Populations Of Rare Species Research Articles

Field surveys and revegetation experiments show that simulation of topographical habitat features could improve the chances of successful restoration for the threatened succulent Juttadinteria albata

Species with highly restricted ranges are disproportionately at risk of extinction, particularly where habitat loss occurs as a result of mining. Postmining restoration of rare species populations is considered as an appropriate response to counter such threats, but requires a careful, evidence‐based, and information‐driven approach. The economically important diamond mining at Sendelingsdrif in the southern Namib Desert occurs in the highly diverse Succulent Karoo Biome and threatens a significant part of the population of the narrow endemic succulent plant species Juttadinteria albata. To decrease the inherent risks of restoring such a rare species, we studied the habitat features of premining J. albata populations and experimentally tested whether some features could assist future reintroductions in postmining substrates. Plots where J. albata occurred were mostly south‐ to west‐facing and had among others higher rock cover and steeper slopes than plots where J. albata plants were absent. A revegetation experiment, with J. albata cuttings that were established on postmining substrate mounds, revealed that plants on steeper slopes, facing south to west, grew faster than plants on other slopes and aspects. Slope and aspect are therefore important habitat properties to recreate when restoring J. albata populations. These, and other preferred habitat properties such as higher levels of organic C, should now be tested in larger‐scale field trials. Validation of habitat requirements of J. albata through the revegetation experiment has decreased the risks at least partially and provides additional empirical evidence of the importance of establishing reference conditions to enhance ecological restoration.

Impacts of maternal characteristics and temperature on juvenile survival in the crocodile lizard: Implications for conservation.

Captive breeding is an important conservation measure that may restore and enhance wild populations of rare and endangered species. Multiple anthropogenic hazards have brought the crocodile lizard, Shinisaurus crocodilurus, to the brink of extinction. We initiated a captive breeding program and quantified female reproductive traits, including reproductive timing, litter size, litter mass, and neonate size. To identify the internal and external factors affecting female reproductive function, we then analyzed how maternal age is related to body size, temperature, and female reproductive traits. We found that larger female crocodile lizards produced more offspring than smaller ones, as both litter size and litter mass were positively related to maternal body size. In contrast, neonate size was independent of maternal body size. Maternal reproductive output varied among different age groups. Young and old females had significantly smaller living litter size and mass than middle-aged females. Among captive females, one-third exhibited early parturition in autumn and winter instead of the following spring, a pattern probably associated with higher ambient temperatures in captivity. Although female reproductive output and neonatal body size did not differ between early- and normal-parturition females, offspring from the former group died earlier than those from the latter. Our study highlights the danger of climate change in hastening parturition, a phenomenon that could significantly hamper neonate survival and impede population recruitment.

Changes in vitality of populations of rare arctic-alpine plant species in high mountain part of the Ukrainian Carpathians under the influence of climatic factors

Changes in vitality of populations of rare arctic-alpine plant species ( Anemone narcissiflora , Bartsia alpina , Saussurea alpina , Pedicularis oederi ) of the Ukrainian Carpathians in the highland habitats under the influence of climatic factors were analyzed. Population vitality was investigated according to individual diagnostic parameters – vitality of individuals, population vitality index, population quality index, and according to population parameters – density, total and effective quantity. It was established that during 2010–2018, the vitality of the Saussurea alpina population on the Shpyci Mount remained average. The uneven distribution of individuals on habitat area and complex spatial structure of the population loci positively affected the vitality of the Saussurea alpina population on Mt. Shpyci. Individuals of different vitality levels and heterogeneous structure according to morphometric parameters were observed in population. A decrease in population vitality and flowering gaps of generative individuals were observed in Saussurea alpina population on Mt. Petros due to climatic changes, intrapo­pulation processes, and anthropogenic stress. The upper locus of the only population of Pedicularis oederi in Ukraine between Brebeneskul and Munchel mountains underwent transformation, in particular, drying out of suitable habitats due to climate change. The population also underwent periodic anthropogenic influence as a result of grazing, which leads to unstable demographic trends – decrease in the habitat area, number of adults and generative individuals, coefficient of generative reproduction etc. A vitality of the Anemone narcissiflora population behind Nesamovyte Lake remains high. During 2011–2018, the total population size increased due to subsenile and senile individuals, while a number of the pregenerative individuals and the effective population size decreased. An increase in ontogenesis polyvariability, density of individuals, recovery index, number of pregenerative individuals and decrease in number of generative individuals are observed in Bartsia alpina population on Mt. Rebra due to overgrowth of the habitat by highdensity plants and shrub species ( Juncus trifidus , Vaccinium myrtillus and Rhododendron myrtifolium ). Clonal reproduction was intensified. Rejuvenation of populations and a increase in pregenerative phases duration, in particular – immature and virginile periods, were observed.

Типы популяций некоторых редких видов бобовых растений в Самарской области

Типы популяций некоторых редких видов бобовых растений в Самарской области

Distribution and Current State Cenopopulations of <i>Helichrysum maracandicum</i> Popov ex Kirp. in Uzbekistan

The current state of coenotic populations of rare and endangered species of Uzbekistan Helichrysum maracandicum is given. The range of species distribution is broad. The article contains 12 cenopopulations of Helichrysum maracandicum in Uzbekistan, which have considerable healing properties. During the researches, no censorship marks were recorded in any cenopopulation. Approximately, 1, 5, 11 censorpopulations were found to be close to optimal conditions. This indicates that adequate amounts of precipitation in these areas throughout the year have a positive impact on the growth and development of the plant. Most of the cenopopulations were transmitted to younger and transient states.

Ivanovo Region natural monument «Lake Vazal (reservoir in Yuzha)» characteristics

The paper deals with the ecological research of Ivanovo Region natural monument Lake Vazal (reservoir in town Yuzha). The reservoir is located in Yuzha of the Ivanovo Region, it was founded in 1859 by the overlapping a small river Vazovka with dam filling a formed basin with water. This reservoir was named Lake Vazal. The reservoir was recognized as a natural monument of regional value in 1975. The author describes different parameters of the lake and presents a bathymetric schema of the bottom. The relief of the lake banks is characterized. There are sod-shallow podzolic medium-power, medium sod medium- and low-humic sandy soils on the water-ice scurf on the banks of the lake. The water analysis is made. Meadow, marshy, aquatic and hygrophytic plant communities of this protected area are described briefly. The author has registered 277 vascular plant species from 3 divisions, 4 classes, 64 families and 180 genera, among them 3 species (Sanguisorba officinalis, Lembotropis nigricans and Geranium palustre) are included to the Ivanovo Region Red Data Book. 6 species are rare for the region flora. Populations of rare plant species are briefly characterized. Examples of alien and invasion plant species are given. The lake has a great hydrological and environment-forming value and forms a specific microclimate. The square of specially protected natural area is 42 hectares; the square of secured zone is 67,3 hectares.

THE INTRAPOPULATION HETEROSPERMIA OF SOME ORCHID SPECIES

The aim of the work was a comparative morphological study of the peculiarities of the structure of seeds of certain Orchidaceae species from various subfamilies growing on the territory of the mainland Ukraine and Crimea. Methods. In order to carry out the morphological analysis , the seeds were examined on a scanning electron microscope JSM-6060 LA (JEOL, Japan). The size of the structures on the obtained microphotographs was determined using the UTHSCSA Image Tool 3.0 program. The morphometric parameters of the seeds were determined in accordance with the average size of viable seeds for a particular species of orchids. The seed index , the embryo index , and the relative size of the embryo were analyzed. The results of the comparative study of features of the structure of seeds of orchids ( Orchidaceae family) of domestic flora: ( Cephalanthera longifolia (L.) Fritsch., Epipactis palustris (L.) Crantz, Dactylorhiza incarnata (L.) Soo. s.l., Anacamptis coriophora (L.) R.M. Bateman) are presented. The significant heterogeneity of seeds of the studied species is revealed. The morphological analysis established that at the time of dissemination the major part of the studied seeds of orchids were nonviable. Species of orchids with the greatest part of viable seeds with large embryos ( D. incarnata and C. longifolia ) are considered as perspective reintroducents. Conclusion . The results of the research can contribute to the scientific and practical developments aimed at creation of reserve genetic collections in botanical gardens and in reserved areas and also at restitution of a number of natural populations of rare and endangered species.

New locations of rare vascular plant species on cut-over peat lands (on the example of Kirov Region)

The paper presents the investigation data of 6 cut-over peat lands in central area of Kirov Region (on the example of Zuev, Orichev, Slobod, Kirov and Chepez areas). The authors found the new locations of 10 rare plant species enlisted in the regional Red Book and species that have limited distribution in a region or have narrow ecological range (Gymnadenia conopsea, Dactylorhiza fuchsii, Epipactis helleborine, Epipactis atrorubens, Platanthera bifolia, Trichophorum alpinum, Botrychium multifidum, Dryopteris cristata, Thelipteris palustris, Huperzia selago). They also describe the process of phytocoenoses. The study shows the development of new typical boggy plant societies as a result of secondary bogging (on the example of Trichophorum alpinum, Drosera rotundifolia, Carex nigra, Eriophorum vaginatum, Parnassia palustris). The paper estimates the state of rare species populations. The authors analyze the ability of the species to inhabit artificial landscapes and anthropogenically modified phytocoenoses. That shows an explerent component of ecological-phytocoenotic strategy. Secondary boggy landscapes can play the role of refugiums for the species which habitats were lost due to industrial impact.

Considerations for monitoring population trends of colonial waterbirds using the effective number of breeders and census estimates.

Detecting trends in population size fluctuations is a major focus in ecology, evolution, and conservation biology. Populations of colonial waterbirds have been monitored using demographic approaches to determine annual census size (N a). We propose the addition of genetic estimates of the effective number of breeders (N b) as indirect measures of the risk of loss of genetic diversity to improve the evaluation of demographics and increase the accuracy of trend estimates in breeding colonies. Here, we investigated which methods of the estimation of N b are more precise under conditions of moderate genetic diversity, limited sample sizes and few microsatellite loci, as often occurs with natural populations. We used the wood stork as a model species and we offered a workflow that researchers can follow for monitoring bird breeding colonies. Our approach started with simulations using five estimators of N b and the theoretical results were validated with empirical data collected from breeding colonies settled in the Brazilian Pantanal wetland. In parallel, we estimated census size using a corrected method based on counting active nests. Both in simulations and in natural populations, the approximate Bayesian computation (ABC) and sibship assignment (SA) methods yielded more precise estimates than the linkage disequilibrium, heterozygosity excess, and molecular coancestry methods. In particular, the ABC method performed best with few loci and small sample sizes, while the other estimators required larger sample sizes and at least 13 loci to not underestimate N b. Moreover, according to our N b/N a estimates (values were often ≤0.1), the wood stork colonies evaluated could be facing the loss of genetic diversity. We demonstrate that the combination of genetic and census estimates is a useful approach for monitoring natural breeding bird populations. This methodology has been recommended for populations of rare species or with a known history of population decline to support conservation efforts.

Plant life history stage and nurse age change the development of ecological networks in an arid ecosystem

Understanding how ecological networks are organised over the course of an organism's lifetime is crucial for predicting the dynamics of interacting populations and communities across temporal scales. However, most studies so far considered only one life history stage at a time, such as adult, when studying networks of interacting species. Therefore, knowledge about how multiple life history stages affect the development and stability of plant–plant association networks is lacking. We measured the understory adult plant community and the soil seed bank across a plant age gradient of the nurse shrub Retama sphaerocarpa in an arid ecosystem in Spain. Using a multilayer network approach, we built adult understory–nurse and seed bank–nurse networks and analysed how network nestedness, species’ role, and species specificity varied between them and with nurse plant age. We found that seed bank and adult understory networks changed depending on nurse plant age in two different ways. With increasing nurse plant age, adult understory networks became significantly more nested than seed bank networks. The nested architecture of seed bank networks was therefore a poor predictor of adult understory network nestedness. The contribution and specificity of species to network nestedness increased with increasing nurse plant age more in the adult understory than in seed bank networks, despite high species turnover. Our data show that life history and ontogeny affect the development of plant–plant association networks. Niche construction and environmental filtering along nurse ontogeny seem pivotal mechanisms structuring adult understory networks while the assembly of seed bank networks seems rather stochastic. We highlight the importance of mature plant communities for maintaining rare species populations and supporting the stability of ecological communities through time.

Strong fluctuations in aboveground population size do not limit genetic diversity in populations of an endangered biennial species

Assessing genetic diversity within populations of rare species and understanding its determinants are crucial for effective species protection. While a lot is known about the relationships between genetic diversity, fitness, and current population size, very few studies explored the effects of past population size. Knowledge of past population size may, however, improve our ability to predict future population fates. We studied Gentianella praecox subsp. bohemica, a biennial species with extensive seed bank. We tested the effect of current, past minimal and maximal population size, and harmonic mean of population sizes within the last 15years on genetic diversity and fitness. Maximum population size over the last 15years was the best predictor of expected heterozygosity of the populations and was significantly related to current population size and management. Plant fitness was significantly related to current as well as maximum population size and expected heterozygosity. The results suggested that information on past population size may improve our understanding of contemporary genetic diversity across populations. They demonstrated that despite the strong fluctuations in population size, large reductions in population size do not result in immediate loss of genetic diversity and reduction of fitness within the populations. This is likely due to the seed bank of the species serving as reservoir of the genetic diversity of the populations. From a conservation point of view, this suggests that the restoration of small populations of short-lived species with permanent seed bank is possible as these populations may still be genetically diverse.

ONTOGENETIC STRUCTURE AND TYPES OF CENOPOPULATION OF LASER TRILOBUM (L.) BORKH. (APIACEAE) IN THE MIDDLE VOLGA BASIN

The research of this kind will be in demand for a long time when monitoring natural complexes in connection with the poor study of populations of rare species in nature. The purpose of our study is to study the current state of the cenotic populations of the rare species Laser trilobum (L.) Borkh. (Apiaceae) in the Middle Volga basin. The species is included in the Red Data Book of the Samara Region and some other regions. It is confined to oak forests on limestone and marly soils. Some features of the biology and ecology of the species have been studied in other regions. The natural populations of the species are almost not investigated. We studied the structure of 22 cenopopulations of L. trilobum. In the course of the work, populationbased ontogenetic methods were used. The density of individuals is 5.3–26.1 copies per m2 . In the ontogenesis of L. trilobum, the regenerative, generative periods and eight ontogenetic states are distinguished. Senile individuals are not marked. Fluctuation dynamics of ontogenetic composition is characteristic for populations. The average ontogenetic spectrum for the investigated cenopopulations is a single-vertex left-handed with a predominance of virgin individuals. The estimation of populations was carried out by the criterion of “delta-omega” of L. A. Zhivotovsky (2001). Most of the cenopopulations are young, three are mature, one is transient. A significant number of young plants testify to the high capacity of L. trilobum populations to self-repair and maintain. Populations of the model species in the studied habitats are in a satisfactory state. An increase in the anthropogenic load negatively affects the structure and condition of the cenotic populations.

Going extinct before being discovered? New lichen fungi from a small fragment of the vanishing Atlantic Rainforest in Brazil

Abstract In the frame of an ongoing lichen inventory of Atlantic Rainforest remnants in Northeast Brazil, five new species of Graphidaceae were discovered in a small forest fragment, Mata do Cipó, in Sergipe state, the smallest state of Brazil and among those with the highest deforestation rate in the country. An additional new species had already been collected in Panama before and was now also found in the Mata do Cipó and is described here as well. In total, 40 species of Graphidaceae are reported for this remnant, including a large number of taxa indicative of well-preserved rainforest. The new species are: Fissurina atlantica T.A. Pereira, M. Cáceres & Lücking, sp. nov., Graphis subaltamirensis Passos, M. Cáceres & Lücking, sp. nov., Ocellularia cipoensis L.A. Santos, M. Cáceres & Lücking, sp. nov., O. sosma T.A. Pereira, M. Cáceres & Lücking, sp. nov., O. submordenii Lücking, sp. nov. (also known from Panama), and Pseudochapsa aptrootiana M. Cáceres, T.A. Pereira & Lücking, sp. nov. The findings are discussed in the context of the strong fragmentation of the Atlantic Rainforest, with individual remnants apparently serving as refugia for residual populations of rare species of lichen fungi that were more widely distributed in the past, but currently seem to occur only in isolated fragments.

Promising ichthyologic studies in Lake Baikal: fundamental and applied aspects

Promising areas of ichthyologic research in Lake Baikal have been examined. Particular attention is being paid to the technology of remote fsh census, including hydroacoustic methods and the method of quantitative environmental DNA analysis. These technologies may provide information on the status of artifcially reproducible populations in reservoirs for developing a proper fshing strategy. The areas of application of molecular genetic methods for solving applied problems in creating the biological bases of fsheries, studying diseases, associated microflora and parasitic fauna, as well as for identifying fsh feed objects have been determined. Studies aimed at restoring and maintaining the populations of rare and endangered fsh species using artifcial reproduction methods, including breeding, hybridization, hormonal stimulation of spawning producers, cryopreservation of sexual products, individual tagging, etc., are discussed. Prospects of mobile remote underwater video monitoring systems, the EthoStudio software package and the holography method to simulate sensory reaction in studying mechanisms of adaptations of fsh in natural environment and to develop criteria for assessing their stability in aquaculture conditionshave been reviewed. Combining ethological studies and in-depth integrated morphological, molecular-genetic and physiological-biochemical screening of Baikal fsh that would allow to better understand fundamental evolutionary processes responsible for the formation of behavioral adaptations, creation and maintenance of genetic diversity within and between populations in the natural environment, as well as developing recommendations on the introduction of state-of-theart scientifc monitoring approaches into aquaculture are very promising.

The Current State of Cenopopulation of <i>Tulipa micheliana</i> Hoog in Uzbekistan

The current state of coenotic populations of rare and endangered species of Uzbekistan-Tulipa micheliana Hoog is given. Based on the analysis of demographic indicators and a number of organisms and population signs, the state of the cenotic populations of the species was assessed, during the 2012-2018 years studied 15 cenopopulations different ecological-phytocenotic conditions in Uzbekistan.

Coyote diet patterns in the Mojave Desert: implications for threatened desert tortoises

Coyotes (Canis latrans) are generalist predators and are ubiquitous in North America. Occasionally, predation by coyotes can pose a threat to populations of rare species. We assessed diet patterns of coyotes over a 5-year period (2009–14) in a region of the Mojave Desert where high predation rates on threatened desert tortoises (Gopherus agassizii) had been reported. Our goal was to identify primary food items for coyotes and to assess the importance of desert tortoises in the diet. Coyotes primarily consumed rabbits and rodents with rabbits being consumed preferentially and rodents, along with secondary foods including various birds, reptiles, arthropods, and fruits, being consumed more opportunistically. In response to low annual precipitation in the last three years of the study, dietary diversity increased, as did use of anthropogenic food items by coyotes. However, coyotes did not seem to be dependent upon anthropogenic items. Remains of desert tortoises occurred in coyote scats at low frequencies (<6%) in all years and seasons, and use of tortoises appeared to be opportunistic as use varied with tortoise abundance. In the portion of the study area where 571 translocated desert tortoises had been released in 2008, the frequencies of tortoise remains in coyote scats were markedly higher in the two years following the releases (7.5% and 8.8%, respectively). The high predation rates on tortoises reported in this area may have resulted from focussed coyote foraging efforts due to the availability of vulnerable individuals (e.g. disoriented and displaced tortoises) as well as higher tortoise densities.

Species climatic niche explains drought‐induced die‐off in a Mediterranean woody community

AbstractDuring the last decades, plant die‐off has been reported worldwide as a result of increased frequency and intensity of extreme drought events. From a niche perspective, a species performance should decrease as the climatic conditions defining a drought event differ from those characterizing the species climatic niche (the average conditions experienced by the species). Species distribution models (SDMs) can potentially be used to test the link between species performance and their climatic niche by means of climatic suitability indexes. We studied the remaining green canopy of 18 woody species co‐occurring in a Mediterranean shrubland from the central Iberian Peninsula that experienced a severe die‐off following an extreme drought event. We found that the suitability of the climatic conditions estimated by SDMs strongly declined for all species during the extreme drought event. Species die‐off was significantly explained by the decrease in climatic suitability during the event, estimated as the ratio between the historic and the extreme event climatic suitability. Species with high occupancy levels across the landscape exhibited higher die‐off likely because (1) these species have short life‐span and mortality would be compensated by later high recruitment or (2) populations of rare species may have experienced local adaptation to drier conditions. Our results indicate that extreme drought events can have a negative effect, even in shrubland communities living in arid environments. Also, we develop a new approach that connects population‐level responses to species climatic niches through SDMs, and it can be applied to predict community responses to strong climatic variability, such as drought events.

The tendencies in the development of the system of specially protected natural territories of Siberia

An analysis is made of 100 years of development of specially protected natural territories of Siberia. Attention is centered on the characteristic features of territorial nature conservation which are determined by the dependence on the political, economic and managerial factors. The analysis revealed the periods of formation, decline, opposite trends and negative dynamics in the establishment of new protected natural territories. Using the history of reserve management and studies of Russia as an example, it is shown that most innovations were tested in Siberia, starting from the establishment of Russia’s first state zapovedniks and zakazniks and ending with the setting up of joint directorates of specially protected natural territories in recent years. It is pointed out that the approaches in substantiating the system of protected natural areas were characterized by fundamental differences: from the organization of “pristine benchmarks” of nature with the ideology of total non-interference, to “farm zapovedniks” for breeding valuable game animals and active maintenance of the population of rare species accompanied by measures to eliminate “harmful” species. The rivalry between the geographical and biocentric approaches is described: in the former case, the preservation of typical natural systems was dominant; in the latter case, the preservation of rare and endangered species was paramount. It is concluded that the unevenness of distribution of zapovedniks, zakazniks and national and natural parks depends on the degree of development and exploration of a relevant territory, the likelihood of a total disappearance of the most valuable areas, and on the existence of lands of indigenous ethnic groups. It is demonstrated that the process of development of the system of territorial nature conservation is governed by the administrative initiative, consideration for the characteristics of a region’s economic development and changeable institutional conditions as well as by the factors of the country’s foreign and internal policy.

Effective seed harvesting strategies for the ex situ genetic diversity conservation of rare tropical tree populations

Tropical rain forests harbor a high diversity of tree species, a large portion of which are considered rare and threatened by anthropogenic factors such as land-use change. Addressing the global need for ex situ rescue populations of such species, we investigated whether certain methods of wild-source seed collection harvest greater amounts of genetic variation from the source population while minimizing the costs expended. We used an individual-based computer program (NEWGARDEN) to conduct simulation trials examining which aspects of seed procurement provided the most cost-effective methods for maximal rare allele capture for single isolated populations of rare tropical tree species. Aspects examined included the geometric pattern of harvesting, location of seed collections within the spatial distribution of the population (central vs. peripheral), geometric partitioning of sampling regions (contiguous vs. subdivided), gene dispersal distance, linear travelling costs, and ratio of seeds collected to plants sampled. Results demonstrated that ratio of seeds collected to plants sampled had the highest effect on genetic diversity harvested relative to sampling location or geometric pattern of collection, explaining 82 and 79% of the variance in alleles harvested, respectively. Collecting from subdivided peripheral sampling regions and populations having long distance gene dispersal led to increases of up to 39 and 51% in the amount of genetic variation conserved respectively. These results suggest that ex situ conservation efforts for rare tropical trees can benefit by collecting fewer seeds from each of a larger number of trees, sampling from peripheral subdivided regions of the population rather than in a contiguous centrally located one under the transect or nearest neighbor strategies, and adjusting harvesting based on the dispersal biology of the source population. This study underscores the need for more information regarding the dispersal characteristics of the target species and demonstrates the value of predictive modeling for planning seed collection projects.

Analysis of the current status of populations of rare plant species of nature monument Troicki chalk mountains (Orenburg region)

the results are presented for the study of four rare species in the Troicki chalk mountains: Anthemis trotzkiana Claus., Matthiola fragrans Bunge, Lepidium meyeri Claus, and Zygophyllum pinnatum Cham. The total density of the studied coenopopulations ranged from 2.2 to 6.1 copies/m2, and the effective density was 1.5–4.2 copies/m2. Coenopopulations are normally incomplete, most typically lacking the spectrum of seedlings, juvenile and senile individuals, and generative individuals that peak in middle-age. Coenopopulations Anthemis trotzkiana lack postsenile individuals. By the “delta-omega” classification, coenopopulations Anthemis trotzkiana, Matthiola fragrans are growing old, Lepidium meyeri are transitional, and Zygophyllum pinnatum are mature. The indices of recovery and senescence are 0.03–0.36 and 0.03–0.72, respectively. High levels of variability and plasticity of morphometric characters have been registered.