GENETICS AND THE CONSERVATION OF WILD POPULATIONS

• The increasingly sophisticated methods for analyzing molecular variation at several levels within species provide important tools for managing endangered species. But for most managers and conservation biologists, the methods and results of molecular genetic surveys are a mystery, bordering on alchemy. This chapter provides an introduction to the main techniques in use and methods for analyzing the data, with worked examples. This will provide the basis for subsequent chapters that discuss the use of the data to make inferences about population processes and history.
• Chromosomes, proteins, microsatellites, RAPDS and DNA fingerprinting, analyses of sequence variation. Measures of molecular diversity, partitioning diversity within and among populations, phylogeography. Organelle and nuclear genes: strengths & limitations
• Estimates of genetic variation, Pi, Ho, He (call gene diversity), # alleles, Fis, etc. (?Include Fst, Rst, etc here too? - at the very least forewarn of their existence, then put in CH6).

• The aim of conservation genetics is not to conserve every genetic variant, only those that assist in continued evolution of species in their changing environment and ecological roles. Thus it is important to choose appropriate genes or surrogates for management and monitoring. The most appropriate loci are of course, those whose variation will affect lifetime fitness in the short-or long-term future, in a changing environment. Although it is difficult to specify exactly which loci are appropriate, some generalizations can be made. First, fitness traits tend to be multi-factorial - affected by multiple loci and the environment.
• Genetic architecture is the way in which multifactorial traits are controlled. This includes the number of underlying loci, their physical arrangement (ploidy, linkages), their biochemical interactions (regulatory, protein-protein, and environment-gene), and the resulting pattern of additive and non-additive interactions such as dominance and epistasis. The genetic architecture is not static, but can alter in response to mutation at any of the contributing loci, recombination, environmental changes, and random genetic changes. All of these may be quite high for multifactorial traits, especially under conditions that threatened species are likely to experience, such as periods of environmental stress or small population size.
• Natural selection can appear to act at different levels from the individual locus through to lifetime fitness. The apparent type and direction of selection may differ at these levels, even in the same system of interacting loci. There can also be selection for traits to be more or less sensitive to variation at other loci or in the environment. Limited studies suggest that there is poor correlation between variation of different types, so the choice of appropriate suites of surrogates at different levels is an important direction for conservation genetics research.
• Ideally, conservation managers would monitor and manage the genetic variance of lifetime fitness, but even this strikes three problems: first, it is difficult to analyze multifactorial genetic variation in wild populations; second, it is difficult to analyze total fitness, and finally the analysis would be restricted to the current population. The first problem may soon be alleviated by use of molecular techniques, although the current methods are restricted to populations with an extremely wide range of relatedness values; better methods may come from molecular reconstruction of wild pedigrees
• In the absence of a generally applicable way of measuring fitness and its genetic variation, there is a need for judicious choice of a suite of traits and loci to monitor, as representatives of the types of selection-related variation to be managed. There have been various suggestions about how to identify specific traits or loci for monitoring, but none have been validated. Maybe traits under strong selection could be identified by their insensitivity to environmental variation. It would also be possible to monitor variation in suites of single loci chosen for reasons such as their known selective importance or significance in metabolic networks
• Heritability is important for short-term response to selection, but may be very low for fitness related traits. Additive genetic variance or the related measure called evolvability is what conservation genetics strives to maintain, and is often high for fitness related traits, so its monitoring and maintenance is a worthwhile exercise.
• Subdivision between populations is expected to increase the effect of linkage and adaptive divergence, and the small number of studies dealing with both molecular and multifactorial characters show conflicting results.

• Even the simplest conservation actions such as a population census can be seriously hampered by incorrect diagnosis of individual sex and identity, family relationships or mating system. Many organisms have mixed reproductive strategies with varying ploidy and mixtures of sexual vs. clonal reproduction - this needs to be recognised in monitoring and management. More intensive actions such as translocations to wild or captive populations require detailed attention to these matters. Also, threatening processes have the potential to affect mating systems dramatically, or may affect certain family groups more than others. These changes can, in turn, magnify other threats.
• Molecular markers can be used to identify genetically distinct individuals and their sex This, in turn, can be used for population censuses, monitoring of sex ratio and tracking individual movements. However physical recaptures remain necessary to test error rates and provide essential information such as condition, growth rates etc.
• Highly variable markers are also used in natural populations to define parentage estimate relatedness among individuals and pedigrees and analyze the breeding system. Some aspects of population structure, such as plant mating systems, are very responsive to certain threats. This makes their molecular analysis a very good indicator of these threats, but the long-term importance of these changes is debatable, since the system itself is so labile.
• In most cases, molecular analyses are greatly aided by other ecological information, such as the ages of potential parents and offspring.

• Genetic change underpins evolution and is central to conservation The likelihood that threatening processes may alter these rates of change, highlights the importance of estimating the expected rates under different conditions. Each population, with its particular life-history, population size and other characteristics, will have a particular rate of change, which can be expressed as 1/2Ne. Ne is sometimes called the "effective population size", but this name can be misleading since Ne is a function of the population's entire biology, not just census size. As a rough approximation, Ne may be thought of as the number of individuals that are passing their alleles on to the next generation. Ne is often an order of magnitude smaller than adult population size, especially if periods of small population size ("bottlenecks") have occurred.
• Estimates of Ne iare also important to gauge that rate of change at genes affecting survival and reproduction. This is because the efficiency of selection depends on its strength, s, relative to that of drift [ i.e s > 1/Ne].
• In the same population, different genetic processes will not necessarily occur at the same rate, so there wiil be different Ne values for each estimate of genetic variation, such as inbreeding (NeI), gene diversity (NeV), and association between alleles at different loci (genotypic disequilibrium, NeD). The existence of multiple types of Ne means that conservation biologists must choose carefully which is appropriate to the particular management concerns.
• There are many ways of determining Ne and the estimate obtained often relate to different time-scales and stages of population history. Several methods can be selected to provide complementary information relevant to management.
• Current Ne can be estimated from appropriate demographic data, but often these data are difficult to obtain. There have been attempts to define Ne as a function of adult population size given for particular life history and ecology, but these methods are debated still. Estimating Ne over a deeper time-period requires more data, especially fluctuations in population size. Deeper still, Ne over thousands of generations can be estimated from gene trees; such estimates are valuable for comparison to those of current Ne, especially in recently perturbed systems.
• Ne can also be calculated from data on hypervariable genetic markers. The most obvious method is somewhat circular: to repeatedly measure genetic change, and from the rate of this change, back-calculate Ne. Although an important component of ongoing monitoring, this lacks immediate predictive power, unless molecular analyses of historical collections are possible. Therefore much attention has been given to molecular methods for Ne estimation and bottleneck detection. Especially when combined with information on demography and history from monitoring, these data can be used to estimate simultaneously both current and historical Ne, providing for more direct comparisons.
• The scope of the Ne estimation is important. All rates of change are per-generation, which requires careful definition in species with overlapping generations. Threatened populations with the same Ne but different generation lengths are likely to accumulate genetic problems at a different rate. Estimates of long-term Ne such as analyses of allele genealogies within populations, provide a perspective on changes in Ne through time. These may provide a yardstick against which current Ne and population fluctuations can be compared, with large deviations signaling a need for attention.
• The geographic scope and structure of the population(s) being managed will affect Ne also, and this will be discussed further in the next chapter.

• Wildlife managers need to be aware of the geographical scale of populations and the magnitude and nature of connectivity among populations in order to establish appropriate sampling schemes for monitoring effects of threatening processes and actions to ameliorate these.
• Gene flow differs from ecologically measured dispersal and migration in that it reflects only the net distance between birth and reproduction. Proper management of populations requires an understanding of both the ecological and genetic dimensions of dispersal.
• Differences of individual genetic profiles relative to their geographic separation carry information about local effective population size, density and dispersal distances within a continuous population
• The geographic structure of populations can, in principle, be discerned by comparing genetic divergence against geographic separation of populations, although this can vary within a species across different spatial scales and different habitat types
• A Management Unit can be defined as a genetically distinct population, typically measured by significant differences in allele frequency. This criterion identifies populations that exchange relatively few individuals and are therefore likely to be demographically independent. For animals mtDNA generally provides a particularly sensitive marker of special relevance because it reflects the behavior of females, which may differ from that of males.
• Levels of gene flow among subpopulations can be estimated from the distribution of genetic variation in populations at or near equilibrium and comparison of differently inherited genetic markers can reveal sex-biased dispersal. However, such estimates are typically imprecise and many threatened species are likely to be far from equilibrium conditions because of recent and severe reductions in population size or connectivity, so that most genetic parameters will refect historical rather than current conditions.
• Comparisons between multilocus genetic profiles of individuals and those of populations can identify birth siteand thus detect migrants even where populations are not in equilibrium. Such "assignment tests" provide a powerful way of monitoring immigration in perturbed or managed systems. Ecological methods can then be used to follow the fate of immigrants.
• If populations are undergoing local extinction and recolonization, the genetic parameters may give misleading estimates of connectivity, but with appropriate comparisons is may be possible to detect such dynamics.
• Genetic data, particularly the distribution of alleles in relation to their phylogeny (phylogeography; as revealed by DNA sequencing), can provide unique insights into long-term processes of isolation and range expansions, against which current population structure can be compared. Major differences between historical and current structures provides one criterion for prioritizing conservation actions and targeting ecological studies.
• Fragmentation of habitats may pose a significant threat to the viability of wildlife populations and the hope is that genetic data, as a complement to ecological approaches, can provide an early indication of major changes in connectivity. Whereas it is unlikely that genetic data can provide realistic estimates of connectivity in recently fragmented systems, it may be possible to detect major reductions in genetic population size and, perhaps, increases in inbreeding. Such information could be used to target intensive ecological studies and focus management strategies.
• Genetic profiles can be used to identify the origins of individuals in harvests or the relative contributions of separate management units in mixed populations. These tools can contribute significantly to harvested or migratory species.

• Detection of hybridization between distinct gene pools or species is an important tool for wildlife managers trying to gauge the effects of deliberate or inadvertent introductions on existing populations, particularly where the latter are already under threat.
• It is also important to recognise any role that the process of hybridization has played in the evolution of species complexes and in maintaining genetic diversity in small isolated populations.
• Genetic markers derived from both nuclear and organelle genes have been used extensively to investigate the extent and dynamics of hybridisation in natural populations.
• These applications are reviewed and illustrated with appropriate case studies, providing background for the discussion of effects of outbreeding in chapter 11.

Chapter 8: Biodiversity Assessment
• International conventions and national policies call for protection of biodiversity at multiple levels, including genetic diversity, but how to assess and prioritize genetic biodiversity within and across species and areas remains unclear.
• The assumption the protection of ecosystems and threatened species will de facto encompass genetic diversity does not hold where current taxonomy does not reflect evolutionary history. Genetic studies of many groups of organisms have revealed misaligned species boundaries and morphologically cryptic species. If undetected, this detracts from species-based assessments of biodiversity and monitoring and management of individual threatened species.
• Several approaches have been suggested for incorporating phylogenetic information into biodiversity valuation. One view is that we should maximise the phylogenetic breadth of species conserved; another holds that rapidly speciating lineages should have priority. This is the basis of genomic approaches to rapid biodiversity inventory. Whatever the approach adopted, molecular phylogenies can provide useful insights into long-term processes of extinction and speciation, against which current threats can be evaluated.
• How to identify and prioritize intra-specific evolutionary units for conservation is contentious. Genetic diversity can be considered along two dimensions - one related to survival and reproduction (natural selection and adaptation) and the other to historical isolation. Adaptive genetic diversity is, perhaps, best retained via protection of ecological amplitude rather than protection of specific phenotypic variants. The diversity due to historical isolation cannot be recoved if lost and should be given priority in planning to conserve genetic diversity.
• We advocate a binary approach to identifying conservation units, recognizing Evolutionarily Significant Units and, within these, Management Units. These can be defined from patterns of phylogeography and variation in allele frequencies, respectively. The former are targets for protection whereas the latter are the components that must be managed to ensure this
• Listing of geographically peripheral isolates across state or national boundaries poses a dilemma for management agencies, particularly where the same species is widespread and secure elsewhere. We argue that protection of such populations is appropriate where they are historically isolated (ESUs) or occupy environments that are unique for their species.
• The concepts developed to identify ESUs within species can be extended to conservation of habitats and areas. Molecular genetic analyses can be used to identify and, perhaps, rank, areas of habitat where there is a history of biogeographic isolation, revealed through geographically congruent patterns of phylogeography. Such rankings can identify sets of areas that maximize the representation of genetically divergent areas, and through an understanding of historical processes, also identify areas of potential evolutionary innovation. Areas of evolutionary significance can be combined with assessments of species distributions to design conservation strategies that maximize the representation of current biodiversity and also promote continuing evolution and thus biotic responses to environmental change. Within these areas it is important to retain maximum environmental variation in order to protect adaptive genetic diversity.
• Exploitation of genetic resources has achieved increased prominence and, through the Convention on Biological Diversity, has considerable ramifications for conservation and the scientific endevour that underlies it. We argue, from an evolutionary perspective, that nations should be regarded as stewards, rather than owners, of genetic resources that, thus, that a substantial proportion of revenue from exploitation of genetic resources should return to conservation and promotion of sustainable use.

• A pre-eminent concern in conservation genetics has been the loss of genetic diversity within small isolated populations and its likely impact on short term fitness and the longer-term capacity to respond to environmental change. Both of these potential impacts are controversial and this chapter reviews relevant theory and evidence from experiments in laboratory and natural environments. This chapter discusses the management of two aspects of genetic variation: gene diversity (He) and allelic diversity (K).
• Populations with higher He are expected to have a higher number of heterozygotes. These heterozygotes are expected to have higher fitness. This expectation rests on a variety of studies, mostly of wild or semi-wild populations, which usually show some advantage to heteroygotes. It is possible that a large number of studies showing no association between heterozygosity and fitness go unreported, but very few studies show a negative relationship.
• The fitness effects of heterozygosity may be sufficient to have substantial influence on short-term population persistence; the scanty data suggest that can be the case. However, there is a need to better establish the link between effects on individual fitness and population viability. This is an important area for further research.
• Long-term effects of genetic variation (He, K) are more difficult to study, but again theory suggest that more variable populations will be better able to evolve in the face of changed or fluctuating environmental conditions. There is some support for this from captive and domestic populations, as well as the phylogenetic patterns in sexual and asexual species. Both gene and allelic diversity are expected to be important in long-term evolution. However, it is not at all clear whether greater responsiveness to selection in the short-term leads to greater population persistence, as expected from theory. Again, further research is indicated.
• Aside from loss of heterozygosity, small populations are also prone to accumulation of mildly disadvantageous alleles as random processes overwhelm selection. Theory predicts that this can reduce population viability in extremely small populations or over very long periods of isolation. Direct evidence for this process is still lacking.
• Loss and maintenance of genetic variation depends the interplay between random genetic drift, mutation, recombination, mating patterns, dispersal, and other factors such as genome structure. For any combination of factors, a population is expected to approach an equilibrium level for each measure of variation, and then fluctuate about this. Most populations are probably not at equilibrium. Changed conditions will result in a new target equilibrium.
• Where conditions change as a result of threatening processes, the new equilibrium level of genetic variation may not be the optimum for short- or long-term conservation. The response to the new selective regime may be limited in either speed or total magnitude. Also there may be transitory or permanent changes in the genetic architecture during bottlenecks or other perturbations.
• Ideally, management of genetic variation will rely on early identification of problems, through monitoring not only genetic variation itself, but also surrogates such as population size, dispersal level, and rates of reproduction and survival. Other suggested predictive tools range from a focus on a single gene family (MHC) to the use of population history inferred from molecular studies, but none of these have been adequately explored for general applicability.
• If genetic problems are identified early, then reversal of obvious threats such as reduced immigration will allow the population to continue its normal process of adaptation to change.
• More serious genetic management may be required in situations where the population cannot cope with change, because it has already lost too much variation, or is too small, or otherwise vulnerable, to cope with the demographic consequences of selection. In this case, translocations between wild populations or between wild and ex-situ populations may be required [more on this in chapter 11].
• Ex-situ management may also be instituted for non-genetic reasons, such as demographic support for the wild population. The utility of this procedure depends upon the success of reintroduction(s) and the genetic quality of the reintroduced stock. Ex-situ management usually deals with only small numbers of individuals, and therefore genetic concerns are very important. Luckily, the intensive nature of ex-situ management gives considerable scope for genetic control in most species, but each stage of the process must prioritise genetic, demographic, and husbandry concerns in a different way. It is important not to lose sight of the ultimate goal of re-releasing into the wild.

• Many species have mating patterns which result in considerably more or less inbreeding than expected in a random mating finite population. Conservation biologists are concerned when a species' normal level of inbreeding is altered by threatening processes. Could this worsen the conservation outcome, especially by interaction with other genetic problems such as lowered variation between individuals (He)?
• Inbreeding and other assortative mating cannot directly alter the amount of genetic variation in the population (He); however, they increase the chance of identity by descent (IBD#1), and thus decrease heterozygosity below random mating expectations (positive Fis). Non-random mating patterns can also alter associations between alleles at multiple loci, giving significant genotypic disequilibrium.
• There is abundant evidence from domesticated species, captive breeding of wild species, and wild plant species, that inbreeding generally reduces fitness and increases the appearance of unusual traits, or the variance of traits. This inbreeding depression may be based on single or multiple loci, and it may be due to the disadvantageous effects of homozygosity for a particular allele (recessive deleterious mechanism), or to disadvantages for homozygotes of any kind (overdominance mechanism). The different mechanisms have different management implications, so it is important to note that the small number of studies have indicated that all mechanisms can be operating at different loci in a single species.
• Given that inbreeding reduces fitness, there is concern that it may adversely affect population persistence, and thus threaten short- or long-term conservation. There is some supporting evidence from wild and ex-situ populations, especially from those in stressful environments.
• Monitoring of mating systems can use an array of measures and surrogates. Even molecular measures must be subjected to scrutiny since some, such as Fis, could derive from sources other than inbreeding, which may have different conservation implications. Non-genetic surrogates such as rates of pollinator movement can also be used, but considerable research is required to show their relationship to inbreeding.
• As well as monitoring inbreeding levels, it is important to know whether any increase is associated by adverse changes to the mean and variance of survival and reproduction- inbreeding depression. It is easy to miss this association, for a number of reasons: the normal level of inbreeding for the population may not be known; unless total fitness is measured, the traits monitored may not be the ones which show depression in that population; the depression may not be evident in the studied environment, especially if it is an artificial one; and the effects of inbreeding may be cryptic until a certain threshold is crossed.
• Management of inbreeding often requires use of surrogates, such as maintenance or enhancement of normal dispersal mechanisms and Ne. Attempts to produce general rules for population size or to predict sensitivity from prior Ne or breeding system have not met with success. It has been suggested that managers could simply allowing inbreeding to occur and natural selection to purge deleterious recessive homozygotes, if the population is large enough to withstand the death and reproductive failure that selection is based upon. However, purging is not likely to be generally applicable, since the deleterious recessive mechanism is not universal, and even in cases where there has been some success at purging, there was not full recovery of pre-inbreeding fitness.
• Removal to an ex-situ facility is usually the only solution that allows direct control of mating patterns, but this is costly, and the low population size generally commits the manager to high levels of inbreeding, as well as other genetic problems. Combined with the cost, this means that ex-situ management cannot be recommended often.
• Whatever method of management is used, it is important to monitor for the resultant level of inbreeding and depression, since many studies show that it is difficult to predict which species will be more prone to depression.

• Management of interacting populations requires an understanding of both demographic and genetic processes and should be conducted in the context of prior levels of connectivity as inferred from molecular markers.
• Metapopulations may provide for evolutionary innovation, but this does not mean that unnaturally fragmented systems should be left to their fate because (i) the evolution of new adaptive forms via this "shifting balance" process is probably rare and (ii) local population extinctions are unlikely to be rescued by recolonisation.
• Outbreeding depression, a reduction in mean viability or reproduction, has commonly been raised as a concern in the conservation literature, but evidence for its generality in inter-population crosses in nature appears weak. Nonetheless, wildlife managers should be aware of the different genetic bases and manifestations of outbreeding depression when managing interacting populations. The magnitude of outbreeding depression is not generally predicted by geographic distance between populations, and like inbreeding depression, may be more apparent in stressful environments.
• Limited genetic exchange between unnaturally isolated populations can reduce the undesirable effects of inbreeding and loss of genetic variation, without impeding local adaptation. The level of managed migration needed to achieve this benefit depends on whether the immigrants are related, the ratio of effective to census population size, and extinction - colonisation dynamics of the populations concerned.
• In practice, wildlife managers should consider the trade-off between the likelihood of inbreeding vs. outbreeding depression. Outcrossing may have immediate benefits to survival and reproduction where the populations involved are inbred and can also greatly enhance levels of within population genetic diversity. Translocations for conservation purposes should be guided by historical levels and patterns of gene flow and use of inbred individuals for reintroductions should be avoided. Guidelines for mixing of populations become particularly important when in-situ and ex-situ conservation approaches are integrated.
  ***** More on this from Ch 12.
• With regard to historical processes, translocations can be conducted among MUs within ESUs, but not among ESUs because there is evidence for recent migration among the former, but not the latter. However, it remains to be determined whether difference in local adaptation or outbreeding depression within ESUs reduce viability of translocated or augmented populations. This is an area ripe for experimental studies.

• Human-induced selection and genetic modification can often be so intense as to directly affect conservation management. Impacts on natural evolutionary processes span all major contributing processes - introduction of genetic variation, drift, migration, mating system and selection. Here we focus on the first and last of these.
• Novel genetic variants introduced by humans is often more dramatic than the naturally-occuring ones. One class of genetic modification is quite deliberate, being aimed at producing a better domestic species, or improved biological control. These usually take the form of additions of multiple new alleles by artificial hybridization with a different strain or species, or insertion of an entire new locus by molecular manipulation. Also, the introduction of new species continues apace, and this opens the way for untold novel hybridizations.
• None of the mutational processes is completely controlled. Nor in general, do we know what range of phenotypes can result from interaction of novel alleles or loci with the genetic background of the host population and environment-dependent expression. In the case of hybridization, we do not know exactly what the genetic changes are. In the case of molecular manipulation, we usually do not yet have the expertise to insert the locus in the part of the genome where we can predict the way that it will function, nor to provide all the appropriate regulatory loci. The products of these rapid and somewhat random genome reorganization are usually screened in experimental conditions to eliminate those which do not have the desired new traits, or even show undesirable traits. One thing we have learnt from conservation genetics is that the benign lab environment is a poor predictor of outcomes in natural, stressful environments. In principle, this screening could be extended to include any trait which concern conservation biologists, and any environment, but the expense could be prohibitive.
• The conservation concerns from genetic modification are that the organism itself may become a pest, or that the novel genetic material may be passed on to other species, altering their conservation significance.
• It could be debated that the release of only a modified version of a species already present in the environment is less hazardous than an entirely new species. In theory, all additions to the wild should be subjected to the same controls that are applied to deliberate releases of entire new species, as in for biological control. Taking this point of view behoves us to improve the screening of new species, to the point where there are never errors like the "escape" of control agents. Precautions are particularly important where it is proposed to release the new organism or genetic material into the environment at large, as in attempts to infect pest populations with genetically modified biological control agents, or to genetically improve harvested wild populations.
• Human alteration of selection is even more noteworthy. Whenever humans activities favour one genotype at the expense of others, then there is deliberate or inadvertent artificial selection. If a high proportion of the population is affected, then this selection can result in major changes to the genetic and ecology of the species. Examples include changes in life history following selective harvests, and control programs. The more efficient the harvest or control is, then the faster will be the selection for the less harvestable or more resistant genotypes. It is sometimes stated that there cannot be buildup of resistance to certain types of control methods, but a full appreciation of the biology of the species usually shows points where genetic resistance could develop. The build-up of less-desirable genotypes can be slowed by integrating multiple methods with different selectivity.
• As well as affecting the loci under selection, such intense selection has the potential to affect other loci in two ways: by a selective sweep in which alleles at linked loci are driven to fixation, and by reducing Ne dramatically, because only a small proportion of the population survives selection each generation. Additional, side effects are expected in which selection for one phenotype will cause disadvantageous changes at genetically correlated traits. All these can have adverse effects on loci which are important for long-term evolution, which is particularly important in populations which are harvested but endangered, or those which are controlled as a pest in one part of their native range, but conserved elsewhere.
• Addition of new species or genetic material can also affect selective pressures on other species, especially in closely interacting systems like host and parasite, where coevolution may occur.
• Human activities can change the selective regimes also, as in the case of global warming and acid rains. Species which do not have appropriate genetic variants to adapt, or the ability and opportunity to move to unaffected areas, are expected to decline, as seen in notable examples in severely polluted areas. It is possible that broad swathes of conserved areas across latitudinal and altitudinal gradients would allow some species to move in response to these threats, but others may need to be artificially moved, or the pollution ameliorated at the site.

• Conservation genetics should not be seen as an abstract science removed from ecological approaches or as one making inflexible recommendations to be adopted uncritically by wildlife managers. Increasingly, efforts to conserve threatened species are guided by multidisciplinary recovery teams including both research and management perspectives. As the barriers between theory and practice are eroded, both the application and theory of conservation genetics will be improved.
• Major challenges for the future include:
   - moving from conservation of entities to process
   - putting genetics into an ecological timeframe
   - combining quantitative and molecular approaches
   - extrapolating from laboratory to natural environments - the nexus between adaptive management & cons. Genetics.
  [Return to Top]