation units and taxonomy

One fundamental conservation question that genetic data can assist with is ‘What units should be conserved?’ These units may be at the population level (e.g. evolutionarily significant units (ESUs)), or at a species or subspecies level (Ryder 1986; Moritz 1994). While debates regarding what qualifies as a species or subspecies continue in ornithology and elsewhere (Wang et al. 2020; Cadena and Zapata 2021), effective conservation is impossible without clear evidence delineating the population boundaries of each management unit (Fitzpatrick et al. 2015). In most cases, conservation units have phenotypic and genetic signatures of divergence that clearly delineate them and justify their management as separate species, subspecies, or populations. However, such classifications are not always straightforward owing to variables such as recent divergence times, processes such as incomplete lineage sorting and hybridisation, and cases where phenotypic characteristics are misleading for taxonomy. Sometimes, different species or units show little morphological variation or, conversely, a phenotypic trait is extremely plastic, leading to great differentiation within a species or unit (Dussex et al. 2018). Four papers in this special issue demonstrate the advantage of using phenotypic data in tandem with genetic data and phylogenetic approaches to provide a stronger framework to help inform conservation management (Burbidge et al. 2021; Grosser et al. 2021; Joseph et al. 2020; Joseph et al. 2021).

Grosser et al. (2021) showcase the use of genetic data in delineating taxa or conservation units previously described based on morphology alone. Using range-wide genetic analysis of mitochondrial and nuclear sequence data from five currently recognised species of Diving Petrels (genus Pelecanoides), they confirm that the recently described Whenua Hou Diving Petrel/Kuaka Whenua Hou (Pelecanoides whenuahouensis) is indeed genetically distinct from its sister taxon, the South Georgian Diving Petrel (P. georgicus). This genetic distinction is a critical step given that the Whenua Hou Diving Petrel was only recently described based on subtle morphological differences (Fischer et al. 2018). Whether the Whenua Hou Diving Petrel is distinct enough to warrant species status or is better recognised as a subspecies of the South Georgian Diving Petrel is still debatable (Grosser et al. 2021). Irrespective of its taxonomic status, the Whenua Hou Diving Petrel certainly represents a distinct genetic unit for conservation, which desperately needs protecting; it currently consists of just 200 adults breeding in 0.018 km² of fragile dune habitat (Fischer et al. 2020).

In a similar quest to delineate morphologically similar species units, Joseph et al. (2021) demonstrate the additional power and information provided by large panels of genetic markers to revise previous taxonomies. New data for the Golden Whistler species complex (Pachycephala spp.) from 17,269 genome-wide single nucleotide polymorphisms (SNPs) suggest that the apparently close relationship of whistlers from southern Australia currently recognised as Pachycephala pectoralis fuliginosa with Golden Whistler P. pectoralis from eastern Australia inferred from previous studies based on mitochondrial DNA actually results from hybridisation and extensive introgression between the two. Instead of being a subspecies of Golden Whistler, P. p. fuliginosa is actually more closely related to the recently described Western Whistler P. occidentalis species, with which it shares most phenotypic characters. Rules of nomenclature dictate a new species designation: Western Whistler (Pachycephala fuliginosa) with two subspecies: P. f. fuliginosa in the south and P. f. occidentalis in the west. The genetic results of Joseph et al. (2021) both expand the range that needs to be managed for conservation of Western Whistler by around 1500 km and highlight the issues of relying solely on mitochondrial sequence data to designate evolutionarily significant units.

A large SNP panel is also brought to bear on the taxonomy of the morphologically conservative fieldwrens (Calamanthus spp.) (Burbidge et al. 2021). This widespread Australian species complex has undergone several taxonomic revisions in the past 100 years, making conservation management decisions decidedly challenging. Burbidge et al. (2021) use a combination of 6627 SNPs and mitochondrial DNA, morphometrics, plumage colour and vocalisation data to suggest that there are two species of fieldwren: the Striated Fieldwren (C. fuliginosus) and the Rufous Fieldwren (C. campestris). However, when it comes to subspecies and evolutionarily significant units, the picture remains unclear; the authors discuss contrasting strands of evidence while suggesting that, for now at least, three subspecies of Rufous Fieldwren should be recognised: C. c. campestris, C. c. rubiginosus and C. c. hartogi, the latter of which is restricted to Dirk Hartog Island and is of significant conservation concern.

At the other end of the taxonomic and phenotypic distinctiveness scale is Joseph et al. (2020)’s exploration of genus-level systematics among the distinctive, boldly patterned lorikeets (Psittaciformes: Loriini). Despite their showy plumages, this group has had a long history of uncertain and changeable taxonomy across both its often polytypic species complexes and at the genus level. Zooming out from the species versus subspecies question, Joseph et al. (2020) use a combination of genomic and quantitative colour data to tackle long-standing genus-level taxonomic questions and produce a refined genus-level taxonomy for lorikeets. Six species are moved to three new genera (Saudareos, Synorhacma, Charmosynoides) to create a more stable taxonomy that can be used to guide conservation and management of lorikeets in the future. In particular, the identification of these new genera highlights the conservation importance of the Solomon Islands and Indonesia as centres of genus-level endemism for lorikeets.

Population connectivity and structure

Estimates of gene flow (or lack thereof) between populations of a species or subspecies are helpful indicators of how connected these units are or were in the past. Across all taxa, populations are becoming increasingly fragmented due to habitat loss (e.g. Athrey et al. 2012; Stevens et al. 2018). Meanwhile, other populations have been separated for thousands of years via natural events such as glaciation (e.g. Weston and Robertson 2015; Grosser et al. 2017). Understanding population structure can assist conservation managers in retaining or restoring genetic diversity (and thus adaptive potential) via conservation management. Studies of population structure are on a sliding scale with taxonomy research. However, where traditional phylogenetic taxonomy work, such as the studies highlighted in the previous section, tend to be tree-based, studies of genetic structure focus more on population genetic differentiation and/or migration statistics, and look for clinal patterns such as isolation-by-distance (IBD) across a landscape. Five studies in this special issue take a genetic structure approach to addressing conservation questions, and they range from birds that cannot fly at all to some of the most famous aerial wanderers on the planet (Beckmann et al. 2021; Brown et al. 2021; Lohr et al. 2020; Taylor et al. 2021; Wold et al. 2021).

Kiwi (Apteryx spp.) are famously flightless, but what does this mean for connectivity within kiwi species in a changing landscape? The facts that kiwi do not fly and are relatively territorial and monogamous mean one might expect to see a pattern of IBD within kiwi species. The IBD would dictate that individuals are more genetically similar to geographically closer conspecifics than to those further away (Wright 1943, 1946). This means that if one sampled only from either end of the species’ range, the birds would appear very genetically different, but this would miss the bigger picture. For many kiwi species, habitat fragmentation and population declines have disrupted historical connectivity and patterns of IBD (e.g. Ramstad et al. 2013). Here Taylor et al. (2021) explore population connectivity in the Great Spotted Kiwi/Roroa (Apteryx haastii), which are unusual among kiwi in that they still occupy the majority of their historic range. Even with just a small panel of microsatellite markers, Taylor et al. (2021) show that it is possible to detect that Great Spotted Kiwi do, indeed show signals of IBD at various spatial scales, and that this has helped retain the greatest genetic diversity known for any kiwi species. This has implications for conservation management and specifically, translocation planning (discussed further below), if genetic diversity is to be maintained in this species.

Other bird species show far greater connectivity and genetic mixing over large distances than might be expected given their size; however, these species could be experiencing disruptions in connectivity due to habitat loss. Two studies in this special issue address this matter in very different species and with quite different conclusions (Beckmann et al. 2021; Lohr et al. 2020).

Using 17 microsatellite markers, Beckmann et al. (2021) find very little structure among four populations of Flame Robins (Petroica phoenicea) spread over 690 km, indicating high gene flow historically. Critically, although Flame Robins occupy a relatively large range down the south-east coast of mainland Australia and on to Tasmania, their breeding range is restricted to high elevations. Their breeding habitat is disappearing rapidly, likely causing disjunct high elevation populations to become more isolated and reducing gene flow. While this is not represented in the current genetic snapshot, continued genetic monitoring over time will be important to establish where connectivity is being lost and to mitigate this loss, especially as climate change exacerbates the situation by reducing the amount of suitable habitat even further (Beckmann et al. 2021).

Despite being Australia’s most common owl, a combination of increased urbanisation, increased agriculture and use of rodent poison seems to have sent Southern Boobooks (Ninox boobook) into decline (Lohr 2018). Lohr et al. (2020) use a combination of eight microsatellite markers and mark–recapture data on banded juveniles from Western Australia to suggest that, in spite of habitat loss, the population displays a surprising degree of panmixia across their broad range. The mark–recapture data hint that this is likely in part because juvenile Southern Boobooks can disperse up to 52 km, enabling them to cross degraded habitat and find viable locations. Southern Boobooks are also dietary generalists, which probably helps them persist in urban areas. The authors conclude that, while habitat fragmentation is not currently causing genetic fragmentation, habitat loss is potentially still driving a loss in Southern Boobook owls overall, even if connectivity is being maintained via dispersal (Lohr et al. 2020).

In contrast to many land birds, distance poses almost no object to dispersal for seabird taxa such as albatrosses, but gene flow between colonies can still be extremely limited due to behavioural factors (Munro and Burg 2017). This certainly seems to be the case for Northern and Southern Buller’s Albatross (Thalassarche bulleri platei and T. b. bulleri) according to Wold et al. (2021). Here, thousands of SNP markers are used to establish that asynchronous breeding (2.5 months apart) is acting as an effective barrier to gene flow between these two subspecies, despite a relatively low distance between their respective colonies. It is possible that these subspecies should be elevated to full species status as a result of their reproductive isolation. Regardless of their taxonomic status, the genetic separation of Northern and Southern Buller’s Albatross necessitates their treatment as two management units, which likely requires a reassessment of their threat status given that they are currently listed jointly on both the IUCN RedList and the New Zealand Department of Conservation (Robertson et al. 2017; Birdlife International 2018b) and given that both are common fisheries bycatch (Birdlife International 2021).

Another long-distance disperser, but one potentially posing different conservation considerations, is the Pacific Black Duck (Anas superciliosa). These prolific dispersers have managed to spread right across Australia, out to New Guinea and the Solomon Islands, and over to New Zealand. This geographical spread and subsequent separation have led to the differentiation of three subspecies, which Brown et al. (2021) confirm to be genetically distinct using a combination of mitochondrial DNA and nuclear intron sequence data. Interestingly, these three subspecies have differing habitats, generating different conservation concerns and management actions for each (Brown et al. 2021). Genetic data for Pacific Black Ducks also suggest that there is still the occasional Australian Pacific Black Duck introducing new genetic variants into the New Zealand population (in addition to genetic swamping by hybridisation with mallards [Anas platyrhynchos]), and raise the question of whether the genetic differences seen in the Solomon Islands Pacific Black Duck are due to adaptation or genetic drift (Brown et al. 2021).

Translocation management

Understanding population structure and genetic diversity can be crucial for managing conservation translocations (Weeks et al. 2015). Translocations can involve moving individuals of a given species to a new location outside their known historical range (assisted colonisation), moving individuals back into a previously occupied area that the species has been extirpated from (reintroduction), or ‘topping up’ an extant population of the same species (reinforcement) (Seddon 2010). Thus, understanding where to source individuals from to maximise genetic diversity while preserving important genetic structure is useful information for translocation planning. We present four papers in this special issue that show how genetic data can help inform decisions about translocation management (Bolton et al. 2021; Cowen et al. 2021; Dwyer et al. 2021; Taylor et al. 2021).

In the Great Spotted Kiwi example described above (Taylor et al. 2021), the IBD structure and resultant high genetic diversity suggest some clear considerations for any translocations of that species in the future. In this case, maintaining the current genetic structure should be a goal of any future translocation efforts. This means not translocating birds from one end of the range to the other and, if attempts are being made to fill gaps in the distribution, these should be filled with birds from neighbouring locations where possible.

To maximise genetic diversity and guard against stochastic losses, translocated populations should be founded with a representative number of individuals (Tracy et al. 2011; Weeks et al. 2015). For threatened species, this is often not feasible. Cowen et al. (2021) use genetic data to explore the efficacy of translocations in the Noisy Scrub-bird/Tjimiluk (Atrichornis clamosus), which was thought to be extinct until a population of fewer than 100 birds was rediscovered in the 1960s in south-west Australia. This bird is cryptic and difficult to capture. As a result, translocated Noisy Scrub-bird populations were founded with 31, 10 and 11 individuals (with the latter group including just three females). Using a panel of eight microsatellites, Cowen et al. (2021) demonstrate that these founder groups did capture the genetic diversity available in the source population, but that all populations are relatively inbred. The most pressing threat for Noisy Scrub-birds in the short term is likely bushfire rather than inbreeding, but bushfires could act to keep populations small, exacerbating inbreeding and loss of genetic diversity (Cowen et al. 2021). As is often the case for small translocated/relict populations, protection against stochastic events, and monitoring and management of genetic diversity are likely both required for Noisy Scrub-birds if they are to continue to survive. Additional translocations to predator-free islands are also being considered to give this species a fighting chance (Cowen et al. 2021).

Predator-free islands, whether true oceanic islands or isolated mainland fragments, are popular sites for Australasian avian translocations. In one of two review papers in this special issue, Dwyer et al. (2021) consider translocations to island sites through the lens of retaining genetic diversity and, thus, long-term adaptive potential. The review emphasises the problem that many translocation programmes are not monitored for long enough to establish whether or not there are risks of genetic issues, especially in the case of long-lived species. Dwyer et al. (2021) also provide a useful summary of the various tools available to conduct genetic monitoring and some of the genetic processes we might expect to see in translocated island populations. The review (Dwyer et al. 2021) is a go-to introduction for anyone trying to effectively integrate genetic monitoring into an avian translocation plan.

For species that are extinct in the wild, such as the Guam Kingfisher/Sihek (Todiramphus cinnamominus) or the Hawaiin Crow/’Alalā (Corvus hawaiiensis), there may not be any wild source populations remaining for translocations, and ex situ populations may be needed (VanderWerf 2012; Trask et al. 2021). Ex situ populations often refer to zoos or sanctuaries but, for avian species in particular, large numbers of some taxa are held by private breeders. While zoo populations tend to be managed via studbooks to try and avoid inbreeding and maintain genetic variation (e.g. WAZA 2010), private collections are less likely to have that kind of system in place and so their value for conservation translocations is questionable. Bolton et al. (2021) explore this problem using the Gouldian Finch (Chloebia gouldiae), a threatened estrilidid finch native to northern Australia, but held by a large number of private breeders across the country. A combination of mitochondrial DNA and data from 12 microsatellite loci suggest that privately owned Gouldian Finches display lower genetic variation and higher inbreeding than their wild counterparts (Bolton et al. 2021). The genotypes for the bright head colours that have made these birds so popular with breeders are known to be associated with important functional traits (e.g. Pryke et al. 2007; Pryke 2007). Head colour genotype frequencies in captive Gouldian Finches are very different from those in the wild (Bolton et al. 2021). Together with concerns about adaptation to captivity, these data mean that, currently, Gouldian Finches from private collections should likely not be released back into the wild (Bolton et al. 2021). This finding emphasises the importance of proper management of ex situ populations if they are to be used in species reintroductions.

What has been lost and what remains?

Museum specimens or prehistoric remains can help us look back through time to understand what genetic diversity and, thus, adaptive capacity have been lost. Such an approach is suggested by Cowen et al. (2021) to compare the genetic diversity of extant populations of Noisy Scrub-birds with museum specimens collected before the presumed extirpation of Noisy Scrub-birds from much of their range. These museum data would help ascertain what diversity has been lost from this species, as a result of its drastic decline (Cowen et al. 2021). Two papers in this special issue use museum samples to assess what genetic or phylogenetic diversity has been lost from different bird species (Grosser et al. 2021; Ramstad et al. 2021).

Little Spotted Kiwi/Kiwi Pukupuku (Apteryx owenii) are known to have the lowest genetic diversity of any kiwi species due to a bottleneck of, at most, five birds (Ramstad et al. 2010, 2013). Over the course of the nineteenth and twentieth centuries, this smallest species of kiwi went from being widespread throughout New Zealand’s South Island to being restricted to one island population founded with just five birds in the early 1900s. However, the degree of genetic diversity lost during this bottleneck has not previously been established. Ramstad et al. (2021) use an analysis of mitochondrial DNA and a panel of 15 microsatellites for modern-day and historical Little Spotted Kiwi samples to suggest that the losses have been huge. Seventy-eight per cent fewer mitochondrial haplotypes and 52% fewer microsatellite alleles are seen in modern birds compared with historical samples. Little Spotted Kiwi were recently assigned the improved RedList status of Near Threatened (previously Vulnerable) because of human-assisted population expansion (Birdlife International 2016). It has been argued repeatedly that this amended ranking did not account for the massively depauperate genetic diversity and inherent inbreeding in the species (Ramstad et al. 2013; Taylor et al. 2017a). These historical genetic data lend further weight to the idea that low genetic diversity in Little Spotted Kiwi is not the norm, putting the species at risk from disease events and other environmental challenges. Fortunately, genetic data is now integrated into management planning for this species (Germano et al. 2018).

Genetic data from historic samples can also help ascertain where species may have existed historically – and where they did not, as shown by Grosser et al. (2021) in Whenua Hou Diving Petrels. The breeding range of the Whenua Hou Diving Petrel is currently restricted to one very small area on a small island, but this bird is thought to have been more widespread historically (Fischer et al. 2018). In fact, a paratype specimen for the species was collected on the Auckland Islands, some 400 km south of Whenua Hou. However, genetic analysis suggests this specimen is actually a South Georgian Diving Petrel. This begs the question of whether the Whenua Hou species ever resided on the Auckland Islands at all (Grosser et al. 2021) and thus whether that site would be suitable for a Whenua Hou population restoration in future.

In addition to looking backwards, genetic data can also alert us to potential future issues, even when species appear to be demographically stable. Cowles et al. (2021) examine the potential future of the Hermit White-Eye (Zosterops murphyi) and the Solomon Islands White-Eye (Z. kalumbangrae). Both species are endemic to the Solomon Islands and both have relatively large census populations (~64,412 and 114,781, respectively) in spite of habitat loss and other landscape changes (Cowles et al. 2021). However, analyses using a panel of 1508 SNPs suggest that the effective population size in each species (Ne) is much lower (796.1 and 694.5) (Cowles et al. 2021). This means that the number of individuals contributing genetically to the population of each species is a fraction of the census population. Although not an immediate issue, the disparity discovered suggests a potential problem for the future and a clear need for continued genetic monitoring to predict and safeguard these white-eye species against future declines (Cowles et al. 2021).

Detecting hidden strategies

Reproductive strategies such as extra-pair parentage are potentially employed as inbreeding avoidance tactics (Brouwer and Griffith 2019), but are often challenging to detect via observation alone. This is particularly important when assessing inbreeding and relatedness within an at-risk species or population. The Chatham Island Black Robin/Karure (Petroica traversi) is perhaps one of the most famously inbred birds of all time, having been reduced to just one female and four males in 1980 and all present-day individuals being descended from just one breeding pair (Butler and Merton 1992; Massaro et al. 2018). The species has been monitored via intensive observation of individually marked birds, and these observations are used to maintain a pedigree for the species, but are the observers missing any sneaky extra-pair copulations? Forsdick et al. (2021) use genetic data from a panel of 15 microsatellites to reveal an extra pair paternity (EPP) rate of 20% in one of the two extant populations of Chatham Island Black Robin. These EPPs likely render the existing behaviour-based pedigree inaccurate to some degree, which will have a knock-on effect on estimates of inbreeding and relatedness (Forsdick et al. 2021). The 20% EPP figure is likely an underestimate as the extremely high genetic similarity of individual Chatham Island Black Robins means that the marker panel had relatively low power to detect EPPs (Forsdick et al. 2021). It is in cases such as these that large marker panels of whole genome sequencing may help increase statistical power and paint a clearer picture (Taylor 2015; Kardos et al. 2015).

Landscape genetics and multi-species studies

Landscape genetics combines genetic and spatial or topographic data to understand how species move around a landscape and what features or aspects might be preventing gene flow (Manel et al. 2003). This is especially important when seeking to understand how habitat fragmentation or loss may be affecting a given species (Sunnucks 2011). Species with different dispersal abilities may be differentially affected by habitat loss, but multi-species studies examining this issue are extremely rare. In a review-style paper, Radford et al. (2021) take us through the impressive multi-year Birds in Fragmented Landscapes research programme. The project uses various genetic marker types to assess responses to habitat fragmentation in 10 different bird species of varying dispersal ability across 12 habitat squares with varying habitat degradation. This incredible breadth of work demonstrates genetic data being used effectively to answer conservation questions, and the paper gives some useful recommendations regarding habitat degradation and connectivity. The programme is a huge achievement and an illustration of the importance of multi-species, multi-habitat studies for conservation management.

Conclusion

The papers in this Emu Austral Ornithology special issue – Conservation Genetics: Showcasing Applications in Austral Birds – clearly demonstrate that genetic data can inform conservation efforts in myriad ways. From delineating conservation management units and revising taxonomy (Burbidge et al. 2021; Grosser et al. 2021; Joseph et al. 2020; Joseph et al. 2021), to examining population structure and connectivity within species (Beckmann et al. 2021; Brown et al. 2021; Lohr et al. 2020; Taylor et al. 2021; Wold et al. 2021), to informing translocation management (Bolton et al. 2021; Cowen et al. 2021; Dwyer et al. 2021; Taylor et al. 2021), to understanding better the life histories of threatened species (Forsdick et al. 2021), to using genetic data to infer past and future extinctions (Cowles et al. 2021; Grosser et al. 2021; Ramstad et al. 2021), through to landscape-level longitudinal studies across multiple species (Radford et al. 2021), we have shown that genetics is a powerful tool that should be in every conservation manager’s toolbox.

The studies presented in this issue demonstrate not only the wide breadth of austral avian conservation genetics research, but also the variety of genetic tools on offer to tackle conservation questions. Traditional tools such as mitochondrial DNA and microsatellites still have value for avian conservation studies, especially if the limitations of these tools are properly acknowledged. Newer genomic tools, such as large panels of SNPs and whole genomes, offer additional, exciting opportunities; at a basic level these tools significantly boost statistical power, but they also offer the chance to delve into regions of the genome that may be particularly important for species to adapt to an increasingly stochastic environment. With the constant increase in the number of published high-quality bird genomes (Zhang et al. 2014; Feng et al. 2020) and ongoing reductions in the cost of genomic sequencing, the capacity of genetic research to inform avian conservation is only set to increase.

In the face of exciting genomic developments, it is important to remember that conservation genetics research is at its most useful when studies are driven by a genuine conservation need rather than purely academic interest (e.g. Hogg et al. 2017). As illustrated by many of the studies in this issue, collaboration with conservation practitioners is key to producing work that can have a meaningful impact for the management of a study species. Our hope is that this special issue of Emu Austral Ornithology acts as a catalyst for new collaborations between conservation geneticists and the conservation managers tasked with declining bird species. Increasing the number of these collaborations can only improve the conservation of the birds that we all wish to see persisting well into the future.

Acknowledgements

We are grateful to all the authors who have contributed papers to this special issue, to EMU Editor in Chief Kate Buchannan for her invaluable assistance, and to Leo Joseph for helpful comments on this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).