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Marc Reisch - One of the best experts on this subject based on the ideXlab platform.
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Dupont divests its cellulosic ethanol technology
C&EN Global Enterprise, 2019Co-Authors: Marc ReischAbstract:Dupont has sold its technology for converting cellulosic biomass into ethanol to the Princeton, New Jersey–based chemical process engineering firm Petron Scientech for an undisclosed sum. The deal includes patents and the Zymomonas bacteria strains that Dupont developed for a $200 million–plus ethanol plant in Nevada, Iowa. Dupont closed the plant in 2017, just 2 years after opening it, and sold it last year to Germany’s Verbio, which is revamping the site to make biomethane. Petron say the acquisition will expand its family of renewable fuel and chemical technologies.
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Dupont to end PFAS use
C&EN Global Enterprise, 2019Co-Authors: Marc ReischAbstract:Dupont is pledging to end use of long-chain per- and polyfluoralkyl substances (PFAS) in its manufacturing operations by the end of 2019 and plans to end use of short-chain PFAS “where possible” in the future, a spokesperson says. The firm, which has paid out millions of dollars to settle PFAS water contamination lawsuits, says it is making the commitments to strengthen its position on sustainability and chemical stewardship. Dupont was once a leading manufacturer of PFAS to make products such as Teflon nonstick coatings, but in 2015 it spun off the business into Chemours. PFAS are now associated with diseases including cancer. Dupont also promises to eliminate use of PFAS-containing firefighting foams at its sites by 2021 and to remediate Dupont sites contaminated with PFAS. As part of its stewardship commitment, the firm says it will begin offering royalty-free licenses to its PFAS remediation technology next year. In addition, it
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Dupont says US government made it pollute
C&EN Global Enterprise, 2019Co-Authors: Marc ReischAbstract:In documents filed last month in New Jersey federal district court, Dupont acknowledges it left fluorochemical and explosive contaminants behind at four major New Jersey operations. But the firm claims that it did so as a result of work required by the federal government during World War I and World War II. Dupont’s assertion came to light as the firm attempts to shift suits filed in state courts by New Jersey attorney general Gurbir S. Grewal to federal jurisdiction. The dispute dates back to March, when New Jersey ordered Dupont and Chemours—the Dupont spin-off that owns the contaminated sites—to investigate and clean up poly- and perfluoralkyl substances (PFAS). Scientific studies suggest some PFAS may cause serious health problems. At about the same time, New Jersey filed four lawsuits against Dupont and Chemours in state court seeking clean up at the sites of PFAS contamination as well as contaminants that include
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Dupont to expand tyvek
Chemical & Engineering News, 2018Co-Authors: Marc ReischAbstract:Dupont says it will spend more than $400 million to enlarge capacity for Tyvek polyolefin protective sheeting at its site in Luxembourg. The expansion, which will add a new building and a third operating line at the site, will start up in 2021. Growing global demand is behind the investment in Tyvek, Dupont says. The lightweight, durable material has a variety of uses, including for protective garments, medical packaging, graphics, and as a building moisture-protection wrap. The company celebrated 50 years of Tyvek sales last year, but its development began in 1955 with the discovery of a polyethylene fiber by Dupont researcher Jim White.
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Kevlar jobs not bulletproof at Dupont
C&EN Global Enterprise, 2018Co-Authors: Marc ReischAbstract:Dupont will eliminate about 100 jobs and close a plant in Deepwater, N.J., as part of an effort to lower costs for intermediates used to make the bulletproof aramid fiber Kevlar and its fire-resistant cousin Nomex. Instead, the Indian chemical maker Transpek Industry will supply the intermediates to Dupont’s fiber plant in Richmond, Va. An insider says Dupont chose Transpek to supply the monomers, isophthaloyl chloride and terephthaloyl chloride, because “there are no other suppliers of these materials in the U.S.” The firm adds that Transpek’s technology is newer and more productive than its own. Kevlar is made by reacting p-phenylenediamine and terephthaloyl chloride. Nomex is made by reacting m-phenylenediamine and isophthaloyl chloride. The Deepwater site, known as the Chambers Works, is now owned by Dupont spin-off Chemours. The decision to stop making the intermediates there will allow Dupont to focus on “new products innovations and the modernization” of the
Cristian Perezgranados - One of the best experts on this subject based on the ideXlab platform.
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autonomous recording units as effective tool for monitoring of the rare and patchily distributed Dupont s lark chersophilus Duponti
Ardea, 2018Co-Authors: Cristian Perezgranados, Julia Gomezcatasus, Adrian Barrero, Bustillode D La Rosa, Inmaculada Abrilcolon, Juan TrabaAbstract:Monitoring programmes are needed to assess the conservation status of species and to quantify the effectiveness of conservation effort. Rare species are usually poorly studied due to difficulties in monitoring. We evaluated the use of autonomous recording units (ARUs) coupled with automated song recognition for monitoring the presence of Dupont's Lark Chersophilus Duponti, a rare and patchily distributed species. We surveyed 49 potential habitat patches for the species in central Spain never censused before, from May to June 2017. In each habitat patch we deployed an ARU that recorded one continuous hour during two consecutive nights. In addition, we also performed line transect censuses in 22 out of the 49 potential habitat patches, to evaluate the efficacy of ARUs. Audio analyses revealed the existence of eight previously unrecorded Dupont's Lark populations. Line transect censuses always confirmed the presence or absence of the species in agreement with audio analysis results. ARUs required 44 fewer working days than human-based surveys for monitoring the presence of Dupont's Larks in potential habitat patches. Our results suggest that the use of ARUs coupled with automated song recognition can provide an effective alternative to human-based surveys for monitoring the presence of bird species in large-scale surveys. We conclude that a combined methodology using ARUs and field censuses, in order to estimate densities or spatial patterns, may be considered the most effective method for monitoring large numbers of potential occupancy sites.
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european population trends and current conservation status of an endangered steppe bird species the Dupont s lark chersophilus Duponti
PeerJ, 2018Co-Authors: Julia Gomezcatasus, David Serrano, Cristian Perezgranados, German M Lopeziborra, Adrian Barrero, Gerard Bota, David Giralt, Juan TrabaAbstract:Background Steppe-birds face drastic population declines throughout Europe. The Dupont's lark Chersophilus Duponti is an endangered steppe-bird species whose European distribution is restricted to Spain. This scarce passerine bird could be considered an 'umbrella species', since its population trends may reveal the conservation status of shrub-steppes. However, trends for the Spanish, and thus European, population of Dupont's lark are unknown. In this work, we evaluated Dupont's lark population trends in Europe employing the most recent and largest compiled database to date (92 populations over 12 years). In addition, we assessed the species threat category according to current applicable criteria (approved in March 2017) in the Spanish catalogue of threatened species (SCTS), which have never been applied to the Dupont's lark nor to any other Spanish species. Finally, we compared the resulting threat categories with the current conservation status at European, national and regional levels. Methods We fitted switching linear trend models (software TRIM-Trends and Indices for Monitoring data) to evaluate population trends at national and regional scale (i.e. per Autonomous Community) during the period 2004-2015. In addition, the average finite annual rate of change ( λ ¯ ) obtained from the TRIM analysis was employed to estimate the percentage of population size change in a 10-year period. A threat category was assigned following A1 and A2 criteria applicable in the SCTS. Results Trends showed an overall 3.9% annual decline rate for the Spanish population (moderate decline, following TRIM). Regional analyses showed high inter-regional variability. We forecasted a 32.8% average decline over the next 10 years. According to these results, the species should be listed as 'Vulnerable' at a national scale (SCTS). At the regional level, the conservation status of the species is of particular concern in Andalusia and Castile-Leon, where the species qualifies for listing as 'Endangered'. Discussion Our results highlight the concerning conservation status of the European Dupont's lark population, undergoing a 3.9% annual decline rate. Under this scenario, the implementation of a wide-ranging conservation plan is urgently needed and is vital to ensuring the conservation of this steppe-bird species. The role of administrations in matters of nature protection and the cataloguing of endangered species is crucial to reverse declining population trends of this and other endangered taxa.
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dawn chorus interpretation differs when using songs or calls the Dupont s lark chersophilus Duponti case
PeerJ, 2018Co-Authors: Cristian Perezgranados, Tomasz S Osiejuk, German M LopeziborraAbstract:This research was supported by the project “Estudio aplicado a la conservacion de la conservacion de las poblaciones de alondra ricoti (Chersophilus Duponti) en el entorno del municipio de Vallanca” funded by ‘Levantina y Asociado de Minerales, S.A.”.
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a multi scale analysis of habitat selection in peripheral populations of the endangered Dupont s lark chersophilus Duponti
Bird Conservation International, 2017Co-Authors: Cristian Perezgranados, German M Lopeziborra, Javier SeoaneAbstract:This study was supported by a pre-doctoral fellowship, financed by Levantina y Asociados Minerales, S.A. within the project “Estudios aplicados a la conservacion de las poblaciones de alondra ricoti (Chersophilus Duponti) en el entorno del municipio de Vallanca”.
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breeding biology of the endangered Dupont s lark chersophilus Duponti in two separate spanish shrub steppes
Bird Study, 2017Co-Authors: Cristian Perezgranados, German M Lopeziborra, Vicente Garza, Juan TrabaAbstract:ABSTRACTCapsule: The Dupont’s Lark Chersophilus Duponti in Iberia has relatively high breeding success in both core and fragmented habitats, so population declines are more likely to be the result of low juvenile or adult survival.Aims: To measure important aspects of the reproductive biology of one of the most endangered and least known larks: the Dupont’s Lark C. Duponti.Methods: We monitored 36 nests in 2 Spanish shrub-steppes, one holding one of the largest European populations (250 pairs) and one composed by fragmented habitat patches holding a smaller population (50 pairs).Results: The breeding season went from late-March to early July. Overall mean (±sd) clutch size was 3.47 ± 0.56, and the number of fledglings per successful nest was 3.0 ± 1.15. Mean nestling period was short (8.2 days). Nests showed similar daily survival rate during the incubation period (0.9750 ± 0.0110) as during the nestling period (0.9545 ± 0.0168), with a mean breeding success of 50%. Predation was the main cause of complet...
German M Lopeziborra - One of the best experts on this subject based on the ideXlab platform.
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european population trends and current conservation status of an endangered steppe bird species the Dupont s lark chersophilus Duponti
PeerJ, 2018Co-Authors: Julia Gomezcatasus, David Serrano, Cristian Perezgranados, German M Lopeziborra, Adrian Barrero, Gerard Bota, David Giralt, Juan TrabaAbstract:Background Steppe-birds face drastic population declines throughout Europe. The Dupont's lark Chersophilus Duponti is an endangered steppe-bird species whose European distribution is restricted to Spain. This scarce passerine bird could be considered an 'umbrella species', since its population trends may reveal the conservation status of shrub-steppes. However, trends for the Spanish, and thus European, population of Dupont's lark are unknown. In this work, we evaluated Dupont's lark population trends in Europe employing the most recent and largest compiled database to date (92 populations over 12 years). In addition, we assessed the species threat category according to current applicable criteria (approved in March 2017) in the Spanish catalogue of threatened species (SCTS), which have never been applied to the Dupont's lark nor to any other Spanish species. Finally, we compared the resulting threat categories with the current conservation status at European, national and regional levels. Methods We fitted switching linear trend models (software TRIM-Trends and Indices for Monitoring data) to evaluate population trends at national and regional scale (i.e. per Autonomous Community) during the period 2004-2015. In addition, the average finite annual rate of change ( λ ¯ ) obtained from the TRIM analysis was employed to estimate the percentage of population size change in a 10-year period. A threat category was assigned following A1 and A2 criteria applicable in the SCTS. Results Trends showed an overall 3.9% annual decline rate for the Spanish population (moderate decline, following TRIM). Regional analyses showed high inter-regional variability. We forecasted a 32.8% average decline over the next 10 years. According to these results, the species should be listed as 'Vulnerable' at a national scale (SCTS). At the regional level, the conservation status of the species is of particular concern in Andalusia and Castile-Leon, where the species qualifies for listing as 'Endangered'. Discussion Our results highlight the concerning conservation status of the European Dupont's lark population, undergoing a 3.9% annual decline rate. Under this scenario, the implementation of a wide-ranging conservation plan is urgently needed and is vital to ensuring the conservation of this steppe-bird species. The role of administrations in matters of nature protection and the cataloguing of endangered species is crucial to reverse declining population trends of this and other endangered taxa.
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dawn chorus interpretation differs when using songs or calls the Dupont s lark chersophilus Duponti case
PeerJ, 2018Co-Authors: Cristian Perezgranados, Tomasz S Osiejuk, German M LopeziborraAbstract:This research was supported by the project “Estudio aplicado a la conservacion de la conservacion de las poblaciones de alondra ricoti (Chersophilus Duponti) en el entorno del municipio de Vallanca” funded by ‘Levantina y Asociado de Minerales, S.A.”.
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a multi scale analysis of habitat selection in peripheral populations of the endangered Dupont s lark chersophilus Duponti
Bird Conservation International, 2017Co-Authors: Cristian Perezgranados, German M Lopeziborra, Javier SeoaneAbstract:This study was supported by a pre-doctoral fellowship, financed by Levantina y Asociados Minerales, S.A. within the project “Estudios aplicados a la conservacion de las poblaciones de alondra ricoti (Chersophilus Duponti) en el entorno del municipio de Vallanca”.
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breeding biology of the endangered Dupont s lark chersophilus Duponti in two separate spanish shrub steppes
Bird Study, 2017Co-Authors: Cristian Perezgranados, German M Lopeziborra, Vicente Garza, Juan TrabaAbstract:ABSTRACTCapsule: The Dupont’s Lark Chersophilus Duponti in Iberia has relatively high breeding success in both core and fragmented habitats, so population declines are more likely to be the result of low juvenile or adult survival.Aims: To measure important aspects of the reproductive biology of one of the most endangered and least known larks: the Dupont’s Lark C. Duponti.Methods: We monitored 36 nests in 2 Spanish shrub-steppes, one holding one of the largest European populations (250 pairs) and one composed by fragmented habitat patches holding a smaller population (50 pairs).Results: The breeding season went from late-March to early July. Overall mean (±sd) clutch size was 3.47 ± 0.56, and the number of fledglings per successful nest was 3.0 ± 1.15. Mean nestling period was short (8.2 days). Nests showed similar daily survival rate during the incubation period (0.9750 ± 0.0110) as during the nestling period (0.9545 ± 0.0168), with a mean breeding success of 50%. Predation was the main cause of complet...
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census of breeding birds and population trends of the Dupont s lark chersophilus Duponti in eastern spain
Ardeola, 2013Co-Authors: Cristian Perezgranados, German M LopeziborraAbstract:Summary. We present the results of a breeding census of Dupont's Lark carried out in the Autonomous Community of Valencia in 2011 using the mapping method and an analysis of the recent trend for this population. The population was estimated at 44–47 males, located in five habitat patches of the Rincon de Ademuz, in zones where the species had been detected previously. Density in these patches fits within values expected according to the relation between patch size and density found in the populations of the nearby provinces. Comparison to previous studies reveals that population of Valencia has suffered an annual decline rate of around 10% on average, thus the implementation of a conservation plan is required to ensure the survival of the species in the study area.
Alex Tullo - One of the best experts on this subject based on the ideXlab platform.
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Doyle is out, Breen is in at Dupont
C&EN Global Enterprise, 2020Co-Authors: Alex TulloAbstract:In a major management shake-up, Dupont’s board has ousted CEO Marc Doyle after less than a year on the job. Ed Breen, Dupont’s executive chairman, has been named CEO. Additionally, Chief Financial Officer Jeanmarie Desmond has been replaced by Lori D. Koch, the company’s vice president of investor relations. This isn’t Breen’s first rodeo. He became CEO of Dupont in 2015 when its board fired longtime head Ellen Kullman after a dismal quarter and a contentious fight with the activist investor Nelson Peltz. Once in the job, Breen immediately began negotiating the merger with Dow Chemical to form DowDupont. He led DowDupont from 2017 until last June, when it finished splitting into three firms: Dow, Dupont, and Corteva Agriscience. But Dupont had a rocky start under Doyle. “While we made some progress in 2019, we did not meet our own expectations and we now need to move aggressively to secure
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Chemours sues Dupont
C&EN Global Enterprise, 2019Co-Authors: Alex TulloAbstract:Dupont grossly underestimated the environmental liabilities it saddled Chemours with when it spun off the new company in 2015, according to a Chemours’s lawsuit. The complaint, filed in the Delaware Court of Chancery in May but unsealed on June 28, asks for Dupont to be on the hook for some of the liabilities, or for Dupont to return a nearly $4 billion dividend that Chemours paid Dupont at the spin-off. At the center of the lawsuit are “High End (Maximum) Realistic Exposure” figures—estimates of the liabilities Dupont transferred to Chemours, which took over several Dupont chemical businesses. For example, Dupont had been facing 3,500 lawsuits in Ohio over exposure to perfluorooctanoic acid (PFOA). At spin-off, Dupont determined the maximum liability was $128 million. Dupont later split a $671 million settlement with Chemours. Similarly, Dupont’s Fayetteville, North Carolina, plant, now part of Chemours, had been discharging per- and polyfluoroalkyl substances (PFAS)
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Corteva and Dupont split from DowDupont
C&EN Global Enterprise, 2019Co-Authors: Alex TulloAbstract:The DowDupont era has come to an end. Corteva Agriscience has separated from DowDupont, and the remaining entity is being recast as Dupont. Corteva combines the crop protection chemical and seed businesses of Dow Chemical and Dupont, which merged in 2017 to form DowDupont. The businesses that make up Corteva had sales of $14.3 billion in 2018. Some 56% of these sales came from seeds; the balance was derived from crop protection chemicals. DowDupont shareholders received one share of Corteva for every three shares of DowDupont they owned. It began trading on the New York Stock Exchange on June 3 under the ticker symbol CTVA. “Today marks the launch of a new kind of agriculture company, well positioned to compete and win by providing farmers the complete solution they need for sustainable, long-term growth and improved profitability,” said Corteva CEO Jim Collins, marking the occasion. Dupont has four business segments
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Dupont details unwanted businesses
Chemical & Engineering News, 2019Co-Authors: Alex TulloAbstract:Dupont, which will separate from DowDupont on June 1, has disclosed the 10% of its business portfolio that it no longer wants and is likely to sell. DowDupont officials previously said they wanted to divest 10% of the Dupont portfolio but were scant on details. Dupont will transfer the businesses, which have combined annual sales of about $2 billion, to a new “noncore” operating segment. Included in this group is Dupont’s stake in Hemlock Semiconductor, a silicon joint venture with Corning and Shin-Etsu Handotai. Also in the mix is its biomaterials business, which has a 1,3-propanediol fermentation joint venture with the sugar maker Tate & Lyle. The biomaterials business also makes polytrimethylene terephthalate, a propanediol derivative used in fibers and engineering polymers. Another noncore business is Photovoltaic Solutions and Advanced Materials, which makes metallization pastes and silicone encapsulants. Dupont Clean Technologies, a supplier of technologies for sulfuric acid production and
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Breen fine-tunes R&D at Dupont
C&EN Global Enterprise, 2019Co-Authors: Alex TulloAbstract:R&D will be a key strength of the new Dupont, but projects will need to have strong business cases to survive, Ed Breen, current CEO of DowDupont and future executive chairman of Dupont, told an au...
Juan Traba - One of the best experts on this subject based on the ideXlab platform.
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autonomous recording units as effective tool for monitoring of the rare and patchily distributed Dupont s lark chersophilus Duponti
Ardea, 2018Co-Authors: Cristian Perezgranados, Julia Gomezcatasus, Adrian Barrero, Bustillode D La Rosa, Inmaculada Abrilcolon, Juan TrabaAbstract:Monitoring programmes are needed to assess the conservation status of species and to quantify the effectiveness of conservation effort. Rare species are usually poorly studied due to difficulties in monitoring. We evaluated the use of autonomous recording units (ARUs) coupled with automated song recognition for monitoring the presence of Dupont's Lark Chersophilus Duponti, a rare and patchily distributed species. We surveyed 49 potential habitat patches for the species in central Spain never censused before, from May to June 2017. In each habitat patch we deployed an ARU that recorded one continuous hour during two consecutive nights. In addition, we also performed line transect censuses in 22 out of the 49 potential habitat patches, to evaluate the efficacy of ARUs. Audio analyses revealed the existence of eight previously unrecorded Dupont's Lark populations. Line transect censuses always confirmed the presence or absence of the species in agreement with audio analysis results. ARUs required 44 fewer working days than human-based surveys for monitoring the presence of Dupont's Larks in potential habitat patches. Our results suggest that the use of ARUs coupled with automated song recognition can provide an effective alternative to human-based surveys for monitoring the presence of bird species in large-scale surveys. We conclude that a combined methodology using ARUs and field censuses, in order to estimate densities or spatial patterns, may be considered the most effective method for monitoring large numbers of potential occupancy sites.
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european population trends and current conservation status of an endangered steppe bird species the Dupont s lark chersophilus Duponti
PeerJ, 2018Co-Authors: Julia Gomezcatasus, David Serrano, Cristian Perezgranados, German M Lopeziborra, Adrian Barrero, Gerard Bota, David Giralt, Juan TrabaAbstract:Background Steppe-birds face drastic population declines throughout Europe. The Dupont's lark Chersophilus Duponti is an endangered steppe-bird species whose European distribution is restricted to Spain. This scarce passerine bird could be considered an 'umbrella species', since its population trends may reveal the conservation status of shrub-steppes. However, trends for the Spanish, and thus European, population of Dupont's lark are unknown. In this work, we evaluated Dupont's lark population trends in Europe employing the most recent and largest compiled database to date (92 populations over 12 years). In addition, we assessed the species threat category according to current applicable criteria (approved in March 2017) in the Spanish catalogue of threatened species (SCTS), which have never been applied to the Dupont's lark nor to any other Spanish species. Finally, we compared the resulting threat categories with the current conservation status at European, national and regional levels. Methods We fitted switching linear trend models (software TRIM-Trends and Indices for Monitoring data) to evaluate population trends at national and regional scale (i.e. per Autonomous Community) during the period 2004-2015. In addition, the average finite annual rate of change ( λ ¯ ) obtained from the TRIM analysis was employed to estimate the percentage of population size change in a 10-year period. A threat category was assigned following A1 and A2 criteria applicable in the SCTS. Results Trends showed an overall 3.9% annual decline rate for the Spanish population (moderate decline, following TRIM). Regional analyses showed high inter-regional variability. We forecasted a 32.8% average decline over the next 10 years. According to these results, the species should be listed as 'Vulnerable' at a national scale (SCTS). At the regional level, the conservation status of the species is of particular concern in Andalusia and Castile-Leon, where the species qualifies for listing as 'Endangered'. Discussion Our results highlight the concerning conservation status of the European Dupont's lark population, undergoing a 3.9% annual decline rate. Under this scenario, the implementation of a wide-ranging conservation plan is urgently needed and is vital to ensuring the conservation of this steppe-bird species. The role of administrations in matters of nature protection and the cataloguing of endangered species is crucial to reverse declining population trends of this and other endangered taxa.
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breeding biology of the endangered Dupont s lark chersophilus Duponti in two separate spanish shrub steppes
Bird Study, 2017Co-Authors: Cristian Perezgranados, German M Lopeziborra, Vicente Garza, Juan TrabaAbstract:ABSTRACTCapsule: The Dupont’s Lark Chersophilus Duponti in Iberia has relatively high breeding success in both core and fragmented habitats, so population declines are more likely to be the result of low juvenile or adult survival.Aims: To measure important aspects of the reproductive biology of one of the most endangered and least known larks: the Dupont’s Lark C. Duponti.Methods: We monitored 36 nests in 2 Spanish shrub-steppes, one holding one of the largest European populations (250 pairs) and one composed by fragmented habitat patches holding a smaller population (50 pairs).Results: The breeding season went from late-March to early July. Overall mean (±sd) clutch size was 3.47 ± 0.56, and the number of fledglings per successful nest was 3.0 ± 1.15. Mean nestling period was short (8.2 days). Nests showed similar daily survival rate during the incubation period (0.9750 ± 0.0110) as during the nestling period (0.9545 ± 0.0168), with a mean breeding success of 50%. Predation was the main cause of complet...
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home range territoriality and habitat selection by the Dupont s lark chersophilus Duponti during the breeding and postbreeding periods
2005Co-Authors: Vicente Garza, Juan Traba, Francisco Suarez, Jesus Herranz, Eladio Garcia L De La Morena, Manuel B Morales, Raul Gonzalez, Maria CastanedaAbstract:SUMMARY.—Home range, territoriality and habitat selection by the Dupont’s Lark Chersophilus Duponti during the breeding and postbreeding periods. Aims: Home ranges, habitat use and selection of Dupont’s Lark Chersophilus Duponti during the breeding and postbreeding periods were analysed using radiotagged birds. Location: Layna, central Spain (Soria, 41°05’N, 1°50’W; 1200 m a.s.l.). Methods: A total of 32 birds were radiotagged (22 males, 4 females and 6 juveniles) and monitored nearly daily from April 1st to September 1st. The following variables were measured (1) home ranges using the Minimum Convex Poligon, MCP, (2) core areas using the kernel 80 % density estimator, (3) the distance between successive daily locations, and (4) the degree of overlap of between individuals and periods in home ranges and core areas using Cole’s Index of Concordance. The use and selection of vegetation formations was studied on an individual basis comparing the percentage of bird locations and random points in each vegetation unit. The selection of habitat structure was measured along transects within the birds’ home ranges and compared to that measured along random transects outside home ranges. Results: Home ranges (mean, 8.1 ha), core areas (3.7 ha) and the distance between successive daily locations (around 120 m) did not differ between age-sex classes, or between periods in either sex. Juveniles showed larger core areas and movements than adults during the post-breeding period. Overlap between neighbouring males, as well as between juveniles and adults during the postbreeding period, was scarce in comparison with the overlap between members of the same pair or the overlap between the periods. Two males (9.1%) changed their home ranges during the breeding period, and the only fledgling captured near its nest stayed within paternal home range until at least 1 month old. The density in the study area was 1.0 males/10ha. Dupont’s Lark positively selected Genista pumila shrubs and negatively Genista scorpius shrubs, dry pastures and cereal fields. There were no differences between sexes, nor between periods among adults. Selection by juveniles differed from adult selection during the postbreeding period, using dry pastures more frequently than Genista pumila shrubs. Birds positively selected areas of high pillow-shape shrub cover at ground level, avoiding those of high tall-shrub cover at ground level. A binary logistic regression model including only pillow-shaped shrub cover at ground level as explanatory variable, correctly predicted 76% of home ranges, as confirmed by jacknife re-sampling estimation. Conclusions: Three main conclusions can be drawn from a conservation perspective: (1) the species’ territorial behaviour and strict habitat selection make it highly vulnerable to habitat changes, imposing careful habitat management; (2) management should also regard the marginal habitats used by juveniles; (3) the low density found in one of the best areas for the species in Iberia supports the low estimates of the Spanish population of the Dupont’s Lark made in previous studies.
