Benigno Elvira | Universidad Complutense de Madrid (original) (raw)
Papers by Benigno Elvira
HAL (Le Centre pour la Communication Scientifique Directe), 2000
International audienceThe symposium was organised by the Department of Animal biology I of Madrid... more International audienceThe symposium was organised by the Department of Animal biology I of Madrid's complutense university and the society to save the sturgeon. More than forty delegates from France, Germany, Greece, Hungary, Poland, Portugal, Romania, Russia, Slovakia, Spain, Ukraine and the USA attented and contributed to the scientific discussions during the sessions. The main objectives of the Symposium were to bring together those concerned with or working on conservation of A. sturio, and to produce a book of proceedings, including an overview of the present knowledge on the subject
Journal of Fish Biology, Jul 1, 2008
Miscel·lània Zoològica, 1986
Fishes
Atlantic salmon Salmo salar supports highly valuable commercial and recreational fisheries in Eur... more Atlantic salmon Salmo salar supports highly valuable commercial and recreational fisheries in Europe, but its stocks are currently overexploited and threatened by climate change. Its southernmost populations (in northern Spain) play a key role in conserving the species’ original genetic diversity, which is endangered due to decades-long (1970s to 1990s) massive stocking with non-native stocks. Their decline is well documented, but the effect of stock transfer and conservation efforts is unclear. Nine microsatellite loci were amplified from archival samples (scales from 1958–1959) from eight Spanish rivers to analyse the species’ natural genetic dynamics before its decline started. Allelic richness was high in the historical populations (the 1950s) and above most contemporary estimates. Private alleles were found in most rivers, indicating high local uniqueness and relative isolation among river basins. Some alleles are regional markers since they are rare or absent from contemporary...
The present conservation status of the endemic flesh-water fish of Spain is reviewed and compared... more The present conservation status of the endemic flesh-water fish of Spain is reviewed and compared with a former list made in 1986. Ten taxa (species and subspecies) are exclusively endemic to Spanish waters, 13 are lberian endemics (Spain and Portugal), while three other species are also found in neighbouring European (France and Italy) or African (Algeria) countries. Endemic species belong to the families Clupeidae (33 % of the native taxa), Cyprinidae (87%), Cobitidae (100%) and Cyprinodontidae (100%). A greater part of the endemic fish fauna is threatened, since three taxa are endangered, five vulnerable, seven rare and two insufficiently known.
Aquatic Sciences
The Southern Iberian spined-loach Cobitis paludica is an Iberian endemism threatened by human act... more The Southern Iberian spined-loach Cobitis paludica is an Iberian endemism threatened by human activities, including habitat destruction. For this reason, the development of conservation and the recovery plans for the species calls for a precise knowledge of its habitat requirements. Here, microhabitat use and selection patterns were investigated to determine the limiting factors for the species in different seasons, corresponding to a gradient in flow conditions. The microhabitat of the loach was analysed in the River Jarama (Tagus River basin, central Spain) in the period of maximum activity between March and September 2013. No significant differences in microhabitat use were found between males and females, and only very weak ontogenetic changes were detected. The microhabitat used by the loach varied significantly throughout the study period, generally adapting to the flow-mediated dynamics of available habitat. The most stable pattern throughout the year was the use of very low ...
Endangered Species Research, 2020
Many Atlantic salmonSalmo salarpopulations in Europe are threatened by previous stocking with for... more Many Atlantic salmonSalmo salarpopulations in Europe are threatened by previous stocking with foreign hatchery strains. Temporal patterns of genetic characteristics of salmon from northern Spain, the southernmost European populations, were compared before and after species decline and heavy stocking with specimens from northern Europe. Eleven microsatellite loci were analysed in archival (scales from 1958-1960) and contemporary (2007-2008) samples from the River Sella. Temporal analyses revealed a similar heterozygosity between archival and contemporary samples, despite a drastic decrease in population abundance, while the contemporary sample showed a higher allelic richness due to the occurrence of foreign alleles. Considering only the alleles with at least 4% frequency in the archival sample, 2 alleles exclusive to the River Sella were absent in the contemporary sample, and 14 alleles showed a decrease of at least 4% frequency. Four alleles common in Scotland showed a high occurre...
ICES Journal of Marine Science, 2019
Historical data on the oceanic distribution and migration routes of southernmost Atlantic salmon ... more Historical data on the oceanic distribution and migration routes of southernmost Atlantic salmon Salmo salar populations from Europe are almost non-existent, as no rigorous tagging initiatives have been conducted. Here, we used stable isotope data (δ13C and δ15N) of historic scale collections to identify the potential marine feeding areas of the largest salmon population in the Iberian Peninsula. Data were compared with published datasets from Northern Ireland, Wales, south England, and northeast UK coast, which correspond to series between 15- and 33-year long within the time period from 1958 to 2009. Temporal covariation in sea surface temperature, primary productivity, and δ13C values suggests that feeding areas of Iberian salmon are located around Greenland, both in the Labrador and the Irminger seas. Furthermore, δ13C values of Atlantic salmon from Canadian rivers reported in the literature are similar to those found in individuals from Spanish rivers. Our results suggest that ...
Science of The Total Environment, 2019
Territorio Henares Cultura Y Naturaleza En Un Espacio Compartido 2011 Isbn 978 84 8138 929 6 Pags 379 403, 2011
El Plan Hidrologico Nacional a Debate 2001 Isbn 84 88949 44 8 Pags 139 146, 2001
Since its first record in a tributary of the Ebro basin in 1992, the bleak Alburnus alburnus has ... more Since its first record in a tributary of the Ebro basin in 1992, the bleak Alburnus alburnus has spread to almost the whole Iberian Peninsula. In this paper (based on elec-trofishing surveys in 598 localities), we provide information on the expansion of the bleak. We detail current distribution in the Ebro basin and the rivers of the Eastern Pyrenees and we report its presence in three other major Iberian drainages. Currently, the bleak is sympatric with 15 Iberian endemic species (58% of total Iberian endemic fish). The possible threats to the rich Iberian ichthyofauna caused by the presence of the bleak are discussed. The factors that promoted the extremely rapid expansion of this exotic cyprinid are examined, focusing on the role of reservoirs, which seem to favour its dis-persal.
River Research and Applications, 2009
River Research and Applications, 2010
Canadian Journal of Fisheries and Aquatic Sciences, 2012
This study looks at the relative influence of water temperature and density dependence on the spa... more This study looks at the relative influence of water temperature and density dependence on the spatial variation in body size of 126 brown trout ( Salmo trutta ) cohorts from 12 Iberian rivers over a 12-year period. Mean cohort mass and length of age groups 0+ to 2+ varied significantly among sampling sites because of the concurrent effect of water temperature and density dependence. Density in suitable habitat had a limiting role that influenced potential maximum growth of cohorts, and water temperature differentiated these cohorts in two groups of sites with high and low potential maximum growth. Water temperature had a positive cumulative effect on body size of all age classes. However, body size of age-0 trout was nonlinearly influenced by short-term exposure to extreme water temperature. Thus, extremely high temperatures became a limiting factor and had deleterious effects on growth. There were intracohort and intercohort effects of density dependence throughout the life span, w...
HAL (Le Centre pour la Communication Scientifique Directe), 2000
International audienceThe symposium was organised by the Department of Animal biology I of Madrid... more International audienceThe symposium was organised by the Department of Animal biology I of Madrid's complutense university and the society to save the sturgeon. More than forty delegates from France, Germany, Greece, Hungary, Poland, Portugal, Romania, Russia, Slovakia, Spain, Ukraine and the USA attented and contributed to the scientific discussions during the sessions. The main objectives of the Symposium were to bring together those concerned with or working on conservation of A. sturio, and to produce a book of proceedings, including an overview of the present knowledge on the subject
Journal of Fish Biology, Jul 1, 2008
Miscel·lània Zoològica, 1986
Fishes
Atlantic salmon Salmo salar supports highly valuable commercial and recreational fisheries in Eur... more Atlantic salmon Salmo salar supports highly valuable commercial and recreational fisheries in Europe, but its stocks are currently overexploited and threatened by climate change. Its southernmost populations (in northern Spain) play a key role in conserving the species’ original genetic diversity, which is endangered due to decades-long (1970s to 1990s) massive stocking with non-native stocks. Their decline is well documented, but the effect of stock transfer and conservation efforts is unclear. Nine microsatellite loci were amplified from archival samples (scales from 1958–1959) from eight Spanish rivers to analyse the species’ natural genetic dynamics before its decline started. Allelic richness was high in the historical populations (the 1950s) and above most contemporary estimates. Private alleles were found in most rivers, indicating high local uniqueness and relative isolation among river basins. Some alleles are regional markers since they are rare or absent from contemporary...
The present conservation status of the endemic flesh-water fish of Spain is reviewed and compared... more The present conservation status of the endemic flesh-water fish of Spain is reviewed and compared with a former list made in 1986. Ten taxa (species and subspecies) are exclusively endemic to Spanish waters, 13 are lberian endemics (Spain and Portugal), while three other species are also found in neighbouring European (France and Italy) or African (Algeria) countries. Endemic species belong to the families Clupeidae (33 % of the native taxa), Cyprinidae (87%), Cobitidae (100%) and Cyprinodontidae (100%). A greater part of the endemic fish fauna is threatened, since three taxa are endangered, five vulnerable, seven rare and two insufficiently known.
Aquatic Sciences
The Southern Iberian spined-loach Cobitis paludica is an Iberian endemism threatened by human act... more The Southern Iberian spined-loach Cobitis paludica is an Iberian endemism threatened by human activities, including habitat destruction. For this reason, the development of conservation and the recovery plans for the species calls for a precise knowledge of its habitat requirements. Here, microhabitat use and selection patterns were investigated to determine the limiting factors for the species in different seasons, corresponding to a gradient in flow conditions. The microhabitat of the loach was analysed in the River Jarama (Tagus River basin, central Spain) in the period of maximum activity between March and September 2013. No significant differences in microhabitat use were found between males and females, and only very weak ontogenetic changes were detected. The microhabitat used by the loach varied significantly throughout the study period, generally adapting to the flow-mediated dynamics of available habitat. The most stable pattern throughout the year was the use of very low ...
Endangered Species Research, 2020
Many Atlantic salmonSalmo salarpopulations in Europe are threatened by previous stocking with for... more Many Atlantic salmonSalmo salarpopulations in Europe are threatened by previous stocking with foreign hatchery strains. Temporal patterns of genetic characteristics of salmon from northern Spain, the southernmost European populations, were compared before and after species decline and heavy stocking with specimens from northern Europe. Eleven microsatellite loci were analysed in archival (scales from 1958-1960) and contemporary (2007-2008) samples from the River Sella. Temporal analyses revealed a similar heterozygosity between archival and contemporary samples, despite a drastic decrease in population abundance, while the contemporary sample showed a higher allelic richness due to the occurrence of foreign alleles. Considering only the alleles with at least 4% frequency in the archival sample, 2 alleles exclusive to the River Sella were absent in the contemporary sample, and 14 alleles showed a decrease of at least 4% frequency. Four alleles common in Scotland showed a high occurre...
ICES Journal of Marine Science, 2019
Historical data on the oceanic distribution and migration routes of southernmost Atlantic salmon ... more Historical data on the oceanic distribution and migration routes of southernmost Atlantic salmon Salmo salar populations from Europe are almost non-existent, as no rigorous tagging initiatives have been conducted. Here, we used stable isotope data (δ13C and δ15N) of historic scale collections to identify the potential marine feeding areas of the largest salmon population in the Iberian Peninsula. Data were compared with published datasets from Northern Ireland, Wales, south England, and northeast UK coast, which correspond to series between 15- and 33-year long within the time period from 1958 to 2009. Temporal covariation in sea surface temperature, primary productivity, and δ13C values suggests that feeding areas of Iberian salmon are located around Greenland, both in the Labrador and the Irminger seas. Furthermore, δ13C values of Atlantic salmon from Canadian rivers reported in the literature are similar to those found in individuals from Spanish rivers. Our results suggest that ...
Science of The Total Environment, 2019
Territorio Henares Cultura Y Naturaleza En Un Espacio Compartido 2011 Isbn 978 84 8138 929 6 Pags 379 403, 2011
El Plan Hidrologico Nacional a Debate 2001 Isbn 84 88949 44 8 Pags 139 146, 2001
Since its first record in a tributary of the Ebro basin in 1992, the bleak Alburnus alburnus has ... more Since its first record in a tributary of the Ebro basin in 1992, the bleak Alburnus alburnus has spread to almost the whole Iberian Peninsula. In this paper (based on elec-trofishing surveys in 598 localities), we provide information on the expansion of the bleak. We detail current distribution in the Ebro basin and the rivers of the Eastern Pyrenees and we report its presence in three other major Iberian drainages. Currently, the bleak is sympatric with 15 Iberian endemic species (58% of total Iberian endemic fish). The possible threats to the rich Iberian ichthyofauna caused by the presence of the bleak are discussed. The factors that promoted the extremely rapid expansion of this exotic cyprinid are examined, focusing on the role of reservoirs, which seem to favour its dis-persal.
River Research and Applications, 2009
River Research and Applications, 2010
Canadian Journal of Fisheries and Aquatic Sciences, 2012
This study looks at the relative influence of water temperature and density dependence on the spa... more This study looks at the relative influence of water temperature and density dependence on the spatial variation in body size of 126 brown trout ( Salmo trutta ) cohorts from 12 Iberian rivers over a 12-year period. Mean cohort mass and length of age groups 0+ to 2+ varied significantly among sampling sites because of the concurrent effect of water temperature and density dependence. Density in suitable habitat had a limiting role that influenced potential maximum growth of cohorts, and water temperature differentiated these cohorts in two groups of sites with high and low potential maximum growth. Water temperature had a positive cumulative effect on body size of all age classes. However, body size of age-0 trout was nonlinearly influenced by short-term exposure to extreme water temperature. Thus, extremely high temperatures became a limiting factor and had deleterious effects on growth. There were intracohort and intercohort effects of density dependence throughout the life span, w...