Journal articles: 'Population Viability Assessment'

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Lee, Danny C., and Bruce E. Rieman. "Population Viability Assessment of Salmonids by Using Probabilistic Networks." North American Journal of Fisheries Management 17, no. 4 (November 1997): 1144–57. http://dx.doi.org/10.1577/1548-8675(1997)017<1144:pvaosb>2.3.co;2.

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Andersen, Mark C. "Potential Applications of Population Viability Analysis to Risk Assessment for Invasive Species." Human and Ecological Risk Assessment: An International Journal 11, no. 6 (December 2005): 1083–95. http://dx.doi.org/10.1080/10807030500278610.

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Mazaris, Antonios D., Øyvind Fiksen, and Yiannis G. Matsinos. "Using an individual-based model for assessment of sea turtle population viability." Population Ecology 47, no. 3 (August 5, 2005): 179–91. http://dx.doi.org/10.1007/s10144-005-0220-5.

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McCallum, Hamish. "Risk assessment in conservation biology." Pacific Conservation Biology 1, no. 4 (1994): 372. http://dx.doi.org/10.1071/pc940372.

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Population viability analysis (PVA) has become one of the standard tools of conservation biology. Unfortunately, few examples have entered the refereed literature. Most remain in the "grey" world of internal government reports, where the results of "what-if" scenarios become transformed into the firm basis for policy settings. The problem is that rough guesses of population parameters enter the black box of a modeling package, to emerge as attractive and apparently precise graphs of extinction probability as a function of population size. Somewhere in the process, it is often forgotten that the quantitative predictions cannot be better than the quality of the parameters which went into them.

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Mirzayans, Razmik, Bonnie Andrais, and David Murray. "Viability Assessment Following Anticancer Treatment Requires Single-Cell Visualization." Cancers 10, no. 8 (August 1, 2018): 255. http://dx.doi.org/10.3390/cancers10080255.

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A subset of cells within solid tumors become highly enlarged and enter a state of dormancy (sustained proliferation arrest) in response to anticancer treatment. Although dormant cancer cells might be scored as “dead” in conventional preclinical assays, they remain viable, secrete growth-promoting factors, and can give rise to progeny with stem cell-like properties. Furthermore, cancer cells exhibiting features of apoptosis (e.g., caspase-3 activation) following genotoxic stress can undergo a reversal process called anastasis and survive. Consistent with these observations, single-cell analysis of adherent cultures (solid tumor-derived cell lines with differing p53 status) has demonstrated that virtually all cells—irrespective of their size and morphology—that remain adherent to the culture dish for a long time (weeks) after treatment with anticancer agents exhibit the ability to metabolize 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl- tetrazolium bromide (MTT). The purpose of this commentary is to briefly review these findings and discuss the significance of single-cell (versus population averaged) observation methods for assessment of cancer cell viability and metabolic activity.

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Trisurat, Yongyut, Anak Pattanavibool, George A. Gale, and David H. Reed. "Improving the viability of large-mammal populations by using habitat and landscape models to focus conservation planning." Wildlife Research 37, no. 5 (2010): 401. http://dx.doi.org/10.1071/wr09110.

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Context. Assessing the viability of animal populations in the wild is difficult or impossible, primarily because of limited data. However, there is an urgent need to develop methods for estimating population sizes and improving the viability of target species. Aims. To define suitable habitat for sambar (Cervus unicolor), banteng (Bos javanicus), gaur (Bos gaurus), Asian elephant (Elephas maximus) and tiger (Panthera tigris) in the Western Forest Complex, Thailand, and to assess their current status as well as estimate how the landscape needs to be managed to maintain viable populations. Methods. The present paper demonstrates a method for combining a rapid ecological assessment, landscape indices, GIS-based wildlife-habitat models, and knowledge of minimum viable population sizes to guide landscape-management decisions and improve conservation outcomes through habitat restoration. Key results. The current viabilities for gaur and elephant are fair, whereas they are poor for tiger and banteng. However, landscape quality outside the current distributions was relatively intact for all species, ranging from moderate to high levels of connectivity. In addition, the population viability for sambar is very good under the current and desired conditions. Conclusions. If managers in this complex wish to upgrade the viabilities of gaur, elephant, tiger and banteng within the next 10 years, park rangers and stakeholders should aim to increase the amount of usable habitat by ~2170 km2 or 17% of existing suitable habitats. The key strategies are to reduce human pressures, enhance ungulate habitats and increase connectivity of suitable habitats outside the current distributions. Implications. The present paper provides a particularly useful method for managers and forest-policy planners for assessing and managing habitat suitability for target wildlife and their population viability in protected-area networks where knowledge of the demographic attributes (e.g. birth and death rates) of wildlife populations are too limited to perform population viability analysis.

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Shrader‐Frechette, Kristin. "Comparativist Philosophy of Science and Population Viability Assessment in Biology: Helping Resolve Scientific Controversy." Philosophy of Science 73, no. 5 (December 2006): 817–28. http://dx.doi.org/10.1086/518634.

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Rezaeinejad, Saeid, and Volodymyr Ivanov. "Assessment of correlation between physiological states of Escherichia coli cells and their susceptibility to chlorine using flow cytometry." Water Supply 13, no. 4 (August 1, 2013): 1056–62. http://dx.doi.org/10.2166/ws.2013.083.

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The physiological differences of individual cells of bacterial population may imply the existence of cell subpopulations with different sensitivity to chlorine, which may affect the efficiency of drinking water disinfection. The susceptibility of individual bacterial cells to chlorine was examined using flow cytometry. The inactivation of Escherichia coli cells by chlorine in the populations with specific growth rates of 0.2 and 0.9 h−1 was assessed using various viability indicators. Viability of bacterial cells was evaluated using membrane integrity propidium iodide (PI) dye, respiratory activity indicator of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) and membrane potential probe of DiBAC4(3). It was found that there were cell subpopulations of E. coli with different levels of susceptibility to chlorine. E. coli cell population with higher specific growth rate was more susceptible to chlorine. The CT values for inactivation of 99% of cells (CT99) in populations of E. coli with specific growth rates of 0.9 and 0.2 h−1 were 0.06 and 0.09 mg min l−1, respectively. Flow cytometry could be used to study the sensitivity of bacterial cells to the chemical agents.

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King, Tony, Christelle Chamberlan, and Amos Courage. "Assessing reintroduction success in long-lived primates through population viability analysis: western lowland gorillas Gorilla gorilla gorilla in Central Africa." Oryx 48, no. 2 (October 21, 2013): 294–303. http://dx.doi.org/10.1017/s0030605312001391.

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AbstractThe use of population modelling has become an increasingly common tool in reintroduction planning and assessment. Although initial reintroduction success is often measured by quantifying post-release survival and reproduction, longer-term success is best assessed through measurements of population viability. Here we develop a population model capable of providing useful results for influencing management of a reintroduction programme for a long-lived and slow-reproducing primate, the western lowland gorilla Gorilla gorilla gorilla. We used post-release monitoring data from two reintroduced populations in the Batéké Plateau region of Congo and Gabon, complemented with published data on wild and captive populations, to develop a population model using Vortex. Sensitivity testing illustrated that the model was highly sensitive to changes in the input parameters for annual birth rates, the number of lethal equivalents, and for female annual mortality rates, especially for adults. The results of the population viability analysis suggested that the reintroduced gorilla populations have a reasonable chance of persistence (> 90% over 200 years) but illustrated that reinforcement of the populations could significantly improve probabilities of population persistence and retention of genetic diversity. Equally, catastrophic events could have significant negative impacts. Continued monitoring of the populations should allow refinement of the model, improving confidence in its predictions and its relevance to decision-making.

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Murray, Dennis L., Karen F. Hussey, Laura A. Finnegan, Stacey J. Lowe, Glynis N. Price, John Benson, Karen M. Loveless, et al. "Assessment of the status and viability of a population of moose (Alces alces) at its southern range limit in Ontario." Canadian Journal of Zoology 90, no. 3 (March 2012): 422–34. http://dx.doi.org/10.1139/z2012-002.

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Factors affecting the distribution and abundance of animals are of substantial interest, and across most of their southern range, populations of moose ( Alces alces (L., 1758)) are declining, presumably because of climate change. Conditions favouring moose population decline versus numerical increase in select areas of the range are not well understood. During 2006–2009, we tested the hypothesis that moose in southern Ontario formed a viable population near the species’ southern range limit, despite occurrence of climate patterns apparently deleterious for population growth. Our study upheld each of our predictions: (i) high pregnancy rate (83.0%) and annual female survival rate (0.899 (0.859, 0.941; 95% CI)), indicating that the population was increasing (λ = 1.16); (ii) female moose having blood-based condition indices within normal range, despite larger than expected home-range size; and (iii) levels of genetic differentiation indicating that the population was part of a larger metapopulation of moose in the region. We surmise that moose in southern Ontario currently are not subject to the prevalent continental decline, likely owing to favourable site-specific climatic conditions. Future research should elaborate on why select southern moose populations are increasing and whether they will ultimately succumb to die off as effects of climate change become increasingly pronounced.

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Patterson, Brent R., and Dennis L. Murray. "Flawed population viability analysis can result in misleading population assessment: A case study for wolves in Algonquin park, Canada." Biological Conservation 141, no. 3 (March 2008): 669–80. http://dx.doi.org/10.1016/j.biocon.2007.12.010.

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Steventon, J. Douglas, Glenn D. Sutherland, and Peter Arcese. "A population-viability-based risk assessment of Marbled Murrelet nesting habitat policy in British Columbia." Canadian Journal of Forest Research 36, no. 12 (December 1, 2006): 3075–86. http://dx.doi.org/10.1139/x06-198.

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The Marbled Murrelet (Brachyramphus marmoratus Gmelin) is a small threatened seabird of the Pacific coast of North America. Through simulation modelling we varied the long-term minimum amounts and quality (nesting density) of old-forest nesting habitat to examine effects on murrelet population viability, our measure of population resilience. Applying diffusion approximations we estimated population longevity and persistence probability under uncertainties of at-sea demography and onshore edge effects affecting nesting success, time scale, spatial scale, and subpopulation structure. We cast our analysis in a Bayesian belief and decision network framework. We also applied the framework to spatially explicit land-use and murrelet inventory data for the northern mainland region of the British Columbia coast. We found a diminishing expected value of persistence probability (EVP), for a single independent population, below a nesting capacity of ≈5000 nesting pairs (≈15 000 birds), accelerating below 2000 pairs. A strategy of multiple semi-independent subpopulations provided a higher joint EVP across a wide range of total nesting capacity. There was little improvement in EVP, for any number of subpopulations, above 10 000 – 12 000 pairs (≈36 000 birds, 45%–60% of coastwide population estimate in 2001). Depending on estimates of nesting density, 12 000 pairs would require between 0.6 and 1.2 million ha of potential old-forest nesting habitat.

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Ben-Ami, Dror, Daniel Ramp, and David B. Croft. "Population viability assessment and sensitivity analysis as a management tool for the peri-urban environment." Urban Ecosystems 9, no. 3 (July 14, 2006): 227–41. http://dx.doi.org/10.1007/s11252-006-9353-3.

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Bradford, Kent J. "Population-based Models of Seed Viability Loss during Storage: What's the Use?" HortScience 30, no. 4 (July 1995): 910C—910. http://dx.doi.org/10.21273/hortsci.30.4.910c.

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In 1981, R.H. Ellis and E.H. Roberts published a classic paper on the quantification of aging and survival in seeds (Seed Sci. & Technol. 9:373). This paper and subsequent refinements described a model of seed aging in storage that was based on the fact that to a good approximation, deaths over time in a seed population are normally distributed. The model provides a quantitative description of seed longevity across a wide range of storage temperatures and moisture contents. Despite its theoretical importance and practical success, the Ellis–Roberts approach has not been widely adopted by the seed industry to assess seed quality and predict longevity in storage. This may be due, in part, to the rather unfamiliar statistics (probit analysis) used in the model and the apparent complexity of the equations. It will be the argument of this presentation, however, that the precise quantification of seed longevity that this model affords is less significant than the insight that it provides into the nature of seed populations and how to think about them. The objective of this presentation will be to demystify the Ellis–Roberts model and illustrate with concrete examples how the application of population-based thinking is advantageous in many aspects of seed storage and quality assessment.

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Rasmussen, Josh E., and Evan S. Childress. "Population Viability of Endangered Lost River Sucker and Shortnose Sucker and the Effects of Assisted Rearing." Journal of Fish and Wildlife Management 9, no. 2 (December 1, 2018): 582–92. http://dx.doi.org/10.3996/032018-jfwm-018.

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Abstract The Lost River Sucker Deltistes luxatus and Shortnose Sucker Chasmistes brevirostris are two narrowly endemic fish species in the upper Klamath Basin of southern Oregon and northern California. Both species have been federally listed as endangered pursuant to the U.S. Endangered Species Act since 1988 because of dramatic declines in abundance and distribution. In Upper Klamath Lake, Oregon, both species have only recruited a single cohort to the adult populations since that time. Most individuals in this population are at or older than the expected life span of the species. Consequently, the U.S. Fish and Wildlife Service and the Klamath Tribes have initiated assisted rearing efforts to stabilize the population. However, it is unclear how quickly these populations might become extirpated and how assisted rearing might alter population trajectories. We modeled the potential for extinction and recovery of the populations of endangered Lost River Sucker and Shortnose Sucker in Upper Klamath Lake. We simulated population trajectories over the next 50 y with a stochastic population viability assessment approach. Projections indicate that if population trajectories do not change, the Shortnose Sucker population may decline by 78% to number < 5,000 in 10 y and become completely extirpated within the next 30 (18.6% probability) to 40 y (99% probability). The two Lost River Sucker populations have a greater likelihood to remain extant after 50 y, with only 1% probability of extinction given our scenarios and assumptions, but the populations are likely to number fewer than 1,000 individuals. Our results also suggest that rearing of Klamath Lake sucker species in a controlled environment for augmenting the natural population will be effective in reducing extirpation probabilities over the next 50 y if survival to recruitment can be achieved, but a long-term effort of at least 40 y will be required. The necessity of long-term augmentation to ensure population persistence in the absence of natural recruitment underscores the urgent need to determine and address the causes of recruitment failure in the wild.

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Galbraith, Heather S., William A. Lellis, Jeffrey C. Cole, Carrie J. Blakeslee, and Barbara St. John White. "Population Demographics for the Federally Endangered Dwarf Wedgemussel." Journal of Fish and Wildlife Management 7, no. 2 (September 1, 2016): 377–87. http://dx.doi.org/10.3996/112014-jfwm-084.

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Abstract The dwarf wedgemussel Alasmidonta heterodon is a federally endangered freshwater mussel species inhabiting several Atlantic Slope rivers. Studies on population demographics of this species are necessary for status assessment and directing recovery efforts. We conducted qualitative and quantitative surveys for dwarf wedgemussel in the mainstem Delaware River and in four of its tributaries (Big Flat Brook, Little Flat Brook, Neversink River, and Paulinskill River). We quantified population range, relative abundance, size, size structure, and sex ratio within each river. We estimated total dwarf wedgemussel population size for the surveyed rivers in the Delaware Basin to be 14,432 individuals (90% confidence limits, 7,961–26,161). Our results suggest that the historically robust Neversink River population has declined, but that this population persists and substantial populations remain in other tributaries. Sex ratios were generally female-biased, and small individuals (<10 mm) found in all rivers indicate recent recruitment. We most often found dwarf wedgemussel at the surface of the sediment (not buried below) in shallow quadrats (<2.00 m) comprised of small substrate (sand in tributaries; cobble in the mainstem) and minimal aquatic macrophytes. Long-term monitoring, continued surveys for new populations, and assessments of reproductive success are needed to further understand dwarf wedgemussel viability within the Delaware River basin.

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Kafley, Hemanta, Matthew E. Gompper, Madhav Khadka, Mandira Sharma, Rupak Maharjan, and Bishnu Prasad Thapaliya. "Analysis of rhino (Rhinoceros unicornis)population viability in Nepal: impact assessment of antipoaching and translocation strategies." Zoology and Ecology 25, no. 4 (October 2, 2015): 288–94. http://dx.doi.org/10.1080/21658005.2015.1090118.

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Markina, T. Y. "New approaches to quality control for cultures of insects for rearing." Biosystems Diversity 24, no. 1 (March 4, 2016): 164–72. http://dx.doi.org/10.15421/011620.

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An analytical review of existing methods of quality control for cultures of insects for rearing is presented. It is shown that there is a need to search for new approaches to solving this problem. The suggested methods for quality control for insect cultures are based on the rule of taxis intensity dependence on insect viability level. Testing of new methods of control and prediction of biological material viability was carried out on several breeds of silkworm (Bombyx mori L.) and a laboratory culture of the gypsy moth (Lymantria dispar L.). It was established that the caterpillars of silkworm breeds with high viability show higher chemotaxis intensity. It was found that intensity of taxis manifestation can be considered as a criterion of population condition. Selection of the most promising breeds of silkworm can be carried out at the moment of hatching without expensive rearing. It was shown that testing of neonate caterpillars by chemotaxis intensity provides the control of viability in all stages of insect development. Evaluation of chemotaxis intensity of adult males on female sex pheromone gives the possibility to select the specimens with the highest physiological properties for hybridization as well as to predict viability for progeny. The method of biological material selection by chemotaxis intensity was improved due to decrease the time of selection from 30 to 15 minutes and preliminary starvation of these insects. Positive correlation was evaluated between general viability of silkworm culture and intensity of chemotaxis of neonate larvae to the smell of mulberry leaf during 15 minutes after 12 hours of starvation. A significant increase of viability for silkworm breeds and hybrids was registered using such selection method during the spring and summer rearing. This selection method can be used also for assessment of culture viability. A new express-method of biological material selection for insect cultures establishment has been approbated. It is based on the positive correlation between insect viability parameters and their trophotaxis intensity. It is shown that for establishment of a laboratory culture of gypsy moth it is necessary to obtain the material from populations with the highest chemotaxis intensity. It was experimentally proved that parameters of chemotaxis intensity and insect viability reflect a certain level of population heterozygosity. The higher is the intensity of chemotaxis, the higher is the relative level of population heterozygosity. This fact gives the possibility to determine the level of heterozygosity for artificial insect populations by testing larvae for chemotaxis intensity. This method may be suitable for monitoring of natural populations condition in zones with intensive anthropogenic loading.

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Amor, Kaouther Ben, Pieter Breeuwer, Patrick Verbaarschot, Frank M. Rombouts, Antoon D. L. Akkermans, Willem M. De Vos, and Tjakko Abee. "Multiparametric Flow Cytometry and Cell Sorting for the Assessment of Viable, Injured, and Dead Bifidobacterium Cells during Bile Salt Stress." Applied and Environmental Microbiology 68, no. 11 (November 2002): 5209–16. http://dx.doi.org/10.1128/aem.68.11.5209-5216.2002.

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ABSTRACT Using a flow cytometry-based approach, we assessed the viability of Bifidobacterium lactis DSM 10140 and Bifidobacterium adolescentis DSM 20083 during exposure to bile salt stress. Carboxyfluorescein diacetate (cFDA), propidium iodide (PI), and oxonol [DiBAC4(3)] were used to monitor esterase activity, membrane integrity, and membrane potential, respectively, as indicators of bacterial viability. Single staining with these probes rapidly and noticeably reflected the behavior of the two strains during stress exposure. However, the flow cytometry results tended to overestimate the viability of the two strains compared to plate counts, which appeared to be related to the nonculturability of a fraction of the population as a result of sublethal injury caused by bile salts. When the cells were simultaneously stained with cFDA and PI, flow cytometry and cell sorting revealed a striking physiological heterogeneity within the stressed bifidobacterium population. Three subpopulations could be identified based on their differential uptake of the probes: cF-stained, cF and PI double-stained, and PI-stained subpopulations, representing viable, injured, and dead cells, respectively. Following sorting and recovery, a significant fraction of the double-stained subpopulation (40%) could resume growth on agar plates. Our results show that in situ assessment of the physiological activity of stressed bifidobacteria using multiparameter flow cytometry and cell sorting may provide a powerful and sensitive tool for assessment of the viability and stability of probiotics.

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FERNANDES, JOÃO PAULO. "DATA TYPE AND SCALE EFFECTS ON AN EIA PROCESS — CONTEXT VERSUS OBJECT APPROACH: A CASE STUDY OF THE EVALUATION OF THE IMPACTS OF THE A2 ROAD IN SOUTHERN PORTUGAL ON THE IBERIAN LYNX." Journal of Environmental Assessment Policy and Management 02, no. 01 (March 2000): 19–41. http://dx.doi.org/10.1142/s1464333200000047.

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The use of two scales within an environmental impact assessment study of the impacts on the Iberian Lynx (Lynx pardina Linnaeus) is described. The differences in information content and assessment ability are evaluated. One scale is based on the register of observations along the study corridor of the highway (the "object" approach), and the second on a broad regional landscape ecological analysis assessing the entire Lynx population and the viability for survival of the individual populations that are potentially affected by the highway (the "context" approach). Other data quality and type variations and its influence in the evaluation are also analysed.

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Hervieux, D., M. Hebblewhite, N. J. DeCesare, M. Russell, K. Smith, S. Robertson, and S. Boutin. "Widespread declines in woodland caribou (Rangifer tarandus caribou) continue in Alberta." Canadian Journal of Zoology 91, no. 12 (December 2013): 872–82. http://dx.doi.org/10.1139/cjz-2013-0123.

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Nowhere across Canada is the continued persistence of woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) more uncertain than in Alberta due to widespread industrial development. A recent Government of Canada critical habitat review determined that habitat conditions within all Alberta boreal ecotype caribou ranges are unlikely or very unlikely to allow for self-sustaining caribou populations. This habitat-based assessment was based only indirectly on empirical population trends. Here, we estimated empirical population trend and growth rate (λ) for 13 of Alberta’s 16 remaining woodland caribou populations (plus one adjacent population from Saskatchewan) from 1994 to 2012 using demographic monitoring of adult female survival and calf recruitment. We captured and radio-collared a total of 1337 adult female caribou in 14 populations and estimated the mean annual adult female survival across all populations as 0.851. We conducted 158 late-winter calf recruitment surveys across the 14 populations classifying 20 872 caribou and estimated mean recruitment of 0.154 calves/cow (i.e., 0.077 female calves/cow). We then combined annual estimates of adult female survival and female calf recruitment within each population in a simple age-structured population model to estimate population trend. Annual population growth rate across caribou populations averaged 0.918, and was significantly declining, λ < 1.0, for 10 of the 14 caribou populations. Our results confirm that woodland caribou are declining rapidly (with a realized decline of approximately 50% every 8 years) across Alberta, and support conclusions from previous habitat-based assessments that the population viability of caribou is currently compromised, supporting development and implementation of recovery actions to reverse trends.

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Clark, Tim, Gary Backhouse, and Robert Lacy. "Report of a workshop on population viability assessment as a tool for threatened species management and conservation." Australian Zoologist 27, no. 1-2 (June 1991): 28–35. http://dx.doi.org/10.7882/az.1991.004.

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Carrete, Martina, José A. Sánchez-Zapata, José R. Benítez, Manuel Lobón, and José A. Donázar. "Large scale risk-assessment of wind-farms on population viability of a globally endangered long-lived raptor." Biological Conservation 142, no. 12 (December 2009): 2954–61. http://dx.doi.org/10.1016/j.biocon.2009.07.027.

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McGowan, Conor P., Nathan Allan, Jeff Servoss, Shaula Hedwall, and Brian Wooldridge. "Incorporating population viability models into species status assessment and listing decisions under the U.S. Endangered Species Act." Global Ecology and Conservation 12 (October 2017): 119–30. http://dx.doi.org/10.1016/j.gecco.2017.09.004.

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W. Brook, Barry, Leong Lim, Robert Harden, and Richard Frankham. "How secure is the Lord Howe Island Woodhen? A population viability analysis using VORTEX." Pacific Conservation Biology 3, no. 2 (1997): 125. http://dx.doi.org/10.1071/pc970125.

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The Lord Howe Island Woodhen is a flightless rail endemic to Lord Howe Island that became endangered due to human over-exploitation and predation from wild pigs. It has recently recovered from a population size of 20?30 to around 200 as a result of a captive breeding and reintroduction programme. Its classification has been downgraded from endangered to vulnerable, but no quantitative assessment of its future prospects had been undertaken. A population viability analysis (PVA) was performed on the Lord Howe Island Woodhen to project its possible fate using VORTEX, a package that realistically reflects the woodhen's recent history. Prospective analyses showed the woodhen to be acutely sensitive to minor changes in mortality and fecundity, and to catastrophes, due to exotic species, inbreeding, or disease. A remote population needs to be established if the likelihood of the woodhen's extinction is to be minimized. According to the most recent IUCN Red List categories, the woodhen satisfies the criteria for endangered status.

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Karimov, Aibulat Galim'yanovich. "Deprivation approach towards assessment and analysis of poverty among working population in the region." Социодинамика, no. 6 (June 2020): 57–65. http://dx.doi.org/10.25136/2409-7144.2020.6.33239.

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This article presents some results of studying the problem of poverty among working population from the perspective of deprivation approach. The author analyzes the used approaches towards assessment of poverty, substantiates the viability of deprivation approach and its potential utilization for more comprehensive research of households within the poverty level in the current Russian conditions. The article displays the advantaged of deprivation approach that consists in its linkage to the average living standards in the country, and possibility of assessment of flaws in meeting a wide variety of needs of the households and an individual. A list of deprivations according to which was distinguished the group of population within poverty level is described. The author determines essential differences in assessments of the representatives of “working poor population” distinguished on the grounds of deprivations from other groups of respondents. The conducted analysis allowed revealing the alienation of the group of poor people based on deprivations from the entire population, their essential exclusion from the everyday life of the society. The author underlines that poor people distinguished on the grounds of deprivations are limited not only financially and in sources for overcoming financial difficulties, but the problem of their poverty also worsens by psychological peculiarities of such people – constant deprivations form the “psychology of a poor man”, characterized by insecurities, complacence, and no desire to strive for improvement.  

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Sukhodolov, Alexander, Andrey Fedotov, Mikhail Makarov, Pavel Anoshko, Polina Sorokina, Alina Kolesnikova, and Daria Zhabina. "Prospects of Fish-Husbandry Utilization of Maloye More Fishing Area: Economic Assessment and Substantiation." Bulletin of Baikal State University 30, no. 2 (June 11, 2020): 233–44. http://dx.doi.org/10.17150/2500-2759.2020.30(2).233-244.

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The article was written on the basis of the results of the research conducted by the staff scientists of Limnological Institute of Siberian Branch of the Russian Academy of Sciences and Baikal State University. The aim was to define ecological and economic viability of planting of prospective autochthonous aquatic species including Baikal omul Coregonus migratorius in Maloye More fishing area. The process of fish planting is considered in the light of the need for satisfying the demand for omul both among the local population and tourists visiting Maloye More. The authors give a brief analysis of the demand for fish among the above mentioned categories. On the basis of calculations, a conclusion is drawn that it is impossible to satisfy the need for omul among the population of Maloye More and tourists visiting the area, whose number is growing fast, solely by means of natural propagation. Thus, the authors made an economic assessment of viability of measures aimed at stocking Maloye More fishing area with fish. These measures include acquisition of juvenile omul and its transportation from fish-breeding farms in Irkutsk Region and the Republic of Buryatia and also construction of a fish-breeding farm in Maloye More fishing area.

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McGee, Beth L., Daniel J. Fisher, Lance T. Yonkos, Gregory P. Ziegler, and Steve Turley. "Assessment of sediment contamination, acute toxicity, and population viability of the estuarine amphipodLeptocheirus plumulosusin baltimore harbor, maryland, USA." Environmental Toxicology and Chemistry 18, no. 10 (October 1999): 2151–60. http://dx.doi.org/10.1002/etc.5620181006.

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Jamnia, Abdul Rashid, Ahmad Ali Keikha, Mahmoud Ahmadpour, Abdoul Ahad Cissé, and Mohammad Rokouei. "Applying bayesian population assessment models to artisanal, multispecies fisheries in the Northern Mokran Sea, Iran." Nature Conservation 28 (August 13, 2018): 61–89. http://dx.doi.org/10.3897/natureconservation.28.25212.

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Small-scale fisheries substantially contribute to the reduction of poverty, local economies and food safety in many countries. However, limited and low-quality catches and effort data for small-scale fisheries complicate the stock assessment and management. Bayesian modelling has been advocated when assessing fisheries with limited data. Specifically, Bayesian models can incorporate information of the multiple sources, improve precision in the stock assessments and provide specific levels of uncertainty for estimating the relevant parameters. In this study, therefore, the state-space Bayesian generalised surplus production models will be used in order to estimate the stock status of fourteen Demersal fish species targeted by small-scale fisheries in Sistan and Baluchestan, Iran. The model was estimated using Markov chain Monte Carlo (MCMC) and Gibbs Sampling. Model parameter estimates were evaluated by the formal convergence and stationarity diagnostic tests, indicating convergence and accuracy. They were also aligned with existing parameter estimates for fourteen species of the other locations. This suggests model reliability and demonstrates the utility of Bayesian models. According to estimated fisheries’ management reference points, all assessed fish stocks appear to be overfished. Overfishing considered, the current fisheries management strategies for the small-scale fisheries may need some adjustments to warrant the long-term viability of the fisheries.

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Dean, Susan, Claudio DiBacco, and Robert Scott McKinley. "Assessment of stable isotopic signatures as a means to track the exchange of sea lice (Lepeophtheirus salmonis) between host fish populations." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 7 (July 2011): 1243–51. http://dx.doi.org/10.1139/f2011-039.

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The viability of stable isotopic carbon (δ13C) and nitrogen (δ15N) signatures to track the exchange of sea lice, Lepeophtheirus salmonis , between hosts was tested. It was predicted that nonfeeding sea lice would experience lowered δ13C signatures and enriched δ15N signatures owing, at least in part, to moulting during development. It was also predicted that newly settled parasitic first generation sea lice (late stage copepodids) would retain isotopic signatures indistinguishable from their natal host fish population. During this laboratory study, δ13C signatures of nonfeeding sea lice developmental stages declined over time, while the δ13C signature of chalimus III sea lice was not significantly different from fin and gill signatures of their natal hosts, thus providing an isotopic link to their natal host fish population. In contrast, δ15N analysis did not show promise as a tracer in this study, as host fish populations did not display distinct δ15N signatures. These results suggest that δ13C signatures may be applied to identify sources of sea lice epizootics and potentially quantify the exchange of sea lice between cultured and wild salmon populations.

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Liao, Robert S., Robert P. Rennie, and James A. Talbot. "Assessment of the Effect of Amphotericin B on the Vitality of Candida albicans." Antimicrobial Agents and Chemotherapy 43, no. 5 (May 1, 1999): 1034–41. http://dx.doi.org/10.1128/aac.43.5.1034.

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ABSTRACT The processes involved in cell death are complex, and individual techniques measure specific fractions of the total population. The interaction of Candida albicans with amphotericin B was measured with fluorescent probes with different cellular affinities. These were used to provide qualitative and quantitative information of physiological parameters which contribute to fungal cell viability. SYBR Green I and 5,(6)-carboxyfluorescein were used to assess membrane integrity, and bis-(1,3-dibutylbarbituric acid)trimethine oxonol and 3,3-dihexyloxacarbocyanine iodide were used to evaluate alterations in membrane potential. The fluorescent indicators were compared with replication competency, the conventional indicator of viability. By using these tools, the evaluation of the response of C. albicans to amphotericin B time-kill curves delineated four categories which may represent a continuum between alive and dead. The data showed that replication competency (CFU per milliliter) as determined by conventional antifungal susceptibility techniques provided only an estimate of inhibition. Interpretation of fluorescent staining characteristics indicated that C. albicans cells which were replication incompetent after exposure to greater than 0.5 μg of amphotericin B per ml still maintained degrees of physiological function.

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Ebrahimi, N., N. Viaene, and M. Moens. "Optimizing Trehalose-Based Quantification of Live Eggs in Potato Cyst Nematodes (Globodera rostochiensis and G. pallida)." Plant Disease 99, no. 7 (July 2015): 947–53. http://dx.doi.org/10.1094/pdis-09-14-0940-re.

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Integrated management of potato cyst nematodes (PCN; Globodera rostochiensis and G. pallida) relies heavily on the determination of cyst population densities in soil as well as the viability of the eggs inside the cysts. This study aimed to optimize a quantitative method to determine the number of viable eggs of PCN based on trehalose present in live eggs. Trehalose was extracted from cysts and from a dilution series of eggs and quantified. More trehalose was detected when cysts were crushed than when left intact. Reaction volumes were adapted to the number of eggs because small reaction volumes hampered an accurate extraction of trehalose. A maximum of 10.5 eggs/μl of reaction volume should be used to obtain a significant linear relationship between detected trehalose content and egg numbers. The sensitivity of the trehalose-based method was evaluated by determining the lowest egg detection limit and was defined as five viable eggs. The reliability of this method was tested by comparing efficacy with that of two commonly used assays, visual assessment and hatching test. The trehalose-based method gave viability results similar to those of the visual assessment, which is time consuming, requires trained personnel, and can involve some subjectivity. The hatching test identified fewer viable eggs than the other two methods. In addition, the viability of dead eggs (heated and naturally dead) was tested. No false-positive results (dead eggs declared viable) were obtained with the trehalose-based method. The robustness of the test was demonstrated by measuring the viability of eggs of PCN in different experiments repeated in time. The viability assessment method based on trehalose proved to be an objective as well as sensitive, reliable, robust, fast, and cheap technique for assessing the number of viable eggs in PCN cysts.

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Tuck, G. N., R. A. Phillips, C. Small, R. B. Thomson, N. L. Klaer, F. Taylor, R. M. Wanless, and H. Arrizabalaga. "An assessment of seabird–fishery interactions in the Atlantic Ocean." ICES Journal of Marine Science 68, no. 8 (September 1, 2011): 1628–37. http://dx.doi.org/10.1093/icesjms/fsr118.

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Abstract Tuck, G. N., Phillips, R. A., Small, C., Thomson, R. B., Klaer, N. L., Taylor, F., Wanless, R. M., and Arrizabalaga, H. 2011. An assessment of seabird–fishery interactions in the Atlantic Ocean. – ICES Journal of Marine Science, 68: 1628–1637. Currently, 17 of 22 albatross species are listed as Vulnerable, Endangered, or Critically endangered by the International Union for the Conservation of Nature (IUCN). Incidental mortality in fisheries is by far the most widespread cause of the population declines observed for these and other closely related species. In 2006, the International Commission for the Conservation of Atlantic Tunas (ICCAT) requested an assessment of the threat from their fisheries to all seabirds that breed or forage within their jurisdiction. Methods were developed to assess the potential consequences of fishing for more than 60 populations of seabird. The assessment framework involved the identification of at-risk populations, overlap analyses, estimation of total bycatch, and an evaluation of the impact of the bycatch on key selected populations for which there were sufficient data on bird distribution and demography. These were the wandering and black-browed albatrosses of South Georgia and the Atlantic yellow-nosed and Tristan albatrosses of Gough Island. Summary results from the seabird assessment are presented, revealing that ICCAT longline fisheries catch substantial numbers of seabirds, with potentially significant conservation implications. If this mortality is not reduced, the numbers of breeding birds in some populations will continue to decline, threatening their long-term viability.

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Žalneravičius, Egidijus, and Zigmantas Gudžinskas. "Assessment of the data on distribution, habitats and population size of Liparis loeselii (Orchidaceae) in Lithuania." Botanica Lithuanica 22, no. 1 (June 1, 2016): 3–15. http://dx.doi.org/10.1515/botlit-2016-0001.

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Abstract Liparis loeselii is a declining orchid species in almost all European countries, mostly because of habitat loss. Therefore, good knowledge about the species ecology, distribution and populations is required in order to substantiate measures for its conservation. The aim of this research was to evaluate all available information about distribution, habitat types and population sizes of L. loeselii in Lithuania, in order to reveal the current state of our knowledge and identify information gaps. The study was based on the analysis of herbarium specimens and information in publications and various databases (a total of 481 unique records were used: 118 from herbaria, 121 from literature and 242 from databases). Intensive accumulation of information about L. loeselii started in the second half of the 20th century and a particularly large number of records were made in the period from 2010 to 2015 during the implementation of inventory and mapping of EU Habitats all over Lithuania. A summary of all information about L. loeselii revealed that it was registered in a total of 93 grid squares, and is mainly confined to uplands. The available information is quite sufficient for the evaluation of the species distribution and prevailing habitats, but is incomplete for the evaluation of population sizes, demographic structures and population trends under changing habitat conditions. Additional investigations are, therefore, required to enable a more accurate assessment of the size and viability of the L. loeselii metapopulation in Lithuania.

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Miao, Zongcheng, Yang Zhao, and Xiaoping Huo. "Assessment and determination of lyoprotectant for survival of freeze-dried Lactobacillus rhamnosus." Acta Universitatis Cibiniensis. Series E: Food Technology 20, no. 1 (June 1, 2016): 105–13. http://dx.doi.org/10.1515/aucft-2016-0009.

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Abstract Currently research of lactic acid bacteria focus primarily on the functional probiotics, which are major beneficial biota in the gastrointestinal tract, have been industrial manufactured. Probiotics confer health benefits on the host need adequate amounts. However, the absence of data makes it difficult to ensure the maintenance biological activities and population of probiotic. In this research, a fractional factorial design and steepest ascent experiment were used to analyze the influence of lyoprotectant as carbohydrates, prebiotics and amino acids on the survival of the probiotic Lactobacillus rhamnosus. The results indicated a maximum survival rate and population of viable bacteria of L. rhamnosus to be 55.84 % and 1.60 ×1011 CFU/g after freeze-dried by using a combination of 10 g/100mL Sucrose, 2.5 g/100mL Isomaltooligosaccharide, 12 g/100mL Hydroxyproline. To a large extent, the survival and viability were dependent on the cryoprotectant used and make probiotics more attractive from a practical application in industrial viewpoint.

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Oliveira, Cibele, Thiago Imakawa, and Elaine Moisés. "Physical Activity during Pregnancy: Recommendations and Assessment Tools." Revista Brasileira de Ginecologia e Obstetrícia / RBGO Gynecology and Obstetrics 39, no. 08 (August 2017): 424–32. http://dx.doi.org/10.1055/s-0037-1604180.

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The literature that supports and recommends the practice of exercise during pregnancy is extensive.However, although a more complete research on ways to evaluate the physical activity performed by pregnant women has been perfomed, it is found that there is no gold standard and that the articles in the area are inconclusive. Thus, the objective of the present article is to review relevant aspects, such as, technique and applicability of the different methods for the assessment of physical activity during pregnancy to provide more reliable and safe information for health professionals to encourage their pregnant patients to engage in the practice of physical activity. This review concluded that all tools for the analysis of physical activity have limitations. Thus, it is necessary to establish the objectives of evaluation in an appropriate manner, as well as to determine their viability and cost-effectiveness for the population under study.

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McGee, Beth L., Daniel J. Fisher, Lance T. Yonkos, Gregory P. Ziegler, and Steve Turley. "ASSESSMENT OF SEDIMENT CONTAMINATION, ACUTE TOXICITY, AND POPULATION VIABILITY OF THE ESTUARINE AMPHIPOD LEPTOCHEIRUS PLUMULOSUS IN BALTIMORE HARBOR, MARYLAND, USA." Environmental Toxicology and Chemistry 18, no. 10 (1999): 2151. http://dx.doi.org/10.1897/1551-5028(1999)018<2151:aoscat>2.3.co;2.

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Finkelstein, M. E., D. F. Doak, M. Nakagawa, P. R. Sievert, and J. Klavitter. "Assessment of demographic risk factors and management priorities: impacts on juveniles substantially affect population viability of a long-lived seabird." Animal Conservation 13, no. 2 (April 2010): 148–56. http://dx.doi.org/10.1111/j.1469-1795.2009.00311.x.

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Hoebee, Susan E., Peter H. Thrall, and Andrew G. Young. "Integrating population demography, genetics and self-incompatibility in a viability assessment of the Wee Jasper Grevillea (Grevillea iaspicula McGill., Proteaceae)." Conservation Genetics 9, no. 3 (July 7, 2007): 515–29. http://dx.doi.org/10.1007/s10592-007-9366-3.

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Ruete, Alejandro, Wei Yang, Lars Bärring, Nils Chr Stenseth, and Tord Snäll. "Disentangling effects of uncertainties on population projections: climate change impact on an epixylic bryophyte." Proceedings of the Royal Society B: Biological Sciences 279, no. 1740 (March 28, 2012): 3098–105. http://dx.doi.org/10.1098/rspb.2012.0428.

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Assessment of future ecosystem risks should account for the relevant uncertainty sources. This means accounting for the joint effects of climate variables and using modelling techniques that allow proper treatment of uncertainties. We investigate the influence of three of the IPCC's scenarios of greenhouse gas emissions (special report on emission scenarios (SRES)) on projections of the future abundance of a bryophyte model species. We also compare the relative importance of uncertainty sources on the population projections. The whole chain global climate model (GCM)—regional climate model—population dynamics model is addressed. The uncertainty depends on both natural- and model-related sources, in particular on GCM uncertainty. Ignoring the uncertainties gives an unwarranted impression of confidence in the results. The most likely population development of the bryophyte Buxbaumia viridis towards the end of this century is negative: even with a low-emission scenario, there is more than a 65 per cent risk for the population to be halved. The conclusion of a population decline is valid for all SRES scenarios investigated. Uncertainties are no longer an obstacle, but a mandatory aspect to include in the viability analysis of populations.

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Lonsinger, Robert C., Bryan M. Kluever, Lucas K. Hall, Randy T. Larsen, Eric M. Gese, Lisette P. Waits, and Robert N. Knight. "Conservation of Kit Foxes in the Great Basin Desert: Review and Recommendations." Journal of Fish and Wildlife Management 11, no. 2 (August 31, 2020): 679–98. http://dx.doi.org/10.3996/jfwm-20-025.

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Abstract The kit fox Vulpes macrotis is a species of concern to land managers in the Great Basin Desert of North America. Once common, kit foxes have declined from historical levels. Research on kit foxes in western Utah has spanned nearly 70 y and has potential to inform management and conservation within the Central Basin and Range Ecoregion of the Great Basin Desert. We conducted a systematic literature review on the northern kit fox subspecies V. m. nevadensis. We focused on studies conducted in the Central Basin and Range Ecoregion, which represents the majority of the Great Basin Desert, and provided a comprehensive summary of their ecology and demographics for resource managers. To guide future monitoring, we also reviewed techniques used for kit fox monitoring and research, and evaluated the strengths, limitations, and advances of these techniques. We identified four key factors that deserve consideration when selecting monitoring techniques for kit foxes: estimable parameters, reliability, cost, and rate of data return. Finally, we identify four primary management recommendations. We recommend that managers (1) expand kit fox monitoring and population assessments more broadly across the Great Basin Desert. To ensure future monitoring meets the needs of resource managers, we recommend (2) the application of a structured decision-making process to identify key parameters and approaches. To better understand the factors limiting kit fox populations we recommend (3) population viability and parameter sensitivity analyses to identify drivers of population change. Finally, based on evidence that genetic diversity of kit fox populations has been maintained by undescribed patterns of gene flow, we recommend (4) a broad-scale assessment of population connectivity to identify corridors supporting metapopulation dynamics. These recommendations will facilitate proactive conservation of kit foxes and management practices to reduce future population declines.

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Comley, J. C. W., T. M. Szopa, G. Strote, M. Buttner, K. Darge, and W. Buttner. "A preliminary assessment of the feasibility of evaluating promising antifilarials in vitro against adult Onchocerca volvulus." Parasitology 99, no. 3 (December 1989): 417–25. http://dx.doi.org/10.1017/s003118200005914x.

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SummaryThe suitability of motility indices and tetrazolium-based colorimetric assays for the determination of the viability of adult Onchocerca volvulus after in vitro exposure to potential macrofilaricides has been examined. Experimentation showed that both techniques could be applied to adult O. volvulus, although the variability between individual worms necessitated the use of large experimental groups. The potential of using cut anterior tips of female O. volvulus for screening was also investigated. These were shown to give reasonably consistent motility indices, and drug effects were discernible even after 72 h in vitro culture. Application of these viability criteria to studies on the short-term in vitro survival of intact male and female O. volvulus incubated in Eagles MEM plus serum, under 5% CO2 in air, showed this medium to be suboptimal with a greater than 50 % loss of worm viability within 144 h of nodulectomy. Males isolated by the collagenase technique were shown to be significantly less viable than dissected males, by both motility indices and tetrazolium reduction. The results highlight the need to use either dissected males, or in the case of females, the need to minimize exposure to collagenase solution. A possible mechanism for selecting a more uniformly viable female worm population is discussed. Examination of the in vitro effects of CGP 20376 using these viability criteria/assay systems showed some delayed suppression of worm motility, but after 120 h in vitro CGP 20376 was not macrofilaricidal against male or female O. volvulus. Male worms were also implanted subcutaneously into gerbils. Treatment of these animals with CGP 20376, with autopsy 2 weeks later, resulted in a small macrofilaricidal effect (28% worm death). Some reduction in the motility of living worms recovered from CGP 20376-treated gerbils was also evident. Good survival of control worms recovered 2 weeks post-implantation suggests that male O. volvulus might survive longer subcutaneously. The prospects for undertaking meaningful drug evaluations against O. volvulus in vitro (and in vivo in rodents) is therefore promising, but because of parasite availability will probably be limited to those compounds which have shown potential in other filarial test systems.

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Baqir, S., N. Al-Zeheimi, A. Bani Orabah, A. Al-kindi, Y. Al-Shakaili, and K. Al-Rasbi. "169 QUALITATIVE ASSESSMENT OF ENDANGERED ARABIAN TAHR/IBEX (HEMITRAGUS JAYAKARI) SEMEN USING BIOXCELL® AND TRILADYL® EXTENDERS." Reproduction, Fertility and Development 25, no. 1 (2013): 233. http://dx.doi.org/10.1071/rdv25n1ab169.

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The Arabian tahr/ibex is a small species of goat-antelope-like animal, indigenous to the United Arab Emirates and with a larger population in Oman. Although the animal was discovered in 1894, its numbers continue to decline, and the animal has been classified on the IUCN red list as an endangered species. Little is known about the male reproduction, specifically, extending and cryopreserving semen. This provides a crucial tool for the ex situ conservation of this endangered species. The objective of this study was to evaluate sperm characteristics of the Arabian ibex after dilution in 2 commercial extenders, namely Bioxcell® and Triladyl® based on multiple qualitative parameters. Semen was collected using an electroejaculator from males (n = 4, ~4 years old) during the reproductive season (February–April). Ejaculates were divided into 2 aliquots and extended 1 : 2 in Bioxcell® or Trilidayl® at 37°C. Diluted semen was evaluated for motility with computer-assisted semen analysis (Sperm Vision®, Minitube, Verona, WI, USA). Morphologically, samples were examined with eosin and nigrosin stain under light microscopy, in addition to structural or ultrastructural evaluation with the use of scanning (SEM) or transmission (TEM) electron microscopy. Viability tests were carried out with a LIVE/DEAD® sperm viability kit (Invitrogen, Carlsbad, CA, USA); samples were examined using a fluorescent microscope (Olympus BX51) or with a flow cytometer (FACSAriaTM III, FACSDiva software, BD) with an average flow of 20 000 sperm/event. Sperm samples were liquefied (37°C/5 min), washed with 0.9% NaCl, centrifuged (2000 rpm for 3 min), and filtered using 40-µm nylon mesh (BD, USA) before FACS analysis. Our data showed that semen diluted with Triladyl® had higher motility compared with samples extended with Bioxcell® (60 v. 41%). While eosin and nigrosin staining showed very low morphological abnormalities with both extenders (less than 2%), SEM and TEM assessment demonstrated slightly high incidents of cracked tails, ruptured membrane, and broken midpeace with samples diluted with Bioxcell®. Viability test showed that samples extended with Triladyl® had higher percentages of live sperm (33%) compared with Bioxcell® (21%). Similar viability numbers were obtained with FACSAriaTM III. These results indicate that diluting Arabian ibex semen with Triladyl® would provide improved motility, morphology, and viability compared with Bioxcell®. These findings would be extremely useful for an ex situ conservation program of the Arabian tahr/ibex.

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Blanco, Guillermo, and Francisco Morinha. "Genetic signatures of population bottlenecks, relatedness, and inbreeding highlight recent and novel conservation concerns in the Egyptian vulture." PeerJ 9 (March 25, 2021): e11139. http://dx.doi.org/10.7717/peerj.11139.

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The assessment of temporal variation in genetic features can be particularly informative on the factors behind demography and viability of wildlife populations and species. We used molecular methods to evaluate neutral genetic variation, relatedness, bottlenecks, and inbreeding in a declining population of Egyptian vulture (Neophron percnopterus) in central Spain. The results show that the genetic diversity remained relatively stable over a period of twelve years despite the decline in census and effective population sizes in the last decades. A relatively high proportion of nestlings from different and distant territories showed high relatedness in each study year. We also found support for an increasing impact of severe recent (contemporary) rather than distant (historical) past demographic bottlenecks, and the first evidence of inbred mating between full siblings coinciding with lethal malformations in offspring. The inbred nestling with feather malformations was positive to beak and feather disease virus recorded for the first time in this species. These results alert on recent and novel threats potentially affecting health and reducing the adaptive potential of individuals in this threatened species.

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Coble, Kayla M., Amanda L. Hall, Cody C. Meshes, Joell A. Zalatan, George E. Stanton, and Troy A. Keller. "Replacement of Procambarus acutissimus (Girard) by non-indigenous Procambarus clarkii (Girard) in a disturbed wetland." Freshwater Crayfish 21, no. 1 (December 31, 2015): 153–57. http://dx.doi.org/10.5869/fc.2015.v21-1.153.

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Abstract Of the nearly 600 crayfish species worldwide, more than half are native to North America. The southeastern USA is the epicenter of global crayfish species richness. There is concern about the conservation status of many crayfish species and the viability of their populations. Procambarus acutissimus is a surface dwelling crayfish that is native in Mississippi and Alabama and has isolated populations in west Georgia. Its limited distribution in Georgia prompted this re-assessment of a previously surveyed population in a wetland complex near Columbus, Georgia. To assess the population status of P. acutissimus, we used baited Gee minnow traps to survey crayfish in 2014 following similar protocols used in a 1994 survey. Catches from the littoral zone of a borrow pit lake shifted from only P. acutissimus in 1994 to only Procambarus clarkii, a non-indigenous, invasive species in 2014. Trapping in 2014 documented P. acutissimus in only one of five isolated wetland depressions sampled. Procambarus clarkii appears to be replacing P. acutissimus in this wetland complex. Our results suggest that P. clarkii may displace other crayfish, particularly those that share its affinity for wetland habitats.

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Sommer, S., A. Toto Volahy, and U. S. Seal. "A population and habitat viability assessment for the highly endangered giant jumping rat (Hypogeomys antimena), the largest extant endemic rodent of Madagascar." Animal Conservation 5, no. 4 (November 2002): 263–73. http://dx.doi.org/10.1017/s1367943002004018.

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Рой, Tatyana Roy, Ильичёва, and Elena Ilicheva. "PATTERNS IN LIFE QUALITY CHANGES OF IRKUTSK CITY’S INHABITANTS ACCORDING TO SF-36 QUESTIONNAIRE." Бюллетень Восточно-Сибирского научного центра Сибирского отделения Российской академии медицинских наук 1, no. 4 (November 28, 2016): 119–25. http://dx.doi.org/10.12737/22998.

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Actuality. At the moment, one of the current trends in medicine and sociology is the study of life quality in population. The motivation for this study was the lack of population-based studies on life quality assessment for adult population conducted in Irkutsk, taking into account the individual characteristics of all age groups with questionnaire SF-36.Purpose. To evaluate standard criteria for Irkutsk adult population’s life standard in terms of the age and gender by means of the standard questionnaire SF-36.Materials and methods. The article represents the interview results received from 579 Irkutsk dwellers at the age of 18–85. The Russian version of SF-36 Questionnaire has been used for the present research. The criteria were estimated according to 8scales. The levels of the respondents’ physical well-being, socio-environmental adaptation, psycho-emo-tional changes and viability were specified. Moreover, the respondents’ clinical-anamnestic status including complaints, anamnestic evidences for somatic pathology and earlier surgical interventions were evaluated as well. The received data were processed by Statistica 6.0 software with the use of nonparametric and multiple factor analysis.Results. The results determine the levels of physical functioning, social adaptation, psycho-emotional changes and the viability of Irkutsk residents of different age, gender and socio-professional groups. Conclusions. The presence of comorbidity in varying degrees affected the quality of life

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Christiansen, F., SM Dawson, JW Durban, H. Fearnbach, CA Miller, L. Bejder, M. Uhart, et al. "Population comparison of right whale body condition reveals poor state of the North Atlantic right whale." Marine Ecology Progress Series 640 (April 23, 2020): 1–16. http://dx.doi.org/10.3354/meps13299.

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The North Atlantic right whale Eubalaena glacialis (NARW), currently numbering <410 individuals, is on a trajectory to extinction. Although direct mortality from ship strikes and fishing gear entanglements remain the major threats to the population, reproductive failure, resulting from poor body condition and sublethal chronic entanglement stress, is believed to play a crucial role in the population decline. Using photogrammetry from unmanned aerial vehicles, we conducted the largest population assessment of right whale body condition to date, to determine if the condition of NARWs was poorer than 3 seemingly healthy (i.e. growing) populations of southern right whales E. australis (SRWs) in Argentina, Australia and New Zealand. We found that NARW juveniles, adults and lactating females all had lower body condition scores compared to the SRW populations. While some of the difference could be the result of genetic isolation and adaptations to local environmental conditions, the magnitude suggests that NARWs are in poor condition, which could be suppressing their growth, survival, age of sexual maturation and calving rates. NARW calves were found to be in good condition. Their body length, however, was strongly determined by the body condition of their mothers, suggesting that the poor condition of lactating NARW females may cause a reduction in calf growth rates. This could potentially lead to a reduction in calf survival or an increase in female calving intervals. Hence, the poor body condition of individuals within the NARW population is of major concern for its future viability.

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Braverman, Irus. "Governing the Wild: Databases, Algorithms, and Population Models as Biopolitics." Surveillance & Society 12, no. 1 (March 21, 2014): 15–37. http://dx.doi.org/10.24908/ss.v12i1.4579.

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This essay draws on interviews with conservation biologists to reflect on two interrelated aspects of the in situ – ex situ divide and its increasing integration: database systems and population management models. Specifically, I highlight those databases and software programs used by zoos in ex situ conservation settings, and the parallel, traditionally distinct, in situ databases and risk assessment models. I then explore the evolving technologies that integrate wild-captive databases and population models and, in particular, emerging metapopulation and meta-model approaches to small population management. My central argument is that, while still viewed by many as separate, the in situ and ex situ projects—and their respective elaborate administrative structures and models of calculation—are, in practice, increasingly bleeding into one another. The stories I tell here about the efforts to save the red wolf from extinction reveal the complexities of this integration. I also document how—in this process—a tiny group of experts translates data into algorithmic formats to generate standardized risk calculations that are meant to apply both universally and objectively. Applying Foucauldian and STS insights to the field of conservation biology, I argue, finally, that surveillance and biopolitics work hand-in-hand in this context to enable a comprehensive, effective, and unitary management of nonhuman population life, or “viability”.

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Porter-Armstrong, Alison P., Catherine Adams, Anne S. Moorhead, Jeannie Donnelly, Jane Nixon, Daniel L. Bader, Courtney Lyder, and May D. Stinson. "Do High Frequency Ultrasound Images Support Clinical Skin Assessment?" ISRN Nursing 2013 (February 21, 2013): 1–5. http://dx.doi.org/10.1155/2013/314248.

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High frequency ultrasound imaging has been reported as a potential method of identifying the suspected tissue damage in patients “at risk” of pressure ulceration. The aim of this study was to explore whether ultrasound images supported the clinical skin assessment in an inpatient population through identification of subcutaneous tissue damage. Skin on the heels and/or sacral coccygeal area of fifty vascular surgery inpatients was assessed clinically by tissue viability nurses and with ultrasound pre operatively and at least every other day until discharge. Images were compared to routine clinical skin assessment outcomes. Qualitative classification of ultrasound images did not match outcomes yielded through the clinical skin assessment. Images corresponding to 16 participants were classified as subgroup 3 damage at the heels (equivalent to grade 2 pressure ulceration); clinical skin assessment rated no heels as greater than grade 1a (blanching erythema). Conversely, all images captured of the sacral coccygeal area were classified as normal; the clinical skin assessment rated two participants as grade 1b (non-blanching erythema). Ultrasound imaging is a potentially useful adjunct to the clinical skin assessment in providing information about the underlying tissue. However, further longitudinal clinical assessment is required to characterise images against actual and “staged” pressure ulceration.

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Journal articles on the topic 'Population Viability Assessment'

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