Center for Plant Conservation's Best Practice Guidelines for the reintroduction of rare plants

Best practices, errors, and perspectives of half a century of plant translocation in Italy

Conservation translocations are becoming common conservation practice, so there is an increasing need to understand the drivers of plant translocation performance through reviews of cases at global and regional levels. The establishment of the Italian Database of Plant Translocation (IDPlanT) provides the opportunity to review the techniques used in 186 plant translocation cases performed in the last 50 years in the heart of the Mediterranean Biodiversity Hotspot. We described techniques and information available in IDPlanT and used these data to identify drivers of translocation outcomes. We tested the effect of 15 variables on survival of translocated propagules as of the last monitoring date with binomial logistic mixed-effect models. Eleven variables significantly affected survival of transplants: life form, site protection, material source, number of source populations, propagation methods, propagule life stage, planting methods, habitat suitability assessment, site preparation, aftercare, and costs. The integration of vegetation studies in the selection of suitable planting sites significantly increased the success of translocation efforts. Although posttranslocation watering had a generally positive effect on translocation outcome, other aftercare techniques did not always increase transplant survival. Finally, we found that how funds were spent appeared to be more important than the actual amount spent. Plant translocations in Italy and in the Mediterranean area should account for the complexity of speciation, gene flow, and plant migrations that has led to local adaptations and has important implications for the choice and constitution of source material.

Advancing the science and practice of rare plant conservation with the Center for Plant Conservation Reintroduction Database

Premise

Reintroductions or translocations are an increasingly important activity to recover and conserve at-risk plant species. Yet because many are not published in the scientific literature, learning from previous attempts may often require considerable time and effort. The Center for Plant Conservation Reintroduction Database (CPCRD; https://saveplants.org/reintroduction-database/), a new centralized and standardized repository of U.S.-based plant reintroductions, aims to improve the efficiency and effectiveness of accessing data on rare plant reintroductions.

Methods

The CPCRD is the product of multiple efforts to assemble information on rare plant reintroductions in the United States. The database comprises a wealth of standardized data on the key stages of a reintroduction, from the planning and implementation phases, to monitoring and management techniques.

Results

The CPCRD is a dynamic resource, allowing data contributors to continually update their entries as projects progress. While contributions are ongoing, the CPCRD currently includes 460 projects involving 201 plant taxa, spanning diverse growth forms, ecosystems, and regions.

Discussion

The CPCRD and its well-documented and monitored projects provide a valuable practical resource for conservation practitioners, and have supported multiple scientific studies and contributed to the internationally recognized Center for Plant Conservation Best Practices Guidelines.

Identifying predictors of translocation success in rare plant species

The fundamental goal of a rare plant translocation is to create self-sustaining populations with the evolutionary resilience to persist in the long term. Yet, most plant translocation syntheses focus on a few factors influencing short-term benchmarks of success (e.g., survival and reproduction). Short-term benchmarks can be misleading when trying to infer future growth and viability because the factors that promote establishment may differ from those required for long-term persistence. We assembled a large (n = 275) and broadly representative data set of well-documented and monitored (7.9 years on average) at-risk plant translocations to identify the most important site attributes, management techniques, and species' traits for six life-cycle benchmarks and population metrics of translocation success. We used the random forest algorithm to quantify the relative importance of 29 predictor variables for each metric of success. Drivers of translocation outcomes varied across time frames and success metrics. Management techniques had the greatest relative influence on the attainment of life-cycle benchmarks and short-term population trends, whereas site attributes and species' traits were more important for population persistence and long-term trends. Specifically, large founder sizes increased the potential for reproduction and recruitment into the next generation, whereas declining habitat quality and the outplanting of species with low seed production led to increased extinction risks and a reduction in potential reproductive output in the long-term, respectively. We also detected novel interactions between some of the most important drivers, such as an increased probability of next-generation recruitment in species with greater seed production rates, but only when coupled with large founder sizes. Because most significant barriers to plant translocation success can be overcome by improving techniques or resolving site-level issues through early intervention and management, we suggest that by combining long-term monitoring with adaptive management, translocation programs can enhance the prospects of achieving long-term success.

Demography and threats to population growth of Cirsium pitcheri, a threatened dune plant, in Wisconsin

Multi-year and multi-site demographic data for rare plants allow researchers to observe threats and project population growth rates and thus long-term persistence of the species, generating knowledge, which allows for effective conservation planning. Demographic studies across more than a decade are extremely rare but allow for the effects of threats to be observed and assessed within the context of interannual environmental variation. We collected demographic data on the Threatened plant Cirsium pitcheri in two sites from 2011-2022. These sites were chosen because one exhibited the presence of non-native seed predators while the other did not, and we hypothesized that we would see declines and potentially extinction of the population threatened by predation. Over the course of our study, we observed additional threats, such as human trampling and high lake levels, which led to significant erosion, sand burial, and storm damage to plants. We find high interannual variation in vital rates and population growth rates for both populations, which mask the overall effects of predation. We observed dramatic declines in plant survivorship and population growth rates in both sites in the years with high lake levels. We conclude that high lake levels, which are expected to become more frequent with climate change, pose a significant threat to all near-shore populations of C. pitcheri.

Selecting the best candidates for resurrecting extinct-in-the-wild plants from herbaria

Resurrecting extinct species is a fascinating and challenging idea for scientists and the general public. Whereas some theoretical progress has been made for animals, the resurrection of extinct plants (de-extinction sensu lato) is a relatively recently discussed topic. In this context, the term 'de-extinction' is used sensu lato to refer to the resurrection of 'extinct in the wild' species from seeds or tissues preserved in herbaria, as we acknowledge the current impossibility of knowing a priori whether a herbarium seed is alive and can germinate. In plants, this could be achieved by germinating or in vitro tissue-culturing old diaspores such as seeds or spores available in herbarium specimens. This paper reports the first list of plant de-extinction candidates based on the actual availability of seeds in herbarium specimens of globally extinct plants. We reviewed globally extinct seed plants using online resources and additional literature on national red lists, resulting in a list of 361 extinct taxa. We then proposed a method of prioritizing candidates for seed-plant de-extinction from diaspores found in herbarium specimens and complemented this with a phylogenetic approach to identify species that may maximize evolutionarily distinct features. Finally, combining data on seed storage behaviour and longevity, as well as specimen age in the novel 'best de-extinction candidate' score (DEXSCO), we identified 556 herbarium specimens belonging to 161 extinct species with available seeds. We expect that this list of de-extinction candidates and the novel approach to rank them will boost research efforts towards the first-ever plant de-extinction.

The Importance of Groundwater Quality and Other Habitat Parameters for Effective Active Protection of an Endangered Plant Species in Eastern Poland

Anthropogenic habitat transformations involving changes in hydrologic conditions in the peatlands of eastern Poland contribute to the disappearance of sites of numerous relict plant species. The study aimed to verify whether sites chosen for the reintroduction of the endangered species Salix lapponum had been well selected by analyzing selected habitat parameters and determining whether changes in their values may in the long term have a significant impact on the functioning of new populations of the species. The results obtained at sites where the S. lapponum population was replenished with new individuals were analyzed in relation to data from one of the natural sites of the species. Hydrochemical characterization of the groundwater at the study sites confirmed that there was no significant influx of nutrients into the habitat or other hydrological disturbances due to human activity. The values obtained for the factors tested were within the limits of the specific preferences of the species. Changes in the values of some physical-chemical parameters of the water were due to the ecosystem’s internal metabolism, and the site with the highest hydrochemical stability was the one where S. lapponum occurred naturally. The species composition and structure of the phytocoenoses at all study sites were characteristic of natural sites of the species and showed no disturbances caused by human impact. The microbiological analyses indicated normal soil processes. The hydrochemical and biocoenotic stability of the habitat, including the microbiological balance of the soil, which was free of pathogenic fungi, should have a positive effect on the condition of the reintroduced plants.

Little hope for the polyploid endemic Pyrenean Larkspur (Delphinium montanum): Evidences from population genomics and Ecological Niche Modeling

Species endemic to restricted geographical ranges represent a particular conservation issue, be it for their heritage interest. In a context of global change, this is particularly the case for plants which belong to high-mountain ecosystems and, because of their ecological requirements, are doomed to survive or disappear on their "sky islands". The Pyrenean Larkspur (Delphinium montanum, Ranunculaceae) is endemic to the Eastern part of the Pyrenees (France and Spain). It is now only observable at a dozen of localities and some populations show signs of decline, such as a recurrent lack of flowering. Implementing population genomics approach (e.g., RAD-seq like) is particularly useful to understand genomic patterns of diversity and differentiation in order to provide recommendations in term of conservation. However, it remains challenging for species such as D. montanum that are autotetraploid with a large genome size (1C-value >10 pg) as most methods currently available were developed for diploid species. A Bayesian framework able to call genotypes with uncertainty allowed us to assess genetic diversity and population structure in this system. Our results show evidence for inbreeding (mean G IS = 0.361) within all the populations and substantial population structure (mean G ST = 0.403) at the metapopulation level. In addition to a lack of connectivity between populations, spatial projections of Ecological Niche Modeling (ENM) analyses under different climatic scenarios predict a dramatic decrease of suitable habitat for D. montanum in the future. Based on these results, we discuss the relevance and feasibility of different conservation measures.

Assessing Population Genetic Status for Designing Plant Translocations

Assisted gene flow interventions such as plant translocations are valuable complementary techniques to habitat restoration. Bringing new genetic variants can contribute to increasing genetic diversity and evolutionary resilience, counteract inbreeding depression and improve plant fitness through heterosis. Large, highly genetically variable populations are usually recommended as sources for translocation. Unfortunately, many critically endangered species only occur as small populations, which are expected to show low genetic variation, high inbreeding level, paucity of compatible mates in self-incompatible species, and increased genetic divergence. Therefore, assessment of population genetic status is required for an appropriate choice of the source populations. In this paper, we exemplify the different analyses relevant for genetic evaluation of populations combining both molecular (plastid and nuclear) markers and fitness-related quantitative traits. We assessed the genetic status of the adult generation and their seed progeny (the potential translocation founders) of small populations of Campanula glomerata (Campanulaceae), a self-incompatible insect-pollinated herbaceous species critically endangered in Belgium. Only a few small populations remain, so that the species has been part of a restoration project of calcareous grasslands implementing plant translocations. In particular, we estimated genetic diversity, inbreeding levels, genetic structure in adults and their seed progeny, recent bottlenecks, clonal extent in adults, contemporary gene flow, effective population size (Ne), and parentage, sibship and seed progeny fitness variation. Small populations of C. glomerata presented high genetic diversity, and extensive contemporary pollen flow within populations, with multiple parentage among seed progenies, and so could be good seed source candidates for translocations. As populations are differentiated from each other, mixing the sources will not only optimize the number of variants and of compatible mates in translocated populations, but also representativeness of species regional genetic diversity. Genetic diversity is no immediate threat to population persistence, but small Ne, restricted among-population gene flow, and evidence of processes leading to genetic erosion, inbreeding and inbreeding depression in the seed progeny require management measures to counteract these trends and stochastic vulnerability. Habitat restoration facilitating recruitment, flowering and pollination, reconnecting populations by biological corridors or stepping stones, and creating new populations through translocations in protected areas are particularly recommended.

Guidelines for genetic monitoring of translocated plant populations

Plant translocation is a useful tool for implementing assisted gene flow in recovery plans of critically endangered plant species. Although it helps to restore genetically viable populations, it is not devoid of genetic risks, such as poor adaptation of transplants and outbreeding depression in the hybrid progeny, which may have negative consequences in terms of demographic growth and plant fitness. Hence, a follow-up genetic monitoring should evaluate whether the translocated populations are genetically viable and self-sustaining in the short and long term. The causes of failure to adjust management responses also need to be identified. Molecular markers and fitness-related quantitative traits can be used to determine whether a plant translocation enhanced genetic diversity, increased fitness, and improved the probability of long-term survival. We devised guidelines and illustrated them with studies from the literature to help practitioners determine the appropriate genetic survey methods so that management practices can better integrate evolutionary processes. These guidelines include methods for sampling and for assessing changes in genetic diversity and differentiation, contemporary gene flow, mode of local recruitment, admixture level, the effects of genetic rescue, inbreeding or outbreeding depression and local adaptation on plant fitness, and long-term genetic changes.

Quality assessment of mitigation translocation protocols for protected plants in France

Mitigation translocations are increasingly used worldwide in response to land planning pressures. The quality of translocation protocols and their adjustment to the ecological traits of the translocated populations are crucial to optimise translocation success. We studied the quality of translocation protocols presented in derogation requests, a mandatory step in France to translocate a protected plant species. We analysed 103 translocation proposals for 93 different species in 92 files examined between 2018 and 2020. After tracing the history of the place of translocations in legal procedures in France, we assessed each translocation proposal according to an evaluation grid, which involved the quantity and quality of information on plant species and translocation sites in the files and the quality of translocation protocols. We have shown that the translocation protocols are of low quality, with a lot of missing information. The biology and ecology of the species suggested for translocation are not sufficiently known, nor are the ecological characteristics of the host sites. Derogation requests that received a favourable opinion from the assessment body are more likely to propose a protected host site and post-translocation monitoring. We believe that, to optimise their outcome, mitigation translocations need to be improved upstream, with more detailed protocols and better species knowledge. We highly recommend following the same guidelines for mitigation translocations as for conservation translocations.

Threatened Plant Translocation for Mitigation: Improving Data Accessibility Using Existing Legislative Frameworks. An Australian Case Study

Translocation of plants is used globally as a conservation action to bolster existing or establish new populations of threatened species and is usually communicated in academic publications or case studies. Translocation is also used to mitigate or offset impacts of urbanization and development but is less often publicly published. Irrespective of the motivation, conservation or mitigation, on ground actions are driven by overriding global conservation goals, applied in local or national legislation. This paper deconstructs the legislative framework which guides the translocation process in Australia and provides a case study which may translate to other countries, grappling with similar complexities of how existing legislation can be used to improve accessibility of translocation records. Each year, across Australia, threatened plants are being translocated to mitigate development impacts, however, limited publicly accessible records of their performance are available. To improve transparency and opportunities to learn from the outcomes of previous mitigation translocations, we propose mandatory recording of threatened plant translocations in publicly accessible databases, implemented as part of development approval conditions of consent. The contribution to these need not be onerous, at a minimum including basic translocation information (who, what, when) at project commencement and providing monitoring data (outcome) at project completion. These records are currently already collected and prepared for translocation proposals and development compliance reporting. Possible repositories for this information include the existing national Australian Network for Plant Conservation translocation database and existing State and Territory databases (which already require contributions as a condition of licensing requirements) with new provisions to identify and search for translocation records. These databases could then be linked to the Atlas of Living Australia and the Australian Threatened Plant Index. Once established, proposals for mitigation translocation could be evaluated using these databases to determine the viability of mitigation translocation as an offset measure and to build on the work of others to ensure better outcomes for plant conservation, where translocations occur.

Strategies for reintroduction and conservation of Gymnopogon doellii, an endemic grass at risk of extinction

Abstract The Brazilian savanna, regionally known as Cerrado, is characterized by a great diversity of physiognomies and holds the highest species diversity and level of endemism among world savannas. However, due mainly to agribusiness, this vegetation is among the most threatened ones, currently presenting alarming rates of extinction. Among the species present in the “red list” we find the endemic Gymnopogon doellii, a grass whose distribution is restricted to a few sites. In the Federal District and surroundings, for example, only one population, with scattered subpopulations, is known, within the limits of the Brasilia National Park. By this study we raised information related to the biology of G. doellii, as population size and distribution, genetic variability and germination characteristics. Besides, we produced seedlings in greenhouse, planted in different physiognomies of the Cerrado and followed them for almost four years to check for their survival, growth and fruiting under natural conditions. Seedlings transplanted to the field presented high rates of recruitment (> 25%), growth patterns similar to wild plants and produced viable caryopses. We recommend transplanting of individuals of G. doellii for both in situ conservation as well as for the revegetation of degraded areas of the Cerrado.

Public Attitudes towards Birds and Private Forest Land Conservation

The eastern United States is dominantd by private forest lands, which are important for supporting a significant proportion of global bird populations. Here, we examine public attitudes towards bird conservation, government involvement in private lands issues, and private forest management objectives with an aim to better understand how these perceptions may shape broader attitudes about bird conservation. Data were collected using psychometric scales and a statewide web survey of the general public in Pennsylvania, USA (n = 656). Findings reveal four unique perspectives about birds and important correlations with conservation support on private lands. Respondents with positive views about landowner assistance programs often had more complex attitudes towards birds and were associated with relational and ethical perspectives about birds. We conclude that future public education efforts might cultivate in learners a more robust understanding of bird conservation if they included private forest lands values and culture in their programs.

Dalziell E, Trudgen MS, Bateman AM, Erickson TE. Global change impacts on arid zone ecosystems: Seedling establishment processes are threatened by temperature and water stress

Recruitment for many arid-zone plant species is expected to be impacted by the projected increase in soil temperature and prolonged droughts associated with global climate change. As seed dormancy is considered a strategy to avoid unfavorable conditions, understanding the mechanisms underpinning vulnerability to these factors is critical for plant recruitment in intact communities, as well as for restoration efforts in arid ecosystems. This study determined the effects of temperature and water stress on recruitment processes in six grass species in the genus Triodia R.Br. from the Australian arid zone. Experiments in controlled environments were conducted on dormant and less-dormant seeds at constant temperatures of 25°C, 30°C, 35°C, and 40°C, under well-watered (Ψsoil = -0.15 MPa) and water-limited (Ψsoil = -0.35 MPa) conditions. Success at three key recruitment stages-seed germination, emergence, and survival-and final seed viability of ungerminated seeds was assessed. For all species, less-dormant seeds germinated to higher proportions under all conditions; however, subsequent seedling emergence and survival were higher in the more dormant seed treatment. An increase in temperature (35-40°C) under water-limited conditions caused 95%-100% recruitment failure, regardless of the dormancy state. Ungerminated seeds maintained viability in dry soil; however, when exposed to warm (30-40°C) and well-watered conditions, loss of viability was greater from the less-dormant seeds across all species. This work demonstrates that the transition from seed to established seedling is highly vulnerable to microclimatic constraints and represents a critical filter for plant recruitment in the arid zone. As we demonstrate temperature and water stress-driven mortality between seeds and established seedlings, understanding how these factors influence recruitment in other arid-zone species should be a high priority consideration for management actions to mitigate the impacts of global change on ecosystem resilience. The knowledge gained from these outcomes must be actively incorporated into restoration initiatives.

Conservation of a Critically Endangered Endemic Halophyte of West Portugal: A Microcosm Assay to Assess the Potential of Soil Technology for Species Reintroduction

The soil system has been frequently overlooked during plant reintroduction planning and practice since working with soils and plant roots can be difficult, particularly in saline environments. Coastal saline environments are major contributors to regional and global biodiversity and an important source of endemic species. However, various species are in decline or considered threatened, particularly halophytes (salt tolerant) due to negative anthropic impacts. The Lusitanian endemic halophyte Limonium daveaui formerly had a large distribution range along the west coast of Portugal but currently it shows a restricted distribution in the Tagus estuary. Field surveys revealed that this critically endangered species forms few local populations with small size invaded by exotic species. In this study, we investigated the potential utilization of Technosols, an innovative sustainable, ecological engineering method combined with brackish water irrigation for potential L. daveaui reintroduction in native habitats. Seed germination percentages were evaluated in different environmental conditions. Through a microcosm assay, a Technosol was constructed using a saline Fluvisol with a mixture of low value inorganic and organic wastes, which were chemically characterized. Plants were cultivated in the Fluvisol and Technosol and irrigated with brackish water collected in the nearby area. To assess plant growth, morphometric parameters and the plants’ physiological status were assessed and the fresh and dry biomass determined. Results showed that seed germination was higher on moist filter paper with distilled water than in Fluvisol or Technosol. Plants grown in Technosol had a greater development, with higher values of photosynthetic indexes and biomass production than in Fluvisol. Our findings provide a basis for future in situ conservation studies and support the idea that eco-friendly soil technology approaches are beneficial to conserve rare halophyte species.

Mixing gene pools to prevent inbreeding issues in translocated populations of clonal species

Assisted gene flow by plant translocations is increasingly implemented for restoring populations of critically endangered species. The success in restoring genetically healthy populations may depend on translocation design, in particular the choice of the source populations. Highly clonal populations may show low genetic diversity despite large census sizes, and disrupted and geitonogamous pollination may result in selfing and inbreeding issues in the offspring intended for translocation. We carried out a genetic monitoring of translocated populations of the clonal Dianthus deltoides using 14 microsatellite markers and quantified fitness traits over two generations (transplants, F1 seed progeny and newly established individuals). Inbreeding levels were higher in the offspring used as transplants than in the adult generation of the source populations, as a result of high clonality and pollination disruption leading to self-pollination. The F1 generation in translocated populations showed high genetic diversity maintained across generations, diminished inbreeding levels, low genetic differentiation, pollen flow and genetic mixing between the four sources. New individuals were established from seed germination. Fitness patterns were a combination of inbreeding depression in inbred transplants and F1 progeny, heterosis in admixed F1 progeny, source population adaptive capacities, phenotypic plasticity, maternal effects and site environmental specificities. The strategy in the translocation design to mix several local sources, combined with large founding population sizes and ecological management has proved success in initiating the processes leading to the establishment of genetically healthy populations, even when source populations are highly clonal with low genetic diversity leading to inbreeding issues in the transplants.

Using genetic evaluation to guide conservation of remnant Juniperus communis (Cupressaceae) populations

Many critically endangered plant species exist in small, genetically depauperate or inbred populations, making assisted gene flow interventions necessary for long-term population viability. However, before such interventions are implemented, conservation practitioners must consider the genetic and demographic status of extant populations, which are strongly affected by species' life-history traits. In northwestern Europe, Juniperus communis, a dioecious, wind-pollinated and bird-dispersed gymnosperm, has been declining for the past century and largely exists in small, isolated and senescent populations. To provide useful recommendations for a recovery plan involving translocation of plants, we investigated genetic diversity and structure of populations in Belgium using four microsatellite and five plastid single-nucleotide polymorphism (SNP) markers. We detected no clonality in the populations, suggesting predominantly sexual reproduction. Populations exhibited high genetic diversity (H_e  = 0.367-0.563) and low to moderate genetic differentiation (F_ST  ≤ 0.133), with no clear geographic structure. Highly positive inbreeding coefficients (F_IS  = 0.221-0.507) were explained by null alleles, population substructuring and biparental inbreeding. No isolation by distance was observed among distant populations, but isolation at close geographic proximity was found. Patterns were consistent with high historical gene flow through pollen and seed dispersal at both short and long distances. We also tested four pre-germination treatments among populations to improve germination rates; however, germination rates remained low and only cold-stratification treatments induced germination in some populations. To bolster population regeneration, introductions of cuttings from several source populations are recommended, in combination with in situ management practices that improve seedling survival and with ex situ propagation.

One hundred research questions in conservation physiology for generating actionable evidence to inform conservation policy and practice

Environmental change and biodiversity loss are but two of the complex challenges facing conservation practitioners and policy makers. Relevant and robust scientific knowledge is critical for providing decision-makers with the actionable evidence needed to inform conservation decisions. In the Anthropocene, science that leads to meaningful improvements in biodiversity conservation, restoration and management is desperately needed. Conservation Physiology has emerged as a discipline that is well-positioned to identify the mechanisms underpinning population declines, predict responses to environmental change and test different in situ and ex situ conservation interventions for diverse taxa and ecosystems. Here we present a consensus list of 10 priority research themes. Within each theme we identify specific research questions (100 in total), answers to which will address conservation problems and should improve the management of biological resources. The themes frame a set of research questions related to the following: (i) adaptation and phenotypic plasticity; (ii) human-induced environmental change; (iii) human-wildlife interactions; (iv) invasive species; (v) methods, biomarkers and monitoring; (vi) policy, engagement and communication; (vii) pollution; (viii) restoration actions; (ix) threatened species; and (x) urban systems. The themes and questions will hopefully guide and inspire researchers while also helping to demonstrate to practitioners and policy makers the many ways in which physiology can help to support their decisions.

Bi-Pinnate Compound Serianthes nelsonii Leaf-Level Plasticity Magnifies Leaflet-Level Plasticity

Numerous leaf traits exhibit developmental plasticity in response to irradiance, an attribute that maximizes performance in the prevailing light. The use of leaflets to represent whole leaf traits of tree species with compound leaves is common in the acclimation literature. These methods ignore the potential for whole leaf plasticity to augment leaflet plasticity. We grew Serianthes nelsonii plants in incident light ranging from 6% to 100% of sunlight and quantified numerous leaflet and leaf traits to determine plasticity index (PI: (maximum-minimum)/maximum)) of each. Leaflet acclimation such as changes in length of palisade mesophyll occurred as expected. However, leaf-level morphometric traits such as rachillae insertion angle also exhibited acclimation potential. The leaf-level plastic behavior enabled acclimation approaches that simple-leaved species do not possess. We illuminate the need to look at the entire leaf when quantifying acclimation potential of tree leaves, and indicate that the historical use of leaflets to represent species with compound leaves under-estimated the acclimation potential when compared to species with simple leaves.

Genetic monitoring of translocated plant populations in practice

Plant translocations allow the restoration of genetic diversity in inbred and depauperate populations and help to prevent the extinction of critically endangered species. However, the successes of plant translocations in restoring genetically viable populations and the possible associated key factors are still insufficiently evaluated. To fill this gap, we carried out a thorough genetic monitoring of three populations of Arnica montana that were created or reinforced by the translocation of plants obtained from seeds of two large natural source populations from southern Belgium. We genotyped nine microsatellite markers and measured fitness quantitative traits over two generations (transplants, F1 seed progeny and newly established F1 juveniles). Two years after translocation, the genetic restoration had been effective, with high genetic diversity and low genetic differentiation across generations, extensive contemporary pollen flow, admixture between seed sources in the F1 generation and recruitment of new individuals from seeds. We detected site, seed source and maternal plant effects on plant fitness. The results also suggest that phenotypic plasticity may favour short-term individual survival and long-term adaptive capacity and enhance the evolutionary resilience of the populations to changing environmental conditions. We found no sign of heterosis or outbreeding depression at early life stages in the F1 generation. Our findings emphasize the importance of the translocation design (700 transplants of mixed sources, planted at high density) as well as the preparatory site management for the successful outcome of the translocations, which maximized flowering, random mating, and recruitment from seeds in the first years after translocation.

Burrowing activity of coconut rhinoceros beetle on Guam cycads

Guam’s established population of non-native coconut rhinoceros beetle (CRB, Oryctes rhinoceros L.) began creating burrows in stem apices of several cycad species in a managed garden. We conducted an island-wide survey to determine the spatial patterns of CRB burrowing of stems of in situ Cycas micronesica. We also measured starch of healthy and unhealthy coconut leaf tissue and compared this with starch of cycad stem tissue. The starch concentration of the central unexpanded leaf in healthy Philippine coconut trees was ≈90 mg·g⁻¹, and that of unhealthy Guam coconut trees was ≈40 mg·g⁻¹. The starch concentration of the tissue within the CRB burrow locations on C. micronesica trees was 145 mg·g⁻¹. Burrowing of C. micronesica was restricted to female CRB adults and was found throughout the full latitudinal gradient of Guam. Our findings indicate Guam’s unhealthy coconut trees are no longer nutrient-dense, and the female CRB population may have exhibited a phylogenetically distant host shift to the abundant C. micronesica plants for a starch-rich diet within the concepts of the ‘ecological fitting’ hypothesis. We add proximity to coconut tree habitats as a new threat to Guam’s endangered C. micronesica population.

Ex situ collections and their potential for the restoration of extinct plants

The alarming current and predicted species extinction rates have galvanized conservationists in their efforts to avoid future biodiversity losses, but for species extinct in the wild, few options exist. We posed the questions, can these species be restored, and, if so, what role can ex situ plant collections (i.e., botanic gardens, germplasm banks, herbaria) play in the recovery of plant genetic diversity? We reviewed the relevant literature to assess the feasibility of recovering lost plant genetic diversity with using ex situ material and the probability of survival of subsequent translocations. Thirteen attempts to recover species extinct in the wild were found, most of which used material preserved in botanic gardens (12) and seed banks (2). One case of a locally extirpated population was recovered from herbarium material. Eight (60%) of these cases were successful or partially successful translocations of the focal species or population; the other 5 failed or it was too early to determine the outcome. Limiting factors of the use of ex situ source material for the restoration of plant genetic diversity in the wild include the scarcity of source material, low viability and reduced longevity of the material, low genetic variation, lack of evolution (especially for material stored in germplasm banks and herbaria), and socioeconomic factors. However, modern collecting practices present opportunities for plant conservation, such as improved collecting protocols and improved cultivation and storage conditions. Our findings suggest that all types of ex situ collections may contribute effectively to plant species conservation if their use is informed by a thorough understanding of the aforementioned problems. We conclude that the recovery of plant species currently classified as extinct in the wild is not 100% successful, and the possibility of successful reintroduction should not be used to justify insufficient in situ conservation.

Using genomic information for management planning of an endangered perennial, Viola uliginosa

Species occupying habitats subjected to frequent natural and/or anthropogenic changes are a challenge for conservation management. We studied one such species, Viola uliginosa, an endangered perennial wetland species typically inhabiting sporadically flooded meadows alongside rivers/lakes. In order to estimate genomic diversity, population structure, and history, we sampled five sites in Finland, three in Estonia, and one each in Slovenia, Belarus, and Poland using genomic SNP data with double-digest restriction site-associated DNA sequencing (ddRAD-seq). We found monophyletic populations, high levels of inbreeding (mean population F SNP = 0.407-0.945), low effective population sizes (N e = 0.8-50.9), indications of past demographic expansion, and rare long-distance dispersal. Our results are important in implementing conservation strategies for V. uliginosa, which should include founding of seed banks, ex situ cultivations, and reintroductions with individuals of proper origin, combined with continuous population monitoring and habitat management.

High-resolution distribution modeling of a threatened short-range endemic plant informed by edaphic factors

Short-range endemic plants often have edaphic specializations that, with their restricted distributions, expose them to increased risk of anthropogenic extinction.Here, we present a modeling approach to understand habitat suitability for Ricinocarpos brevis R.J.F.Hend. & Mollemans (Euphorbiaceae), a threatened shrub confined to three isolated populations in the semi-arid south-west of Western Australia. The model is a maximum entropy species distribution projection constructed on the basis of physical soil characteristics and geomorphology data at approximately 25 m2 (1 arc-second) resolution.The model predicts the species to occur on shallow, low bulk density soils that are located high in the landscape. The model shows high affinity (72.1% average likelihood of occurrence) for the known populations of R. brevis, as well as identifying likely locations that are not currently known to support the species. There was a strong relationship between the likelihood of R. brevis occurrence and soil moisture content that the model estimated at a depth of 20 cm.We advocate that our approach should be standardized using publicly available data to generate testable hypotheses for the distribution and conservation management of short-range endemic plant species for all of continental Australia.

Features of Dictamnus albus (Rutaceae) in the pregenerative period of ontogeny in M. M. Gryshko National Botanical Garden in Ukraine

Investigation of plant ontogenetic peculiarities and establishment of boundaries of ontogenetic states of individuals is a necessary basis for studying their populations. The minimal amount of data on morphology of plants in the pregenerative period of ontogenesis complicates plant identification in natural and cultural populations. Such information is especially important for rare species of plants. Dictamnus albus L. is a perennial rare plant listed in the Red Book of Ukraine.The objective of this research is to analyze the peculiarities of ontomorphogenesis of D. albus, to establish diagnostic signs of age stages and the sequence of their passage for identification of the multivariance of development. The results of the study on D. albus ontomorphogeny in the latent and pregenerative period at the M. M. Gryshko National Botanical Garden оf the National Academy of Sciences of Ukraine are represented in this article. Diagnostic features of age stages: seeds, seedlings, juvenile, immature, virginile are established. The study shows a multivariate development that reveals different sequences of passing ontogenesis states by individuals and, accordingly, the rate of their aging and life expectancy. To describe the variation of the passage by individuals of ontogeny stages, we divided the stages into ontomorphs, which determined the degree of development-degradation of plants. The research showed that every age stage lasts for one growing season or longer. The first bloom in plants does not come earlier than the sixth year of vegetation. Seedlings and juvenile plants vary in leaf number and phyllotaxy. The development of immature plants takes place from the third year of vegetation. Seedlings, juvenile and young immature plants have a tap-root system. In individuals older than 4 years a root system forms which becomes similar to the fibrous root system due to the presence of several thickened roots. In immature and virginile plants, we observed the formation of adventitious roots on the caudex. It has been found that D. albus is characterized by heterophylly and morphological variability of leaves, which is developed during ontogeny and shoot formation. The variety of the architecture of individuals in the early stages of ontogenesis and the multi-variation of their development indicate the variation of the reaction rate.The data may be used for evaluate age (ontogenetic) structure of D. albus populations.

Conserving plants within and beyond protected areas - still problematic and future uncertain

Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actions employed, clarify the wording of the CBD targets and provide clearer operational guidance as to how they are to be implemented and their implementation monitored. The role and effectiveness of protected areas in conserving biodiversity and in particular plant species in situ are discussed as are recent proposals for a massive increase of their extent. The need for much greater effort and investment in the conservation or protection of threatened species outside protected areas where most plant diversity occurs is highlighted. The difficulties involved in implementing effective in situ conservation of plant diversity both at an area- and species/population-based level are discussed. The widespread neglect of species recovery for plants is noted and the desirability of making a clearer distinction between species recovery and reintroduction is emphasized. Key messages from a global overview of species recovery are outlined and recommendations made, including the desirability of each country preparing a national species recovery strategy. The projected impacts of global change on protected areas and on species conservation and recovery, and ways of addressing them are discussed.

Tree conservation can be constrained by agents from conservation permitting and funding agencies

Recent conservation actions for Serianthes nelsonii Merr. and Cycas micronesica K.D. Hill in the Mariana Islands have illuminated some negative consequences associated with ill-informed agents representing permitting and funding agencies. Several cases from the islands of Guam and Tinian are discussed as ineffective conservation examples, and these are countered with two examples of successful conservation approaches. When biologists that act as points of contact for federal permitting and funding agencies do not possess education, knowledge, and experience that is germane to federally listed species, sound science may be marginalized from the conservation agenda. When rapid turnover of federal conservation agents introduces dysfunction, discontinuities in collaborations may thwart success. When lapses in conservation contracts are allowed, short-term extemporary contracting approaches are utilized, and conservation practitioners that lack the ability to include an experimental approach to conservation actions are employed, the co-production of new knowledge to enable decision support tools for future decision-makers may be hindered.

Securing a future for China's plant biodiversity through an integrated conservation approach

The severely threatened Chinese flora urgently needs a new, well adapted to China and properly formulated conservation strategy. The present review provides a detailed conservation methodology that complements previously described guidelines for preservation of plant species with extremely small populations (PSESP) in China. This review adds to the above concept in several aspects, making it relevant to all threatened Chinese plant species. The proposed integral conservation strategy has the following crucial components:-ecoregional basis for conservation planning and implementation;-a unified scoring system that is used in regional systematic planning for reserve design, monitoring and assessment of efficiency of a reserve network, and creation of seed banks and living collections;-a focus on population demography and the presence of naturally occurring regeneration as the key criteria for defining the conservation status of a species and the appropriate major focus of the species recovery plan;-creation of multi-species living collections that preserve species genetic variation and provide material for in situ actions;-experimental translocation of threatened species into multiple locations within and outside their known range. Adopting and implementing these strategies successfully and more fully in China requires that the country changes PA legislation and improves PA management, the National Science Foundation of China (NSFC) re-prioritizes the type of research that receives research funds, and local scientists improve their approach toward information sharing.