Identifying species at extinction risk using global models of anthropogenic impact

Marine protected areas in the context of climate change: key challenges for coastal social-ecological systems

Climate and ecological emergencies play out acutely in coastal systems with devastating impacts on biodiversity, and the livelihoods of communities and their cultural values. Marine Protected Areas (MPAs) are one of the key management and regulatory tools against biodiversity loss, playing a role in strengthening bio-cultural diversity and sustainability of coastal social-ecological systems. What is unclear though is the effectiveness of static protections under climate change as species move. Next to ecological uncertainty, regulatory uncertainty may play a role in weakening marine conservation. We asked whether MPAs are ecologically effective now and can sustain or improve to be so in the future while facing key climate and regulatory uncertainties. MPAs can support the protection of cultural values and have an impact on activities of sea-users and the sustainability of social-ecological systems. As such, questions surrounding their legitimacy under a changing climate and increased uncertainty are pertinent. We argue that MPA governance must be cognisant of the interdependency between natural and human systems and their joint reaction to climate change impacts based on an integrated, co-developed, and interdisciplinary approach. Focusing on the UK as a case study, we highlight some of the challenges to achieve effective, adaptive and legitimate governance of MPAs. This article is part of the theme issue 'Nurturing resilient marine ecosystems'.

Protected areas in South Asia: Status and prospects

Natural ecosystems globally have been disrupted by anthropogenic activities, and the current biodiversity extinction rate exceeds the natural extinction rate by 1,000-fold. Protected areas (PAs) help insulate samples of biodiversity from these human-induced threats; however, assessments of the factors threatening biodiversity in PAs are scarce in South Asia - one of the key global epicentres of human population growth. Here, by synthesizing published literature and analysing the current configuration of the PA estate, we discuss the trends and biases in existing knowledge, identify research gaps, measure the level of PA coverage and growth patterns, and discuss the threats to South Asian biodiversity inside PAs. We showed that published studies focused mainly on documenting species distributions in PAs, were heavily biased toward vertebrates, and had been mostly conducted in India. Nearly 70% of studies focused on the distribution of organisms, while only 9% performed conservation assessments or devised strategies to manage PAs; 70% of studies cover vertebrates, while only two studies focused on marine fauna; 50% of studies focused on India, with only a handful from Afghanistan. Only three (Bhutan, Nepal, Sri Lanka) of the eight countries already meet a terrestrial PA representation target of 17%, while no country meets a marine representation target of 10%. Most PAs were very small, with nearly 80% below 100 km², and 22% below 1 km². We identified that South Asian PAs are facing a broad range of anthropogenic threats - about three in five studies reported threats inside protected areas. Due to extensive anthropogenic pressures, biodiversity in South Asia is facing an existential crisis, and society-wide collaborative efforts are needed to arrest and reverse the declines. We hope this review will stimulate efforts to capitalise on the opportunity for efficient PA growth in the region on the eve of the post-2020 global biodiversity targets.

The danger and indeterminacy of forfeiting perching space of bryophytes from climate shift: a case study for 115 species in China

Identifying the danger and expressing the indeterminacy of forfeiting perching space of species induced by rapid climate warming is crucial for biodiversity risk management under future changes in climate conditions. The scenarios of climate shift named the representative concentration pathways, the categorizing technique with regard to fuzzy-set, and Monte Carlo scheme was employed to survey the indeterminacy and the danger of forfeiting perching space caused by climate warming for 115 bryophytes in China. For the deterministic scenarios of climate shift, the richness of 115 bryophytes improved in several areas in north-eastern China, while it dropped in some areas in southern, eastern, south-eastern, and central China. In addition, for the deterministic scheme of altering climatic state, the count for bryophytes with the proportion of contracting the present areal range as less than 20%, 20-40%, 40-60%, 60-80%, and over 80% was belike 34-38, 19-38, 24-35, 9-19, and 4-9, separately; the count of bryophytes with the ratio of the occupying entire areal range as over 80%, 60-80%, and less than 20% was roughly 97-109, 4-14, and 2-8, separately. For the scenarios of randomly change in climate state, the number of bryophytes with a various proportion of forfeiting the present perching space dropped with enhancing the possibility; with the likelihood beyond 0.6, the count of bryophytes with forfeiting present perching space as less than 20%, 20-40%, 40-60%, 60-80% and high than 80% of the present areal range was approximately 7-14, 2-10, 0-7, 2-9, and 13-20, separately; the number of bryophytes with the ratio of occupying the whole areal range as less than 20%, 20-40%, 40-60%, 60-80%, and over 80% was more or less 1-3, 0-3, 1-5, 1-3, and 38-44, separately. Roughly 48 bryophytes would face the risk of extinction from climate warming, including endemic and non-endemic species. Forfeiting perching space induced by climate warming would cause variations in species composition and the disappearance of some ecological functions associated with these bryophytes. The inconstancy of forfeiting areal range caused by climate warming should be incorporated into the policy-making of conservation bryophytes for adaptation of climate warming.

Genetic management on the brink of extinction: sequencing microsatellites does not improve estimates of inbreeding in wild and captive Vancouver Island marmots (Marmota vancouverensis)

Captive breeding is often a last resort management option in the conservation of endangered species which can in turn lead to increased risk of inbreeding depression and loss of genetic diversity. Thus, recording breeding events via studbook for the purpose of estimating relatedness, and facilitating mating pair selection to minimize inbreeding, is common practice. However, as founder relatedness is often unknown, loss of genetic variation and inbreeding cannot be entirely avoided. Molecular genotyping is slowly being adopted in captive breeding programs, however achieving sufficient resolution can be challenging in small, low diversity, populations. Here, we evaluate the success of the Vancouver Island marmot (Marmota vancouverensis; VIM; among the worlds most endangered mammals) captive breeding program in preventing inbreeding and maintaining genetic diversity. We explored the use of high-throughput amplicon sequencing of microsatellite regions to assay greater genetic variation in both captive and wild populations than traditional length-based fragment analysis. Contrary to other studies, this method did not considerably increase diversity estimates, suggesting: (1) that the technique does not universally improve resolution, and (2) VIM have exceedingly low diversity. Studbook estimates of pairwise relatedness and inbreeding in the current population were weakly, but positively, correlated to molecular estimates. Thus, current studbooks are moderately effective at predicting genetic similarity when founder relatedness is known. Finally, we found that captive and wild populations did not differ in allelic frequencies, and conservation efforts to maintain diversity have been successful with no significant decrease in diversity over the last three generations.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10592-022-01429-7.

The risk of forfeiting the ranges of reptiles under nonrandom and stochastic scenarios of moving climate conditions: a case study for 115 species in China

Revealing the hazard features of forfeiting areal ranges for nonidentical scenarios of shifting climatic conditions is pivotal for the conformation of reptiles to climatic warming. Taking 115 reptiles in China as an example, the indefiniteness and danger of shrinking geographical range for the reptiles under stochastic and nonrandom scenarios of moving climatic situations were inspected via exploiting the scenarios of shifting climatic status associated with the representative concentration pathways, Monte Carlo simulation, and the classifications scheme based on the fuzzy set. For non-stochastic states of altering climatic elements, the richness of 115 reptiles improved in certain sites of northeastern, and western China and dropped in several areas of northern, eastern, central China, and southeastern China: roughly 59-74 reptiles forfeiting less than 20% of their present ranges, roughly 25-34 reptiles narrowing less than 20-40% of their present areal ranges, and roughly 105-111 reptiles inhabited more than 80% of their overall areal ranges. For the random status of shifting climatic elements, the count of reptiles that forfeited the various extent of the present or entire areal ranges descended with raising the eventuality; with a possibility of over 0.6, the count of reptiles that minified less than 20%, 20-40%, 40-60%, 60-80% and over 80% of the present ranges was roughly 28-49, 5-10, 1-3, 0-1 and 13-18, separately; the count of reptiles that inhabited below 20%, 20-40%, 40-60%, 60-80% and more than 80% of the entire real ranges was roughly 0-1, 5-6, 1-5, 0-2 and 35-36, separately. About 30% of 115 reptiles would face disappearance danger in response to moving climate conditions in the absence of adaption steps, and the conformation measures were indispensable for the reptiles that shrunk their areas.

Risk and Uncertainty of Losing Suitable Habitat Areas Under Climate Change Scenarios: A Case Study for 109 Gymnosperm Species in China

Taking 109 gymnosperm species in China as a case, the uncertainty and risk of losing habitat areas of gymnosperm species under future climate conditions were investigated via representative concentration pathways climate change scenarios, fuzzy set classifications and Monte Carlo techniques. Under nonrandom climate change scenarios, the richness of 109 species increased in the partial locations of northwestern and northeastern China and declined in the partial locations of eastern and central and southeastern China; the numbers of species that losing <20%, 20-40%, 40-60%, 60-80%, and over 80% of their current habitat areas were ~33-49, 36-40, 11-24, 7-9, and 2-8, respectively; ~99-105 species occupied over 80% of their total suitable areas and ~4-9 species occupied 60-80% their total suitable areas. Under random climate change scenarios, the number of species that losing various level of the habitat areas declined with enhancing probability; with a probabilities of over 0.6, the numbers of species that losing <20%, 20-40%, 40-60%, 60-80% and over 80% of their current habitat areas were ~19-28, 3-19, 0-3, 1-2, and 9-14, respectively, and the numbers of species that occupying ~20%, 20-40%, 40-60%, 60-80%, and over 80% of their total suitable areas were ~9-14, 4-11, 2-6, 1-3, and 34-45, respectively. Approximately 41% of 109 species will face extinction risks from climate change; the losing habitat areas in future climate condition will cause the varying of coniferous forest composition and the losing of ecosystem service related to the species; the uncertainty of losing distribution areas for species should not be ignored.

Implications of the prevalence and magnitude of sustained declines for determining a minimum threshold for favourable population size

We propose a new approach to quantifying a minimum threshold value for the size of an animal population, below which that population might be categorised as having unfavourable status. Under European Union law, the concept of Favourable Conservation Status requires assessment of populations as having favourable or unfavourable status, but quantitative methods for such assessments have not yet been developed. One population threshold that is well established in conservation biology is the minimum viable population (MVP) defined as the size of a small but stable population with an acceptably low risk of extinction within a specified period. Our approach combines this small-population paradigm MVP concept with a multiplier, which is a factor by which the MVP is multiplied to allow for the risk of a sustained future decline. We demonstrate this approach using data on UK breeding bird population sizes. We used 43-year time-series data for 189 species and a qualitative assessment of population trends over almost 200 years for 229 species to examine the prevalence, duration and magnitude of sustained population declines. Our study addressed the problem of underestimation of the duration and magnitude of declines caused by short runs of monitoring data by allowing for the truncation of time series. The multiplier was derived from probability distributions of decline magnitudes within a given period, adjusted for truncation. Over a surveillance period of 100 years, we estimated that there was a 10% risk across species that a sustained population decline of at least sixteen-fold would begin. We therefore suggest that, in this case, a factor of 16 could be used as the multiplier of small-population MVPs to obtain minimum threshold population sizes for favourable status. We propose this 'MVP Multiplier' method as a new and robust approach to obtaining minimum threshold population sizes which integrates the concepts of small-population and declining-population paradigms. The minimum threshold value we propose is intended for use alongside a range of other measures to enable overall assessments of favourable conservation status.

Land-use conflicts between biodiversity conservation and extractive industries in the Peruvian Andes

The exceptional endemic species richness found in the Tropical Andes is being subjected to high rates of environmental degradation and natural resources exploitation. While many forms of land-cover change and other impacts on species are difficult to control through environmental regulations, governments usually determine how and where extractive industries can take place. This study examines potential conflict between the location of extractive industry activities and biodiversity conservation in the Peruvian Andes. Using geographic information systems, we carry out overlay analyses to determine the spatial congruence between mineral mining, hydrocarbon and logging concessions, on the one hand, and the distribution of protected areas and endemic vertebrate species on the other. The results show that regional protected areas extensively overlap with resource concessions. Furthermore, 16% of endemic species hotspots concur with current concessions, while the geographical distribution of 21 endemic vertebrate species overlap by more than 90% with concession areas. To reconcile conservation and economic development objectives in the future, the geographical distribution of biodiversity, and in particular of endemic species, needs to be considered in natural resources planning and land-use/management activities.

Predicted extinction of unique genetic diversity in marine forests of Cystoseira spp

Climate change is inducing shifts in species ranges across the globe. These can affect the genetic pools of species, including loss of genetic variability and evolutionary potential. In particular, geographically enclosed ecosystems, like the Mediterranean Sea, have a higher risk of suffering species loss and genetic erosion due to barriers to further range shifts and to dispersal. In this study, we address these questions for three habitat-forming seaweed species, Cystoseira tamariscifolia, C. amentacea and C. compressa, throughout their entire ranges in the Atlantic and Mediterranean regions. We aim to 1) describe their population genetic structure and diversity, 2) model the present and predict the future distribution and 3) assess the consequences of predicted future range shifts for their population genetic structure, according to two contrasting future climate change scenarios. A net loss of suitable areas was predicted in both climatic scenarios across the range of distribution of the three species. This loss was particularly severe for C. amentacea in the Mediterranean Sea (less 90% in the most extreme climatic scenario), suggesting that the species could become potentially at extinction risk. For all species, genetic data showed very differentiated populations, indicating low inter-population connectivity, and high and distinct genetic diversity in areas that were predicted to become lost, causing erosion of unique evolutionary lineages. Our results indicated that the Mediterranean Sea is the most threatened region, where future suitable Cystoseira habitats will become more limited. This is likely to have wider ecosystem impacts as there is a lack of species with the same ecological niche and functional role in the Mediterranean. The projected accelerated loss of already fragmented and disturbed populations and the long-term genetic effects highlight the urge for local scale management strategies that sustain the capacity of these habitat-forming species to persist despite climatic impacts while waiting for global emission reductions.

Regional and local environmental conditions do not shape the response to warming of a marine habitat-forming species

The differential response of marine populations to climate change remains poorly understood. Here, we combine common garden thermotolerance experiments in aquaria and population genetics to disentangle the factors driving the population response to thermal stress in a temperate habitat-forming species: the octocoral Paramuricea clavata. Using eight populations separated from tens of meters to hundreds of kilometers, which were differentially impacted by recent mortality events, we identify 25 °C as a critical thermal threshold. After one week of exposure at this temperature, seven of the eight populations were affected by tissue necrosis and after 30 days of exposure at this temperature, the mean % of affected colonies increased gradually from 3 to 97%. We then demonstrate the weak relation between the observed differential phenotypic responses and the local temperature regimes experienced by each population. A significant correlation was observed between these responses and the extent of genetic drift impacting each population. Local adaptation may thus be hindered by genetic drift, which seems to be the main driver of the differential response. Accordingly, conservation measures should promote connectivity and control density erosion in order to limit the impact of genetic drift on marine populations facing climate change.

Environmental gap analysis to prioritize conservation efforts in eastern Africa

Countries in eastern Africa have set aside significant proportions of their land for protection. But are these areas representative of the diverse range of species and habitats found in the region? And do conservation efforts include areas where the state of biodiversity is likely to deteriorate without further interventions? Various studies have addressed these questions at global and continental scales. However, meaningful conservation decisions are required at finer geographical scales. To operate more effectively at the national level, finer scale baseline data on species and on higher levels of biological organization such as the eco-regions are required, among other factors. Here we adopted a recently developed high-resolution potential natural vegetation (PNV) map for eastern Africa as a baseline to more effectively identify conservation priorities. We examined how well different potential natural vegetations (PNVs) are represented in the protected area (PA) network of eastern Africa and used a multivariate environmental similarity index to evaluate biases in PA versus PNV coverage. We additionally overlaid data of anthropogenic factors that potentially influence the natural vegetation to assess the level of threat to different PNVs. Our results indicate substantial differences in the conservation status of PNVs. In addition, particular PNVs in which biodiversity protection and ecological functions are at risk due to human influences are revealed. The data and approach presented here provide a step forward in developing more transparent and better informed translation from global priorities to regional or national implementation in eastern Africa, and are valid for other geographic regions.