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Threats to the future function of forested ecosystems and stability of ecosystem service provisioning due to global change have motivated climate-adaptive forest management strategies that include various forms of tree planting termed "adaptation plantings". Despite the emergence of these strategies, less is known as to how foresters and other natural resource managers perceive or are engaged with adaptation plantings like forest assisted migration (FAM). This knowledge gap is most pronounced in regions like New England and the North Central US (hereafter, the Northeastern US) where tree planting is less common but expected to be an important forest management tool for adaptation. To address this, we surveyed 33 natural resource managers in this region actively engaged in climate change adaptation (i.e., early adopters of the practice) to assess how tree planting for adaptation is currently being pursued against the perceived barriers, opportunities, and potential future engagement with the strategy. Survey respondents overwhelmingly (93.5%) forecast increases in the future use of adaptation plantings in their work in the region, attributed to increased awareness, acceptance, and interest in the practice. Respondents expressed notable interest in strategies related to diversification and most types of FAM (e.g., assisted population expansion and assisted range expansion), but hesitancy to engage with more contentious planting types like afforestation or FAM linked to the long-distance translocation of exotic species (e.g., assisted species migration). Although examples of local enrichment plantings (i.e., non-FAM) proliferate, nineteen of the top twenty most common tree genera planted contain at least one example of FAM in the study region. The most notable barriers reported were themed as 1) biotic and abiotic, 2) information and material, and 3) policy, social, and economic factors. While most respondents report difficulty obtaining adequate planting material from nurseries (i.e., seedlings), over 80% placed orders shortly before planting (< 1 year) which likely generates difficulty in sourcing seedlings suited for a specific site and future range of environmental conditions. Although this study is limited by focusing on subset of natural resource managers who are early adopters of climate change adaptation within the region, valuable inferences into the barriers and trends are possible from this population serving on the front lines of forest adaptation. Together, these results from early adopters suggest a potentially growing need for allocating resources that engage forest stewards in adaptation planning and serve to refine policy, financing, and management practices to support this adaptation strategy in this region and beyond. [ABSTRACT FROM AUTHOR]

As the Anthropocene tightens its grip on the world, forests are facing escalating disturbance rates, tree mortality, degradation and risks of catastrophic collapses. A popular and controversial proposition is to enhance forests' response diversity by adding novel tree species with missing functional traits through forest assisted migration (FAM). Beyond tests of the survival and growth of southern species or provenances in colder regions and studies of the socio-ecological challenges facing FAM, little interest has been paid to the silvicultural system for FAM implementation. Yet, the topic could influence its biological success, social acceptability, and economic feasibility. For example, southern light-intolerant tree species introduced into northern uneven-aged forests may experience a lack of light availability. Likewise, implementing FAM in clearcuts raises social acceptability issues. The patch-cut system combines advantages of even- and uneven-aged systems useful for FAM; however, perhaps due to the difficulty of its operationalization, it is rarely used. We propose a new way to implement the patch-cut system, enabling from the get-go to plan the location and timing of treatment of each patch in a stand. We discuss the advantages that this revisited patch-cut system presents for FAM: (i) the testing of various planting environments, (ii) easy monitoring in an adaptative management context where each patch is a replicate of a repeated-measure experiment and (iii) low intensity planting for efficient future dispersion of species adapted to a changing climate. We end with a call for the development of an international network of FAM trials within the revised patch-cut system. [ABSTRACT FROM AUTHOR]

Conservation translocations are widely used to recover threatened species, but can pose risks to recipient ecosystems, particularly in the case of conservation introductions. Because of limited data and uncertainty, risk assessments for such projects often rely on extrapolated evidence and expert opinion, further complicating decision making. The Environmental Impact Classification for Alien Taxa (EICAT) serves to classify the realised impacts of invasive species. We developed a protocol combining EICAT and formal expert elicitation to predict these impacts. We applied our protocol to the extinct-in-the-wild sihek (Guam kingfisher; Todiramphus cinnamominus), for which introduction outside the known historical range is being considered. We elicited from multiple experts probability estimates of impact levels across four impact mechanisms and five candidate release sites. We aggregated estimates using simulation-based and Bayesian approaches, with and without accounting for expert confidence. Experts generally agreed that sihek introduction might impact the recipient ecosystem through predation, competition, and disease, although they disagreed about the likely impact levels. Releases to Palmyra Atoll were considered to pose the lowest risk across candidate sites, so this site was selected for further detailed ecological assessments and risk mitigation efforts. EICAT, with its standardized impact mechanisms and definitions, helped reduce the linguistic uncertainty and subjectivity common to expert-based assessments. Expressing judgments as probabilities allowed us to evaluate uncertainty transparently and to assess the weight of expert confidence on the overall risk estimation. Formal quantitative elicitation and aggregation then allowed a transparent evaluation of results, facilitating communication with stakeholders and decision-makers. [ABSTRACT FROM AUTHOR]

Salt marshes pose challenges for the birds that inhabit them, including high rates of nest flooding, tipping, and predation. The impacts of rising sea levels and invasive species further exacerbate these challenges. To assess the urgency of conservation and adequacy of new actions, researchers and wildlife managers may use population viability analyses (PVAs) to identify population trends and major threats. We conducted PVA for Formicivora acutirostris, which is a threatened neotropical bird species endemic to salt marshes. We studied the species' demography in different sectors of an estuary in southern Brazil from 2006 to 2023 and estimated the sex ratio, longevity, productivity, first-year survival, and mortality rates. For a 133-year period, starting in 1990, we modeled four scenarios: (1) pessimistic and (2) optimistic scenarios, including the worst and best values for the parameters; (3) a baseline scenario, with intermediate values; and (4) scenarios under conservation management, with increased recruitment and/or habitat preservation. Projections indicated population decline for all assessment scenarios, with a 100% probability of extinction by 2054 in the pessimistic scenario and no extinction in the optimistic scenario. The conservation scenarios indicated population stability with 16% improvement in productivity, 10% improvement in first-year survival, and stable carrying capacity. The disjunct distribution of the species, with remnants concentrated in a broad interface with arboreal habitats, may seal the population decline by increasing nest predation. The species should be considered conservation dependent, and we recommend assisted colonization, predator control, habitat recovery, and ex situ conservation. [ABSTRACT FROM AUTHOR]

Threats to the future function of forested ecosystems and stability of ecosystem service provisioning due to global change have motivated climate-adaptive forest management strategies that include various forms of tree planting termed “adaptation plantings”. Despite the emergence of these strategies, less is known as to how foresters and other natural resource managers perceive or are engaged with adaptation plantings like forest assisted migration (FAM). This knowledge gap is most pronounced in regions like New England and the North Central US (hereafter, the Northeastern US) where tree planting is less common but expected to be an important forest management tool for adaptation. To address this, we surveyed 33 natural resource managers in this region actively engaged in climate change adaptation (i.e., early adopters of the practice) to assess how tree planting for adaptation is currently being pursued against the perceived barriers, opportunities, and potential future engagement with the strategy. Survey respondents overwhelmingly (93.5%) forecast increases in the future use of adaptation plantings in their work in the region, attributed to increased awareness, acceptance, and interest in the practice. Respondents expressed notable interest in strategies related to diversification and most types of FAM (e.g., assisted population expansion and assisted range expansion), but hesitancy to engage with more contentious planting types like afforestation or FAM linked to the long-distance translocation of exotic species (e.g., assisted species migration). Although examples of local enrichment plantings (i.e., non-FAM) proliferate, nineteen of the top twenty most common tree genera planted contain at least one example of FAM in the study region. The most notable barriers reported were themed as 1) biotic and abiotic, 2) information and material, and 3) policy, social, and economic factors. While most respondents report difficulty obtaining adequate planting material from nurseries (i.e., seedlings), over 80% placed orders shortly before planting (< 1 year) which likely generates difficulty in sourcing seedlings suited for a specific site and future range of environmental conditions. Although this study is limited by focusing on subset of natural resource managers who are early adopters of climate change adaptation within the region, valuable inferences into the barriers and trends are possible from this population serving on the front lines of forest adaptation. Together, these results from early adopters suggest a potentially growing need for allocating resources that engage forest stewards in adaptation planning and serve to refine policy, financing, and management practices to support this adaptation strategy in this region and beyond.

As the Anthropocene tightens its grip on the world, forests are facing escalating disturbance rates, tree mortality, degradation and risks of catastrophic collapses. A popular and controversial proposition is to enhance forests’ response diversity by adding novel tree species with missing functional traits through forest assisted migration (FAM). Beyond tests of the survival and growth of southern species or provenances in colder regions and studies of the socio-ecological challenges facing FAM, little interest has been paid to the silvicultural system for FAM implementation. Yet, the topic could influence its biological success, social acceptability, and economic feasibility. For example, southern light-intolerant tree species introduced into northern uneven-aged forests may experience a lack of light availability. Likewise, implementing FAM in clearcuts raises social acceptability issues. The patch-cut system combines advantages of even- and uneven-aged systems useful for FAM; however, perhaps due to the difficulty of its operationalization, it is rarely used. We propose a new way to implement the patch-cut system, enabling from the get-go to plan the location and timing of treatment of each patch in a stand. We discuss the advantages that this revisited patch-cut system presents for FAM: (i) the testing of various planting environments, (ii) easy monitoring in an adaptative management context where each patch is a replicate of a repeated-measure experiment and (iii) low intensity planting for efficient future dispersion of species adapted to a changing climate. We end with a call for the development of an international network of FAM trials within the revised patch-cut system.

Assisted colonization to locations predicted to remain climatically suitable in the future is increasingly necessary to mitigate climate change effects in ectotherms such as reptiles. However, these future‐suitable locations are often currently cooler than those from which individuals are sourced. While species‐wide paradigms prevail, responses to thermal regimes may vary across a species range, affecting daily activity, colonization and survival in a new environment. Additionally, hydro‐regulatory behaviours are severely understudied, despite the need for understanding trade‐offs between thermoregulation and hydro‐regulation for successful assisted colonization strategies. We investigated behavioural responses to temperature and relative humidity in two latitudinally distinct lineages of pygmy bluetongue (Tiliqua adelaidensis), a cryptic, burrow‐dwelling endangered lizard, in the Mid‐North of South Australia. From spring 2020 to autumn 2021 we took monthly field‐based approach distance and behavioural footage at the source locations and at a southerly translocation site. Behaviours were matched to site‐specific microclimate data prior to principal component and generalized linear mixed model analysis. We found lineage differences in behaviour that persisted after translocation; southern lineage lizards showed significantly less daily activity and were active at lower temperatures and higher humidity than northern lineage lizards. Southern lineage lizards allowed a human observer to approach closer as base‐of‐burrow humidity increased, while northern lineage lizards were quicker to retreat into burrows, at both source and translocation sites. Novel, non‐invasive field‐based activity curves successfully identified lineage differences in humidity and temperature ranges for surface activity, implying environmental preferences of target populations that were reinforced by the models. Specifically, we found evidence for thermoregulation and adaptation/acclimation to higher temperatures in northern lizards and hydroregulation and adaptation/acclimation to cooler, more humid conditions in southern lizards. The limited behavioural plasticity shown by translocated individuals over the season demonstrates the importance of understanding lineage‐level behaviours, hydro‐regulation, and micro‐climate when selecting individuals for assisted colonization. [ABSTRACT FROM AUTHOR]

Objective: Translocations have increased in recent years to aid in species recovery efforts. This includes translocations outside of species' historical distribution, where threats are less severe. One candidate species for translocation is the Bull Trout Salvelinus confluentus, but few examples of successful translocations (re-establishment or range expansion) have been documented. Here, we describe an example in which 63 Bull Trout were translocated in 1987 to establish a population in fishless Marie Lake, Alberta. Methods: The translocation was monitored through multiple sampling events over the course of 33 years. Sampling techniques included backpack electrofishing, angling, and water quality and habitat assessments. Result: A population estimate suggested that Bull Trout increased by at least fourfold over the first 12 years; fish reached large sizes (692 mm fork length) and old ages (13 years), and the population had multiple age-and length-classes, including juveniles. Bull Trout also had become established within at least 13 km of river outside of Marie Lake by 2019. Conclusion: Although a naturally reproducing population of this at-risk species was established, numerous factors were not considered within this translocation initiative. Most importantly, nonadfluvial Bull Trout from a disparate source population located about 4000 river kilometers away were used for the translocation. Our case study represents a rare example of a successful Bull Trout translocation and highlights considerations that should occur prior to future translocations that are intended to aid in species recovery and preservation. [ABSTRACT FROM AUTHOR]

Laysan (Phoebastria immutabilis) and Black-footed Albatrosses (P. nigripes) nest primarily on low-lying atolls in the Northwestern Hawaiian Islands that are threatened by inundation from sea level rise and increasing storm surge associated with climate change. Restoration or creation of breeding colonies on higher islands is among the highest priority conservation actions for these species. A previous structured decision-making analysis identified the California Channel Islands as a possible restoration site for Black-footed Albatross. The California Current is part of the natural foraging ranges of Laysan and Blackfooted albatrosses. Archaeological evidence indicates both species were present in the California Channel Islands prehistorically, yet neither currently nests in the Channel Islands. We assessed the feasibility of creating albatross breeding colonies in the Channel Islands using social attraction and translocation, and the suitability of each island. We used a risk analysis framework developed for the U.S. National Park Service to evaluate the potential ecological risks of this action. Creating an albatross colony in the Channel Islands is feasible using available methods. Santa Barbara and San Nicolas islands would be most suitable for albatross. Social attraction is less expensive and might be effective for creating a Laysan Albatross colony because that species is already visiting some islands. Translocation would be necessary to create a Black-footed Albatross colony. The risks associated with attempting to establish albatross breeding colonies in the Channel Islands were deemed to be generally low, but the risk of no action is high to these albatrosses. This can be a useful assisted colonization case study that can inform decisions by land managers and agencies regarding conservation of North Pacific albatrosses and other species. [ABSTRACT FROM AUTHOR]

Laysan (Phoebastria immutabilis) and Black-footed Albatrosses (P. nigripes) nest primarily on low-lying atolls in the Northwestern Hawaiian Islands that are threatened by inundation from sea level rise and increasing storm surge associated with climate change. Restoration or creation of breeding colonies on higher islands is among the highest priority conservation actions for these species. A previous structured decision-making analysis identified the California Channel Islands as a possible restoration site for Black-footed Albatross. The California Current is part of the natural foraging ranges of Laysan and Black-footed albatrosses. Archaeological evidence indicates both species were present in the California Channel Islands prehistorically, yet neither currently nests in the Channel Islands. We assessed the feasibility of creating albatross breeding colonies in the Channel Islands using social attraction and translocation, and the suitability of each island. We used a risk analysis framework developed for the U.S. National Park Service to evaluate the potential ecological risks of this action. Creating an albatross colony in the Channel Islands is feasible using available methods. Santa Barbara and San Nicolas islands would be most suitable for albatross. Social attraction is less expensive and might be effective for creating a Laysan Albatross colony because that species is already visiting some islands. Translocation would be necessary to create a Black-footed Albatross colony. The risks associated with attempting to establish albatross breeding colonies in the Channel Islands were deemed to be generally low, but the risk of no action is high to these albatrosses. This can be a useful assisted colonization case study that can inform decisions by land managers and agencies regarding conservation of North Pacific albatrosses and other species.

• Ensemble modelling was utilized to determine potential suitable habitat range of Dactylorhiza hatagirea in Himachal Pradesh. • Ensemble of 08 different models and 05 GCMs was utilised to determine suitable future areas by years 2050 and 2070. • Suitable habitat range of D. hatagirea would be reduced by years 2050 and 2070, with conducive conditions towards east. • As per IUCN criterion A3(c), it will lose more than 30% of its current suitable habitat, can be categorized as Vulnerable. • Assisted colonization efforts in up to 7.39 new cells (2×2 km2 size) are required to exclude it from threat category. Species distributions models (SDMs) are an indispensable and important tool for predicting suitable habitats and projecting the impacts of future climate change on habitat distribution of species, particularly the threatened species. Amongst such species, Dactylorhiza hatagirea (D.Don) Soo is a threatened, medicinal orchid endemic to Himalaya. In the present study, we utilized ensemble modelling to identify the current potential suitable habitats and predict the impacts of future climate change on the distributional range of D. hatagirea in Himachal Pradesh, an Indian State in Western Himalaya. An ensemble of eight different model was run on non-collinear bioclimatic and topographic variables to predict its current potential distribution. A further ensemble of five global circulation models, focusing on four representative concentration pathways, was utilised to select the suitable habitats in future, for the years 2050 and 2070. The main bioclimatic variables influencing the predictions of potential distribution of D. hatagirea were Mean Temperature of Warmest Quarter (Bio10), Isothermality (Bio3), Mean Temperature of Wettest Quarter (Bio8), Slope, Precipitation Seasonality (Bio15) and Mean Diurnal Range (Bio2). The results of ensemble model revealed that, under present climatic conditions, the potential current suitable habitats of D. hatagirea comprises of only 0.09% of the study region. The model predicted that compared to the current distribution, the highly suitable habitats, under various future climate scenarios, would be significantly reduced by 25.34% to 56.34% and from 22.54% to 38.03% by the years 2050 and 2070 respectively. Our study also showed that the centroid of suitable habitats of D. hatagirea will shift towards eastern side of Himachal Pradesh. As per IUCN range loss criterion A3(c), D. hatagirea would lose more than 30% of its currently occupied suitable habitat, and this can be categorized as 'Vulnerable'. Therefore, an assisted colonization (AC) would be required in 0.21 to 5.98 and 0.56 to 7.39 new cells (each of grid size 2×2 km2) for the years 2050 and 2070 respectively, to halt the range loss below the threshold of 30% and shift it to the 'Least Concern' category. Further, it was found that the availability of suitable cells within existing network of protected areas (PAs) in the region are adequate and could be a better alternative to achieve conservation goals through AC. In the present study, we found that the habitats of D. hatagirea in western Himalaya are extremely vulnerable to future shifts and alterations in the climate patterns. The findings from the present study, thus, could be utilized to alleviate the threats to the survival of populations of this species by carrying out activities such as protecting the habitats, studying the unexplored populations, re-wilding and AC programmes within the PAs, for planning of conservation and management strategies. [ABSTRACT FROM AUTHOR]

Macroinvertebrate assemblages often remain depauperate in physically restored urban streams despite efforts to improve habitat conditions and increase species abundance and diversity. The lack of biological recovery may be due to a lack of a natural, nearby source of colonists, and this has inspired researchers and practitioners to reintroduce macroinvertebrates in otherwise restored urban streams to jump start the recovery process. However, without standardized guidelines that describe reintroduction best practices, some reintroduction programs may create additional problems (e.g., disease spread, genetic homogenization, population loss). To reduce these risks and limit a potential waste of resources, a cautionary approach is warranted. In this paper we summarize current stream reintroduction knowledge and detail best practices for aquatic macroinvertebrate reintroduction in restored urban streams. We provide criteria that managers can use to determine whether reintroduction is appropriate and demonstrate how researchers can use reintroduction as a tool to test hypotheses regarding factors limiting recolonization. We provide guidance for how to set clear reintroduction goals, select donor sites, determine the number of organisms required, establish reintroduction frequency and timing, and overcome challenges associated with monitoring. This framework can help managers create more successful reintroduction programs that can benefit urban stream restoration. [ABSTRACT FROM AUTHOR]

The U.S. Tropical Pacific (USTP) is a globally important area for seabirds with tens of millions of individuals of 32 species breeding in the region. The two greatest threats to breeding seabirds in the USTP are inundation of colonies caused by global climate change and non-native predators. We assessed the status of seabird species breeding in the USTP and which species would benefit most from restoration activities. We scored each species for nine criteria that reflected their extinction risk and vulnerability to climate change and invasive predators, then summed the scores of all criteria to obtain an overall score and ranked the species in terms of overall conservation need. The top five species at risk (in order) were Hawaiian Petrel (Pterodroma sandwichensis), Newell's Shearwater (Puffinus newelli), Polynesian Storm-Petrel (Nesofregetta fuliginosa), Phoenix Petrel (Pterodroma alba), and Black-footed Albatross (Phoebastria nigripes). We also assessed 86 locations in the USTP as potential source and restoration sites for seabirds to mitigate the impacts of sea level rise and invasive predators. Some restoration actions are underway for three of the top five species in the USTP, but more actions are needed. Two of the top species (Polynesian Storm-petrel and Phoenix Petrel) occur primarily outside the USTP. Actions within the USTP are needed to complement existing conservation measures underway elsewhere in the Pacific and should be prioritized for future management actions. [ABSTRACT FROM AUTHOR]

The negative impact of climate change on biodiversity will continue to escalate rapidly. While some species will naturally migrate to more suitable areas or adapt to the new climatic environmental conditions in different fashions, for others doing so may prove to be problematic or impossible. Against this backdrop, scientists and environmentalists have proposed implementing plans for Assisted Migration (AM)—meaning the translocation of plants and animals to areas outside their natural habitats to conserve their species under the new emerging climatic conditions. This article seeks to identify legal approaches towards AM considering not only possible benefits from using this tool but also a necessity to minimize related risks. With regard to its stated purpose, this article also compares legal and policy documents relevant to AM issues from the United States, Australia, and the European Union. In conclusion, we have found, and this article shows, that while existing legal and policy documents leave room for manoeuvreing in regard to climate-related translocations and even sometimes explicitly mention AM as a possible tool for conservation, there exists a need for the further development of concrete legal mechanisms and their balancing with the predominant ideas and goals brought about by the necessity to protect native biota. [ABSTRACT FROM AUTHOR]

Conservation introductions to islands and fenced enclosures are increasing as in situ mitigations fail to keep pace with population declines. Few studies consider the potential loss of genetic diversity and increased inbreeding if released individuals breed disproportionately. As funding is limited and post‐release monitoring expensive for conservation programs, understanding how sampling effort influences estimates of reproductive variance is useful. To investigate this relationship, we used a well‐studied population of Tasmanian devils (Sarcophilus harrisii) introduced to Maria Island, Tasmania, Australia. Pedigree reconstruction based on molecular data revealed high variance in number of offspring per breeder and high proportions of unsuccessful individuals. Computational subsampling of 20%, 40%, 60%, and 80% of observed offspring resulted in inaccurate estimates of reproductive variance compared to the pedigree reconstructed with all sampled individuals. With decreased sampling effort, the proportion of inferred unsuccessful individuals was overestimated and the variance in number of offspring per breeder was underestimated. To accurately estimate reproductive variance, we recommend sampling as many individuals as logistically possible during the early stages of population establishment. Further, we recommend careful selection of colonizing individuals as they may be disproportionately represented in subsequent generations. Within the conservation management context, our results highlight important considerations for sample collection and post‐release monitoring during population establishment. [ABSTRACT FROM AUTHOR]

Climate change threatens the long‐term survival of highly fragmented habitats such as North American tallgrass prairie. De novo plantings into former agricultural sites can contribute to efforts to conserve prairie biodiversity, but past planting practice (including our own) has focused on the use of local species and genotypes. Climate change makes this "local‐only" practice obsolete because of rapidly shifting species' ranges. We propose that new prairie plantings incorporate assisted migration at the community level; all species and genotypes that are viable in the changed climate and potentially could reach the site in an unfragmented landscape should be considered for inclusion. Selecting and sourcing species for climate‐appropriate restorations is possible with minimal additional cost or expertise. Based on best‐available estimates of current and future climate, species richness of future prairie plantings at our Minnesota study site could be increased by over one‐third (26 new species). Potential risks to such extensive use of assisted migration are offset by the drastic conservation challenge of highly fragmented communities under climate change. [ABSTRACT FROM AUTHOR]

The natural habitat of the western swamp turtle (Pseudemydura umbrina Siebenrock, 1901) – the ephemeral, winter wet swamps north of Perth, Australia – is in danger owing to climate change and habitat fragmentation. The decline in rainfall in this area over the last five decades is predicted to continue, shortening the annual activity period for the turtles and potentially shifting their optimal climate zone to the south.Assisted colonization to wetlands in the cooler far south west of the state is one management response. As a contribution to such a measure, the diversity and abundance of food resources and consumption by turtles were evaluated at two potential and one existing colonization site.Thirty‐five captive‐bred juvenile P. umbrina were temporarily released into three sites: Moore River Nature Reserve north of Perth (into which the species had already been successfully translocated) and Meerup and East Augusta in the cooler far south of Western Australia.Food resources were assessed using sweep nets to sample invertebrates on two occasions at each wetland. Separate samples were collected for biomass determination and for assessing invertebrate diversity. Feeding by turtles was assessed by stomach flushing.Neither biomass nor biodiversity differed significantly between the southern sites and the reference site north of Perth. Stomach contents varied greatly, from 0 to 62 animals per turtle. The main prey items were beetles, ostracods, isopods and tadpoles.Each candidate wetland provided adequate food resources, indicating that assisted colonization to the cooler south coast of Western Australia has the potential to become a reasonable conservation tool to ensure the long‐term survival of P. umbrina. [ABSTRACT FROM AUTHOR]

Assisted migration is a controversial conservation measure that aims to protect threatened species by moving part of their population outside its natural range. Although this could save species from extinction, it also introduces a range of risks. The magnitude of the threat to recipient ecosystems has not been investigated quantitatively, despite being the most common criticism leveled at the action. We used an ensemble modeling framework to estimate the risks of assisted migration to existing species within ecosystems. With this approach, we calculated the consequences of an assisted migration project across a very large combination of translocated species and recipient ecosystems. We predicted the probability of a successful assisted migration and the number of local extinctions would result from establishment of the translocated species. Using an ensemble of 1.5×106 simulated 15‐species recipient ecosystems, we estimated that translocated species will successfully establish in 83% of cases if introduced to stable, high‐quality habitats. However, assisted migration projects were estimated to cause an average of 0.6 extinctions and 5% of successful translocations triggered 4 or more local extinctions. Quantifying the impacts to species within recipient ecosystems is critical to help managers weigh the benefits and negative consequences of assisted migration. Article Impact Statement: Assisted migration is controversial conservation initiative because its effects on recipient ecosystems are not easily predicted. [ABSTRACT FROM AUTHOR]

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Abstract The intentional introduction of native cold‐water trout into high‐elevation fishless lakes has been considered a tool to build resilience to climate change (i.e., assisted colonization); however, ecological impacts on recipient communities are understudied. The purpose of this study was to inform native cold‐water trout recovery managers by assessing potential consequences of translocating a regionally native trout (westslope cutthroat trout; Oncorhynchus clarkii lewisi) into fishless mountain lakes. This study compared littoral benthic invertebrate richness, diversity, community structure and abundance between three groups of lakes (fishless, native trout, nonnative trout) in the Canadian Rocky Mountains. While richness and diversity were preserved across all lake groups, other lines of evidence suggested that the introduction of native westslope cutthroat trout into fishless lakes can alter littoral benthic invertebrate communities in similar ways as nonnative brook trout (Salvelinus fontinalis). The community structure of cutthroat trout lakes resembled brook trout lakes compared to that of fishless lakes. For example, both trout‐lake groups contained a lower density of free‐swimming ameletid mayflies and a higher density of certain burrowing taxa. Risk assessments for trout‐recovery actions should consider the potential for collateral damage to recipient invertebrate communities. Future research should identify possible cascading trophic effects on species subsidized by invertebrate prey.

The intentional introduction of native cold‐water trout into high‐elevation fishless lakes has been considered a tool to build resilience to climate change (i.e., assisted colonization); however, ecological impacts on recipient communities are understudied. The purpose of this study was to inform native cold‐water trout recovery managers by assessing potential consequences of translocating a regionally native trout (westslope cutthroat trout; Oncorhynchus clarkii lewisi) into fishless mountain lakes. This study compared littoral benthic invertebrate richness, diversity, community structure and abundance between three groups of lakes (fishless, native trout, nonnative trout) in the Canadian Rocky Mountains. While richness and diversity were preserved across all lake groups, other lines of evidence suggested that the introduction of native westslope cutthroat trout into fishless lakes can alter littoral benthic invertebrate communities in similar ways as nonnative brook trout (Salvelinus fontinalis). The community structure of cutthroat trout lakes resembled brook trout lakes compared to that of fishless lakes. For example, both trout‐lake groups contained a lower density of free‐swimming ameletid mayflies and a higher density of certain burrowing taxa. Risk assessments for trout‐recovery actions should consider the potential for collateral damage to recipient invertebrate communities. Future research should identify possible cascading trophic effects on species subsidized by invertebrate prey. [ABSTRACT FROM AUTHOR]

Biodiversity decline and genetic erosion are among the most challenging conservation issues. Genetic admixture, the mixing of two or more genetically differentiated populations, can increase genetic diversity of admixed individuals. However, genetic admixture for conservation purposes is rare due to concerns over outbreeding depression, loss of local adaptations and scepticism regarding the benefits of mixing populations. We used an introduced population of Tasmanian devils Sarcophilus harrisii descended from two genetically differentiated source populations to illustrate the benefits of genetic admixture for translocation programmes. Devils are endangered due to an infectious cancer causing 80% population declines across their range since disease emergence in 1996. Devil populations are known to be structured on an east‐west cline across Tasmania. As part of their conservation management, devils were introduced to Maria Island, Tasmania in an assisted colonization in 2012 with supplementations in 2013 and 2017. Of the released individuals (N = 34), 23 were western (13M; 10F), four were eastern (4F) and seven were of mixed origin (2M; 5F). The genetic composition of devils born on Maria Island (N = 185) was examined using 927 single nucleotide polymorphism loci. Using a reconstructed pedigree for each individual, we examined the proportion of founding origin (east, west or mixed) and used Shannon's Diversity Index to quantify the evenness of founder origin. Individuals with mixed origins (N = 102) had higher genetic diversity than purebred individuals (N = 83), and increased evenness of founder origin was positively correlated with genetic diversity. Increased genetic diversity had no influence on reproductive success. For a genetically depauperate species, mixing individuals descended from differentiated populations, resulted in increased diversity in subsequent generations. This finding permits conservation managers to select individuals for translocation that produce offspring with higher genetic diversity, creating high‐diversity source populations that can be used when augmenting other declining wild populations. [ABSTRACT FROM AUTHOR]

Exploitative competition implies an indirect interaction in which a resource exploited by one species is not available for another; e.g., when species share diet or habitat. It plays a key role in community structure and dynamics. Here we evaluated the niche overlap between the exotic aoudad (Ammotragus lervia) and the native Iberian ibex (Capra pyrenaica) where the species coexist in the Iberian Peninsula, along two main dimensions, the trophic niche and the environmental niche. Then we assessed the spatial segregation of the species. We expected that if a niche overlap was high, competition could drive spatial segregation to allow co-existence. We analyzed their trophic niche overlap by using the content of stable isotopes δ15N and δ13C in the hair of both species. To establish environmental niche competition, we compared the similarity in their habitat, estimated by environmental niche models based on the fine-scale presence records of each species obtained from field surveys. To test if spatial segregation occurred, we analyzed both species' co-occurrence. Our results indicated that both species shared a similar trophic niche measured by stable isotopes, both species showed a similar distribution of suitable areas, and that both species' environmental niches were more similar than expected. Finally, a negative spatial association was found between the aoudad and Iberian ibex. These results reveal that both species are ecologically similar and suggest that fine-scale spatial segregation might have favoured their co-existence in semiarid Mediterranean mountains. Our results show that integrating information on trophic and environmental niche overlap with fine scale spatial distribution might improve the study of competitive interactions among wild ungulates. [ABSTRACT FROM AUTHOR]

Peat‐forming wetlands, particularly floating fens that form the initial stages of these ecosystems, are declining globally due to excavation, dehydration and eutrophication. Restoration typically involves reestablishment of early‐successional open‐water stages, with oligotrophic conditions that are characteristic for these systems. However, restoration success is notoriously limited. A potential improvement may be to initiate succession by reintroducing of target plant species. Knowledge is therefore needed on (a) which plant functional groups should be re‐introduced to stimulate fen formation; and (b) how to manage nutrient levels during restoration, considering that plant growth may be slow in oligotrophic conditions.We hypothesized that increasing functional diversity of introduced species would stimulate the formation of peat‐forming target communities, their biomass accumulation and expansion onto open water. We also hypothesized that nutrient availability would mediate the relative contribution of specific functional groups to these effects. We investigated this in 36 artificial outdoor ponds by manipulating plant functional diversity (clonal dominants, clonal stress‐tolerators and interstitials) on constructed rafts with fen‐forming communities, and subjected these to a range of nutrient loadings over 2 years.Increasing functional diversity as well as increasing nutrient loadings had stimulating effects on plant biomass accumulation, cover formation and rhizome growth onto open water. Both complementarity (due to niche partitioning or facilitation) and selection effects were mechanisms underlying the diversity effect, with a constant relative importance over the entire range of nutrient availabilities. Different functional groups were important for biomass production at different nutrient availabilities. Rhizome formation by clonal stress‐tolerators contributed disproportionately to open water colonization, identifying this functional group as key across all nutrient levels.Synthesis and applications. Restoration of floating fen communities can be stimulated during the first 2 years by introducing a high functional diversity of plant species. These include fast‐growing clonal species, clonal stress‐tolerators and interstitials, which facilitate each other. Restoration is dependent on the presence of clonal stress‐tolerators such as Calla palustris, Comarum palustre and Menyanthes trifoliata for expansion onto the open water. Furthermore, restoration can start under a wide range of water nutrient levels, including eutrophic conditions. Restoration of floating fen communities can be stimulated during the first 2 years by introducing a high functional diversity of plant species. These include fast‐growing clonal species, clonal stress‐tolerators and interstitials, which facilitate each other. Restoration is dependent on the presence of clonal stress‐tolerators such as Calla palustris, Comarum palustre and Menyanthes trifoliata for expansion onto the open water. Furthermore, restoration can start under a wide range of water nutrient levels, including eutrophic conditions. [ABSTRACT FROM AUTHOR]

Anthropogenic climate change represents a wicked problem, both for the Earth's natural systems and for biodiversity conservation law and policy. Legal frameworks for conservation have a critical role to play in helping species and ecosystems to adapt as the climate changes. However, they are currently poorly equipped to regulate adaptation strategies that demand high levels of human intervention. This article investigates law and policy for conservation introductions, which involve relocating species outside their historical habitat. It takes as a case study Australian law on conservation introductions, demonstrating theoretical and practical legal hurdles to these strategies at international, national and subnational levels. The article argues that existing legal mechanisms may be repurposed, in some cases, to better regulate conservation introduction projects. However, new legal mechanisms are also needed, and soon, to effectively conserve species and ecosystems in a period of unprecedented ecological change. [ABSTRACT FROM AUTHOR]

Debate about climate change adaptation for biodiversity, and the ethics and consequences of assisted colonization in particular, has polarized professional opinion but the views of the wider community are unknown. We tested four hypotheses about the acceptability of adaptation strategies among a sample of the Australian general public using a combination of direct questions and a choice experiment. We found that (1) among the 80% who wanted extinction avoided, increased in situ management of wild populations was preferred to captive breeding or assisted colonization, (2) preferences for adaptation strategies were not explained by gender, income, education or knowledge about birds, (3) genetically distinctive taxa were not actively preferred, (4) > 60% of respondents were content for conservation managers to make decisions about strategies rather than local communities or the general public. The results provide Australian policy makers with a mandate to bolster efforts to retain existing populations but suggest that assisted colonization and captive breeding could be accepted if essential. [ABSTRACT FROM PUBLISHER]

Translocations are a tool to restore populations of threatened plant species that are being widely used. However, these techniques are not without risks and require rigorous protocols to carry them out and for their subsequent monitoring. In translocation projects, hybridization with other species is one of the most important risks and may threaten the survival of the species we want to protect. Here we present the case of Helosciadium bermejoi (L. Llorens) Popper and M.F. Watson, a Critically Endangered plant from the island of Menorca (Western Mediterranean). It occurs only in one locality and has been introduced to three new locations during recent years according to its Recovery Plan (2008). Recently, intermediate forms between the endangered species and a native congener, Helosciadium nodiflorum (L.) Koch, have been detected. The aims of this study were (i) to elucidate whether these plants originated through a hybridization event and (ii) to provide information about the current conservation status of the species. Exhaustive monitoring of all subpopulations (number of patches and area of occupancy) was performed from September 2015 to June 2016, and the rDNA ITS region and cpDNA rps16-trnK intergenic spacer region were sequenced for several samples of the putative hybrid and its putative parental species. Overall, the entire population of H. bermejoi greatly increased from 2010 (last census with available data) to 2015 in terms of both number of patches and area of occupancy: from 110 to 277 patches and from 299.2 to 791.3 dm 2 . Molecular analysis confirmed the hybrid origin of Helosciadium × clandestinum Rita, Capó and Cursach and that both H. bermejoi and H. nodiflorum (L.) Koch can act as donors of pollen or ovules. We discuss the advantages and disadvantages of translocations, as well as the great importance of monitoring them for at least the next ten years, both to know if the actions have been successful and to prevent or mitigate risks. We also present this case as an example for the importance of fast decision and coordination between environmental managers. [ABSTRACT FROM AUTHOR]

Natural areas are often managed for the protection of native species and ecosystems. The presence of non-native species is generally perceived to run counter to these objectives; thus, they are often controlled or tolerated but rarely deliberately favored. We suggest greater emphasis be placed on the role species play in ecological settings regardless of their origin, recognizing that only some non-native plants are invasive, that the risk of causing ecological harm varies considerably, and that distributions will change as species migrate in response to climate change. We sense a disparity between the way this topic-conservation value of non-native species-is addressed in the literature and how it is applied in management of natural areas. To encourage more discussion and consideration of appropriate roles for non-natives in natural areas management, we present five case studies illustrating their value in the conservation of rare and endangered species, including Taylor's checkerspot and island marble butterflies, southwestern willow flycatcher, and the giant kangaroo rat. Our last case study describes a proposed conservation action for the rare Brewer spruce-that of assisted colonization, itself the creation of a non-native for conservation purposes. Although we support continued avoidance of introducing invasives and a cautious treatment of non-natives, we encourage those with responsibility for natural areas management to not only evaluate the threats posed by non-natives, but to also consider their potential benefits in relation to management objectives. [ABSTRACT FROM AUTHOR]

Hawaiian forest birds are imperiled, with fewer than half the original >40 species remaining extant. Recent studies document ongoing rapid population decline and project complete climate-based range losses for the critically endangered Kaua'i endemics 'akeke'e ( Loxops caeruleirostris) and 'akikiki ( Oreomystis bairdi) by end-of-century due to projected warming. Climate change facilitates the upward expansion of avian malaria into native high elevation forests where disease was historically absent. While intensified conservation efforts attempt to safeguard these species and their habitats, the magnitude of potential loss and the urgency of this situation require all conservation options to be seriously considered. One option for Kaua'i endemics is translocation to islands with higher elevation habitats. We explored the feasibility of interisland translocation by projecting baseline and future climate-based ranges of 'akeke'e and 'akikiki across the Hawaiian archipelago. For islands where compatible climates for these species were projected to endure through end-of-century, an additional climatic niche overlap analysis compares the spatial overlap between Kaua'i endemics and current native species on prospective destination islands. Suitable climate-based ranges exist on Maui and Hawai'i for these Kaua'i endemics that offer climatically distinct areas compared to niche distributions of destination island endemics. While we recognize that any decision to translocate birds will include assessing numerous additional social, political, and biological factors, our focus on locations of enduring and ecologically compatible climate-based ranges represents the first step to evaluate this potential conservation option. Our approach considering baseline and future distributions of species with climatic niche overlap metrics to identify undesirable range overlap provides a method that can be utilized for other climate-vulnerable species with disjointed compatible environments beyond their native range. [ABSTRACT FROM AUTHOR]

The Manchurian trout, Brachymystax lenok tsinlingensis (family: Salmonidae), is a cold freshwater fish endemic to Northeast Asia. South Korean populations of this species, which comprise its southern range limit, have recently decreased markedly in size and are now becoming critically endangered. We assessed the current population status of this species in South Korea by estimating the levels of genetic diversity and genetic structure of five natural and four restored populations using mitochondrial DNA (mtDNA) control region sequences and eight nuclear microsatellite loci. Levels of within-population genetic diversity were low, suggesting that past effective population sizes ( N ) have been small. Each population had one or a maximum of two mtDNA haplotypes. Microsatellite allelic richness (AR) was significantly higher for natural populations (mean AR = 3.51; 95% confidence interval, 3.00-4.03) than for restored populations (mean AR = 2.61; 2.38-2.98). South Korean populations were significantly genetically isolated from one another, with private mtDNA haplotypes and microsatellite alleles, suggesting that limited gene flow has been occurring among populations. A mtDNA phylogeny revealed that South Korean lineages were more closely related to those of China than to those of North Korea and Russia. Overall, we suggest that future restoration efforts aimed at South Korean populations should consider the genetic characteristics reported here, which should help to fulfil effective conservation strategies for this highly cherished species. Our results will inform other conservation efforts, including assisted migration of freshwater fish populations at the equatorial end of the geographical range limit of the species. [ABSTRACT FROM AUTHOR]

Threatened species with reduced and fragmented habitats can be reintroduced into their historical ranges to establish new populations. Multiple sites might be an option for reintroductions; therefore, managers must determine when to open sites (e.g. establish infrastructure and improve conditions), release individuals into those sites, and eventually cease releases. Careful planning of this schedule, incorporating the cost of actions, is imperative at the outset of a program. To address this challenge, we consider a reintroduction plan under different cost scenarios for three potential reintroduction sites. In particular, we investigate the implications of having either no ongoing site-management cost, a financial ongoing site-management cost, or a demographic cost of continuous releases. We couple population and management models to find a schedule that maximizes total abundance over time of bridled nail-tail wallaby Onychogalea fraenata (released in fixed numbers each breeding season from a stable source population) using stochastic dynamic programming. We find that the type of ongoing cost influences the structure of the optimal schedule. If active release sites cost nothing to maintain, there is no incentive to cease releases. In that case, the optimal schedule is to open sites sequentially, then release individuals to the smallest active population for the entire length of the program. A financial cost for managing active sites alters this result; once all sites are open and have populations of a critical threshold size, sites should be closed sequentially. A higher mortality rate (demographic cost) at active compared to inactive sites completely changes the structure of the optimal strategy. Instead of opening all sites in the first few management stages, only one site should be active any time to reduce the demographic impact of releases. Our general results provide a guide for planning future reintroduction programs and illustrate the importance of categorizing and understanding ongoing costs for reintroduction planning. [ABSTRACT FROM AUTHOR]

Conservation introduction (CI), i.e. moving a species out of its current natural range for conservation purposes, is a highly controversial and rarely attempted conservation measure. One particular concern with these conservation actions is whether species with obligate symbiotic relationships will be able to form these associations in the recipient locations. This study takes advantage of a massive conservation translocation of orchids at the Yachang National Nature Reserve in southwestern China. We compared the mycorrhizal associations of four of these targeted species. Two of the species ( Cymbidium bicolor Lindl. and Geodorum eulophioides Schltr.) had narrow geographic ranges and were subjected to CI because the movement had placed them out of their natural ranges. While the other two species ( Paphiopedilum dianthum , Tang and Wang, and Paphiopedilum hirsutissimum , (Lindl. ex Hook. f.) Pfitzer) had wide geographic ranges and were not moved outside of them. This movement can be considered a conventional translocation. Using DNA techniques, we identified orchid mycorrhizal fungi (OMF) associated with translocated and natural populations of these species. Our results indicated that translocated populations of both kinds (CI and conventional translocation) were able to establish new relationships with root fungi, including known OMF groups. Wide-ranging species associated with a greater number (24 OTUs) and more diverse groups of fungi (Shannon diversity ( H ′) = 0.93) than narrow range species (15 OTUs, H ′ = 0.62). However, translocated populations of wide-ranging species shared fewer fungi with their natural populations than those of narrow-ranging species. This research provides the first evaluation of how critical biotic interactions may change following conservation introduction compared to that of conventional translocation, and shed light upon the feasibility of conservation introduction. [ABSTRACT FROM AUTHOR]

The high rate of anthropogenic climate change projected for coming decades and evidence of low migration ability for many species have led researchers to warn of a looming extinction crisis. This threat is expected to be most acute for small-ranged endemic species, which could see novel climatic conditions develop rapidly across the entirety of their limited geographic ranges. To avoid extinctions, some conservationists have proposed that climate-imperiled species might be candidates for 'assisted colonization' or 'managed relocation' to new regions, outside their historical ranges. One major concern related to managed relocation is the possibility that some relocated species could later become problematic invasives where they are introduced. In this review, we consider how these emerging conservation challenges might unfold for the flora of New England. A range of evidence suggests that most plant species native to New England might be resilient to immediate extinction risk from climate change, as these species typically have broad geographic ranges and have migrated long distances in response to past climate change. In contrast, regions to the south, particularly hotspots of plant endemism in the southeastern US, harbor numerous small-ranged species whose current climatic niches could rapidly shift beyond their native ranges, leaving them vulnerable to extinction unless they colonize new regions to the north. Consequently, debates surrounding managed relocation in New England are likely to be focused primarily on the ecological risks versus conservation benefits of accepting climate-threatened endemic plant species from the southeastern US, and to hinge on concerns about the invasive potential of these species. To provide an empirically-grounded estimate of invasion risk from the introduction of US native plant species to New England, we reviewed invasive species lists for New England and tallied those species that are native to other parts of the contiguous US (versus other regions and continents). Between four and ten 'invasive' or 'potentially invasive' plant species reported from New England are from other regions of the contiguous US, depending in part on how issues of native versus exotic genotypes within taxa are resolved. A review of current floristic data from New England shows that these 4-10 problematic species are drawn from a larger pool of ∼374 US native plant species reported as exotic in the region, suggesting that only 1.1-2.7% of species appearing spontaneously as adventives in the region are viewed as invasive. In light of this analysis, we suggest that managed relocation is not likely to spawn large numbers of new invasives, and might therefore be judiciously evaluated alongside other conservation options for climate-threatened plant species. We propose a collaborative effort among field botanists, land managers, conservationists, and academics in New England, partnering with botanists in the southeastern US, to initiate fundamental research to experimentally test the viability and ecological effects of climate-threatened endemic plant species from the southeastern US in the New England region. [ABSTRACT FROM AUTHOR]

Assisted migration is recognized as a possible method for species conservation under climate change. Predicted decrease in range size and emergence of new suitable areas due to climate change are the main reasons for considering assisted migration. The magnitude of such changes can be used to guide decisions on the applicability of this conservation method. However, it has not been formalized how predictions acquired, e.g., with the help of species distribution models or expert assessments, should translate into recommendations or decisions. Climate change threat indices concentrating on predicted loss of habitat are not directly applicable in this context as they do not define whether a species has the potential to expand its range compared to the area that remains suitable. Here we present a conceptual framework for identifying and quantifying situations in which predictions indicate that a species could benefit from assisted migration. We translate predicted changes in suitable area into separate metrics for migration need and migration potential on the basis of the amount of lost, remnant, and new area. These metrics can be used as part of decision-making frameworks in determining the most suitable conservation method for a specific species. They also hold potential for coarser screening of multiple species to estimate the proportion of species that could benefit from assisted migration within a given time frame and climate change scenario. Furthermore, the approach can be used to highlight time frames during which assisted migration or, alternatively, other conservation actions are the most beneficial for a certain species. [ABSTRACT FROM AUTHOR]

Assisted migration entails the human assisted movement of individuals to more climatically-suitable areas within or outside of their current species range to help species respond to climate change. To better understand the potential for assisted migration to benefit species threatened by climate change, we conducted an evidence synthesis to map examples where assisted migration has been implemented around the world. With this mapping exercise, we collate and describe the quantity and key characteristics of the available evidence base, including the taxa, species conservation status, locations, and contexts relating to the use of this conservation tactic. Findings from this exercise highlight that assisted migration has been implemented very few times as a conservation tactic, though assisted migration has been conducted experimentally (for research purposes) and inadvertently (e.g., for reforestation) much more frequently. Assisted migration was most common for plants (particularly trees), followed by birds, and was rarely implemented for other taxa. Our review highlights the need for more research on assisted migration, with particular emphasis on understanding the population- and community-level outcomes of these actions. Our discussion focuses on the potential for assisted migration of Canadian species but will be informative to those considering assisted migration in other jurisdictions. • We conducted an evidence synthesis to map examples where assisted migration has been implemented around the world. • Cases of assisted migration for conservation have been rare compared to experimental and inadvertent cases. • Assisted migration of plants (particularly trees) was most common while for other taxa was uncommon. • More research on assisted migration is needed, particularly on population- and community-level outcomes. [ABSTRACT FROM AUTHOR]

The use of conservation translocations to mitigate human effects on biodiversity is increasing, but how these efforts are allocated remains unclear. Based on a comprehensive literature review and online author survey, we sought to determine the goals of translocation efforts, whether they focus on species and regions with high threat and likelihood of perceived success, and how success might be improved. We systematically searched the ISI Web of Knowledge and Academic Search Complete databases to determine the species and regions of conservation translocations and found 1863 articles on conservation translocations in the United States, Canada, Mexico, Central America, and Caribbean published from 1974 to 2013. We questioned 330 relevant authors to determine the motivation for translocations, how translocations were evaluated, and obstacles encountered. Conservation translocations in North America were geographically widespread (in 21 countries), increased in frequency over time for all animal classes (from 1 in 1974 to 84 in 2013), and included 279 different species. Reintroductions and reinforcements were more common in the United States than in Canada and Mexico, Central America, or the Caribbean, and their prevalence was correlated with the number of species at risk at national and state or provincial levels. Translocated species had a higher threat status at state and provincial levels than globally (International Union for Conservation of Nature Red List categorization), suggesting that translocations may have been motivated by regional priorities rather than global risk. Our survey of authors was consistent with these results; most translocations were requested, supported, or funded by government agencies and downlisting species at national or state or provincial levels was the main goal. Nonetheless, downlisting was the least reported measure of success, whereas survival and reproduction of translocated individuals were the most reported. Reported barriers to success included biological factors such as animal mortality and nonbiological factors, such as financial constraints, which were less often considered in the selection of release sites. Our review thus highlights discrepancies between project goals and evaluation criteria and between risk factors considered and obstacles encountered, indicating room to further optimize translocation projects. [ABSTRACT FROM AUTHOR]

The embryos of many egg-laying species develop under the environmental conditions selected by one or both parents, and these conditions may cease to be optimal under a changed climate. Assisted colonization is an emerging option to relocate species that are threatened by unfavourable changes in the local climate, but the incubation requirements of embryos are rarely considered in conservation translocations despite suggestions that relocation of early life stages could be more effective than relocating older animals. Here we review examples and outcomes of relocations of reptile eggs, and the decision tools currently available for guiding translocation decisions from an embryonic perspective. We then demonstrate a mechanistic approach, using the modelling framework NicheMapR, for assessing the optimal translocation range for the Western Swamp Turtle ( Pseudemydura umbrina ), a Critically Endangered reptile with an extremely restricted natural distribution. We determine thermal reaction norms and critical thermal limits for embryonic development based on laboratory and field data, and model soil temperatures at typical nest depths, simulate embryonic development at these depths, and map the probability of survival of P. umbrina embryos within the major bioregions of south-western Australia. The same model forced by future climates for 2050–70 demonstrates a southerly shift in the regions where embryos would be viable. However, if P. umbrina is to be translocated in the near future to regions 300–400 km south of its natural range, females will need to nest in relatively unshaded sites to achieve temperatures that are high enough to promote hatchling success. [ABSTRACT FROM AUTHOR]

Assisted colonization—the deliberate translocation of species from unsuitable to suitable regions—is a controversial management tool that aims to prevent the extinction of populations that are unable to migrate in response to climate change or to survive in situ. The identification of suitable translocation sites is therefore a pressing issue. Correlative species distribution models, which are based on occurrence data, are of limited use for site selection for species with historically restricted distributions. In contrast, mechanistic species distribution models hold considerable promise in selecting translocation sites. Here we integrate ecoenergetic and hydrological models to assess the longer-term suitability of the current habitat of one of the world’s rarest chelonians, the Critically Endangered Western Swamp Tortoise (Psuedemydura umbrina). Our coupled model allows us to understand the interaction between thermal and hydric constraints on the foraging window of tortoises, based on hydrological projections of its current habitat. The process can then be repeated across a range of future climates to identify regions that would fall within the tortoise’s thermodynamic niche. The predictions indicate that climate change will result in reduced hydroperiods for the tortoises. However, under some climate change scenarios, habitat suitability may remain stable or even improve due to increases in the heat budget. We discuss how our predictions can be integrated with energy budget models that can capture the consequences of these biophysical constraints on growth, reproduction and body condition.

An increased understanding of the current and potential future impacts of climate change has significantly influenced conservation in practice in recent years. Climate change has necessitated a shift toward longer planning time horizons, moving baselines, and evolving conservation goals and targets. This shift has resulted in new perspectives on, and changes in, the basic approaches practitioners use to conserve biodiversity. Restoration, spatial planning and reserve selection, connectivity modelling, extinction risk assessment, and species translocations have all been reimagined in the face of climate change. Restoration is being conducted with a new acceptance of uncertainty and an understanding that goals will need to shift through time. New conservation targets, such as geophysical settings and climatic refugia, are being incorporated into conservation plans. Risk assessments have begun to consider the potentially synergistic impacts of climate change and other threats. Assisted colonization has gained acceptance in recent years as a viable and necessary conservation tool. This evolution has paralleled a larger trend in conservation—a shift toward conservation actions that benefit both people and nature. As we look forward, it is clear that more change is on the horizon. To protect biodiversity and essential ecosystem services, conservation will need to anticipate the human response to climate change and to focus not only on resistance and resilience but on transitions to new states and new ecosystems.