scholarly journals Population decline and range contraction of the Egyptian Vulture Neophron percnopterus in the Balkan Peninsula

2014 ◽  
Vol 25 (4) ◽  
pp. 440-450 ◽  
Author(s):  
METODIJA VELEVSKI ◽  
STOYAN C. NIKOLOV ◽  
BEN HALLMANN ◽  
VLADIMIR DOBREV ◽  
LAVRENTIS SIDIROPOULOS ◽  
...  
Keyword(s):  
Spatial Scales ◽  
Population Decline ◽  
Balkan Peninsula ◽  
Population Declines ◽  
Egyptian Vulture ◽  
Breeding Grounds ◽  
Conservation Actions ◽  
Causes Of Mortality ◽  
Yugoslav Republic

SummaryThe Egyptian Vulture has been classified as ‘Endangered’ due to a rapid population decline in India and long term declines in Europe and Africa. Although the species has been reported to be declining in Eastern Europe, no quantitative assessment of the magnitude or the causes for population declines are available. We used monitoring data from the Balkan Peninsula to estimate changes in population size and extent of occurrence of Egyptian Vultures between 1980 and 2013. We quantified population trends in three countries (Bulgaria, Greece and the former Yugoslav Republic [FYR] of Macedonia) to assess whether population declines are similar within the Balkan range states. We found a rapid and consistent decline of the Egyptian Vulture population that was largely similar among the three countries (λ = 0.940 in FYR of Macedonia, 0.951 in Bulgaria, 0.920 in Greece). As a consequence of population declines, the breeding range of Egyptian Vultures has contracted and the population in the Balkan Peninsula has fragmented into six subpopulations separated by more than 80 km. Population declines may be driven by factors such as poisoning, electrocution, direct persecution and changes in food availability which operate at large spatial scales and affect birds both on breeding grounds as well as during migration and wintering. Because the relative importance of threats to the survival of Egyptian Vultures are poorly understood, there is a critical need for research into causes of mortality and potential conservation actions that may halt and reverse population declines.

scholarly journals Integrating ecological monitoring and local ecological knowledge to evaluate conservation outcomes

2021 ◽  
Author(s):  
Michelle-María Early-Capistrán ◽  
Elena Solana-Arellano ◽  
F. Alberto Abreu-Grobois ◽  
Gerardo Garibay-Melo ◽  
Jeffrey A. Seminoff ◽  
...  
Keyword(s):  
Gulf Of California ◽  
Local Ecological Knowledge ◽  
Chelonia Mydas ◽  
Ecological Monitoring ◽  
Monitoring Data ◽  
Ecological Knowledge ◽  
Population Declines ◽  
Conservation Actions ◽  
Ecological Science

Successful conservation of long-lived species requires reliable understanding of long-term trends and historical baselines. Using a green turtle (Chelonia mydas) foraging aggregation in the northern Gulf of California, Mexico as case study, we integrated scientific monitoring data with historic catch rate reconstructions derived from Local Ecological Knowledge (LEK). Models fit to LEK and monitoring data indicate that turtle abundance is increasing, but only after ~40 years of safeguarding the species' nesting and foraging habitats in Mexico. However, as population declines occurred 75% faster than increases, and current abundance is at ~60% of historical baseline levels, indicating the need for sustained, long-term conservation actions. This study demonstrates the potential of linking LEK and ecological science to provide critical information for conservation, by establishing reference baselines and gauging population status, while promoting equitable and sustainable futures for local communities.

scholarly journals Site-selection bias can drive apparent population declines in long-term studies

2019 ◽  
Author(s):  
Auriel M.V. Fournier ◽  
Easton R. White ◽  
Stephen B. Heard
Keyword(s):  
Selection Bias ◽  
Site Selection ◽  
Population Decline ◽  
Population Data ◽  
Spatiotemporal Variability ◽  
Population Declines ◽  
Substantial Impact ◽  
Real Population ◽  
Study Sites

Detecting population declines is a critical task for conservation biology. The spatiotemporal variability of populations, along with logistical difficulties in population estimation, makes this task difficult. Here we call attention to a possible bias in estimates of population decline: when study sites are chosen based on abundance of the focal species, for statistical reasons apparent declines are likely even without an underlying population trend. This “site-selection bias” has been mentioned in the literature but is not well known. We show using simulated and real population data that when site-selection biases are introduced, they have substantial impact on inferences about population trends. We use a left-censoring method to show patterns consistent with the operation of the site-selection bias in real population studies. The site-selection bias is, thus, an important consideration for conservation biologists, and we offer suggestions for minimizing or mitigating it in study design and analysis.

scholarly journals Quantifying Threats to Biodiversity and Prioritizing Responses: An Example from Papua New Guinea

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 248
Author(s):  
Thomas H. White ◽  
Patricia Bickley ◽  
Cory Brown ◽  
Dave E. Busch ◽  
Guy Dutson ◽  
...  
Keyword(s):  
Papua New Guinea ◽  
Spatial Scales ◽  
National Level ◽  
New Guinea ◽  
Conservation Actions ◽  
Multivariate Cluster ◽  
Threat Levels ◽  
Specific Conservation ◽  
Do So

Accurately identifying threats to global biodiversity is the first step towards effectively countering or ameliorating them. However, such threats are usually only qualitatively categorized, without any comparative quantitative assessment of threat levels either within or across ecosystems. As part of recent efforts in Papua New Guinea to develop a long-term strategic plan for reducing threats to biodiversity at the national level, we developed a novel and quantitative method for not only assessing relative effects of specific biodiversity threats across multiple ecosystems, but also identifying and prioritizing conservation actions best suited for countering identified threats. To do so, we used an abbreviated quantitative SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis and multivariate cluster analysis to identify the most significant threats to biodiversity in Papua New Guinea. Of 27 specific threats identified, there were nine major threats (each >5% of total) which accounted for approximately 72% of the total quantified biodiversity threat in Papua New Guinea. We then used the information to identify underlying crosscutting threat drivers and specific conservation actions that would have the greatest probability of reducing biodiversity threats across multiple ecosystem realms. We categorized recommended actions within three strategic categories; with actions within each category targeting two different spatial scales. Our integrated quantitative approach to identifying and addressing biodiversity threats is intuitive, comprehensive, repeatable and computationally simple. Analyses of this nature can be invaluable for avoiding not only wasted resources, but also ineffective measures for conserving biodiversity.

scholarly journals Site-selection bias can drive apparent population declines in long-term studies

2019 ◽  
Author(s):  
Auriel M.V. Fournier ◽  
Easton R. White ◽  
Stephen B. Heard
Keyword(s):  
Selection Bias ◽  
Site Selection ◽  
Population Decline ◽  
Population Data ◽  
Spatiotemporal Variability ◽  
Population Declines ◽  
Substantial Impact ◽  
Real Population ◽  
Study Sites

Detecting population declines is a critical task for conservation biology. The spatiotemporal variability of populations, along with logistical difficulties in population estimation, makes this task difficult. Here we call attention to a possible bias in estimates of population decline: when study sites are chosen based on abundance of the focal species, for statistical reasons apparent declines are likely even without an underlying population trend. This “site-selection bias” has been mentioned in the literature but is not well known. We show using simulated and real population data that when site-selection biases are introduced, they have substantial impact on inferences about population trends. We use a left-censoring method to show patterns consistent with the operation of the site-selection bias in real population studies. The site-selection bias is, thus, an important consideration for conservation biologists, and we offer suggestions for minimizing or mitigating it in study design and analysis.

scholarly journals Site-selection bias can drive apparent population declines in long-term studies

2019 ◽  
Author(s):  
Auriel M.V. Fournier ◽  
Easton R. White ◽  
Stephen B. Heard
Keyword(s):  
Selection Bias ◽  
Site Selection ◽  
Population Decline ◽  
Population Data ◽  
Spatiotemporal Variability ◽  
Population Declines ◽  
Substantial Impact ◽  
Real Population ◽  
Study Sites

Detecting population declines is a critical task for conservation biology. The spatiotemporal variability of populations, along with logistical difficulties in population estimation, makes this task difficult. Here we call attention to a possible bias in estimates of population decline: when study sites are chosen based on abundance of the focal species, for statistical reasons apparent declines are likely even without an underlying population trend. This “site-selection bias” has been mentioned in the literature but is not well known. We show using simulated and real population data that when site-selection biases are introduced, they have substantial impact on inferences about population trends. We use a left-censoring method to show patterns consistent with the operation of the site-selection bias in real population studies. The site-selection bias is, thus, an important consideration for conservation biologists, and we offer suggestions for minimizing or mitigating it in study design and analysis.

scholarly journals Site-selection bias can drive apparent population declines in long-term studies

2019 ◽  
Author(s):  
Auriel M.V. Fournier ◽  
Easton R. White ◽  
Stephen B. Heard
Keyword(s):  
Selection Bias ◽  
Site Selection ◽  
Population Decline ◽  
Species Abundance ◽  
Population Data ◽  
Spatiotemporal Variability ◽  
Population Declines ◽  
Substantial Impact ◽  
Real Population

Detecting population declines is a critical task for conservation biology. The spatiotemporal variability of populations, along with logistical difficulties in population estimation, makes this task difficult. Here we call attention to a possible bias in estimates of population decline: when study-site selection is influenced by the focal species’ abundance, for statistical reason declines are likely even without an underlying population trend. This “site-selection bias” has been mentioned in the literature but is not well known. We show using simulated and real population data that when site-selection biases are introduced, they have substantial impact on inferences about population trends. We use a left-censoring method to show patterns consistent with the operation of the site-selection bias in real population studies. The site-selection bias is, thus, an important consideration for conservation biologists, and we offer suggestions for minimizing or mitigating it in study design and analysis.

scholarly journals Responses of Vertebrate Wildlife to Oil and Natural Gas Development: Patterns and Frontiers

2021 ◽  
Author(s):  
A. D. Chalfoun
Keyword(s):  
Natural Gas ◽  
Anthropogenic Activities ◽  
Spatial Scales ◽  
Habitat Type ◽  
Population Level ◽  
Low Frequencies ◽  
Natural Gas Development ◽  
The Usa ◽  
Oil And Natural Gas

Abstract Purpose of Review Anthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’ responses to development and summarize remaining gaps in knowledge. To do so, I evaluated the directionality of a wide variety of responses in relation to taxon, location, development type, development metric, habitat type, and spatiotemporal aspects. Recent Findings Studies (n = 70) were restricted to the USA and Canada, and taxonomically biased towards birds and mammals. Longer studies, but not those incorporating multiple spatial scales, were more likely to detect significant responses. Negative responses of all types were present in relatively low frequencies across all taxa, locations, development types, and development metrics but were context-dependent. The directionality of responses by the same species often varied across studies or development metrics. Summary The state of knowledge about wildlife responses to oil and natural gas development has developed considerably, though many biases and gaps remain. Studies outside of North America and that focus on herpetofauna are lacking. Tests of mechanistic hypotheses for effects, long-term studies, assessment of response thresholds, and experimental designs that isolate the effects of different stimuli associated with development, remain critical. Moreover, tests of the efficacy of habitat mitigation efforts have been rare. Finally, investigations of the demographic effects of development across the full annual cycle were absent for non-game species and are critical for the estimation of population-level effects.

scholarly journals Magnesium and Hypertension in Old Age

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 139 ◽  
Author(s):  
Ligia J. Dominguez ◽  
Nicola Veronese ◽  
Mario Barbagallo
Keyword(s):  
Older Persons ◽  
Magnesium Deficiency ◽  
Favorable Effect ◽  
Processed Food ◽  
Negative Consequences ◽  
Magnesium Supplementation ◽  
Cerebrovascular Complications ◽  
Close Relationship ◽  
Causes Of Mortality

Hypertension is a complex condition in which various actors and mechanisms combine, resulting in cardiovascular and cerebrovascular complications that today represent the most frequent causes of mortality, morbidity, disability, and health expenses worldwide. In the last decades, there has been an exceptional amount of experimental, epidemiological, and clinical studies confirming a close relationship between magnesium deficit and high blood pressure. Multiple mechanisms may help to explain the bulk of evidence supporting a protective effect of magnesium against hypertension and its complications. Hypertension increases sharply with advancing age, hence older persons are those most affected by its negative consequences. They are also more frequently at risk of magnesium deficiency by multiple mechanisms, which may, at least in part, explain the higher frequency of hypertension and its long-term complications. The evidence for a favorable effect of magnesium on hypertension risk emphasizes the importance of broadly encouraging the intake of foods such as vegetables, nuts, whole cereals and legumes, optimal dietary sources of magnesium, avoiding processed food, which are very poor in magnesium and other fundamental nutrients, in order to prevent hypertension. In some cases, when diet is not enough to maintain an adequate magnesium status, magnesium supplementation may be of benefit and has been shown to be well tolerated.

A longitudinal study of humpback whales in Irish waters

2015 ◽  
Vol 96 (4) ◽  
pp. 877-883 ◽  
Author(s):  
Conor Ryan ◽  
Pádraig Whooley ◽  
Simon D. Berrow ◽  
Colin Barnes ◽  
Nick Massett ◽  
...  
Keyword(s):  
Longitudinal Study ◽  
North Atlantic ◽  
Spatial Scales ◽  
Humpback Whales ◽  
Migratory Species ◽  
The Public ◽  
Photo Identification ◽  
The North ◽  
Breeding Grounds ◽  
Eastern North Atlantic

Knowledge on the ecology of humpback whales in the eastern North Atlantic is lacking by comparison with most other ocean basins. Humpback whales were historically over-exploited in the region and are still found in low relative abundances. This, coupled with their large range makes them difficult to study. With the aim of informing more effective conservation measures in Ireland, the Irish Whale and Dolphin Group began recording sightings and images suitable for photo-identification of humpback whales from Irish waters in 1999. Validated records submitted by members of the public and data from dedicated surveys were analysed to form a longitudinal study of individually recognizable humpback whales. The distribution, relative abundance and seasonality of humpback whale sighting records are presented, revealing discrete important areas for humpback whales in Irish coastal waters. An annual easterly movement of humpback whales along the southern coast of Ireland is documented, mirroring that of their preferred prey: herring and sprat. Photo-identification images were compared with others collected throughout the North Atlantic (N = 8016), resulting in matches of two individuals between Ireland and Iceland, Norway and the Netherlands but no matches to known breeding grounds (Cape Verde and West Indies). This study demonstrates that combining public records with dedicated survey data is an effective approach to studying low-density, threatened migratory species over temporal and spatial scales that are relevant to conservation and management.

Protected Areas: offering security to whom, when and where?

2016 ◽  
Vol 43 (2) ◽  
pp. 172-180 ◽  
Author(s):  
ALICE B. KELLY ◽  
A. CLARE GUPTA
Keyword(s):  
Protected Areas ◽  
Environmental Conditions ◽  
Protected Area ◽  
Spatial Scales ◽  
Local Population ◽  
Well Being ◽  
Economic Context ◽  
Term Management ◽  
Over Time

SUMMARYThis study considers the issue of security in the context of protected areas in Cameroon and Botswana. Though the literature on issues of security and well-being in relation to protected areas is extensive, there has been less discussion of how and in what ways these impacts and relationships can change over time, vary with space and differ across spatial scales. Looking at two very different historical trajectories, this study considers the heterogeneity of the security landscapes created by Waza and Chobe protected areas over time and space. This study finds that conservation measures that various subsets of the local population once considered to be ‘bad’ (e.g. violent, exclusionary protected area creation) may be construed as ‘good’ at different historical moments and geographical areas. Similarly, complacency or resignation to the presence of a park can be reversed by changing environmental conditions. Changes in the ways security (material and otherwise) has fluctuated within these two protected areas has implications for the long-term management and funding strategies of newly created and already existing protected areas today. This study suggests that parks must be adaptively managed not only for changing ecological conditions, but also for shifts in a protected area's social, political and economic context.

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