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Olga Renones - One of the best experts on this subject based on the ideXlab platform.
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differential catchability of male and female european spiny lobster palinurus Elephas fabricius 1787 in traps and trammelnets
Fisheries Research, 2003Co-Authors: Raquel Goni, Antoni Quetglas, Olga RenonesAbstract:Abstract A study was carried out to assess the size and sex dependent catchability of Palinurus Elephas in traps by comparing trap catches to trammelnet catches in the Marine Reserve of Columbretes Islands (western Mediterranean) during three different periods. The results indicate that catches of P. Elephas taken with traps do not adequately represent the size structure of the population and that the sex ratios are biased towards females. Trap selectivity primarily affected the estimates of the males’ size structure. The effects on the females’ size structure were limited by their restricted size range. No significant seasonal changes in female catchability in traps relative to nets were noted, but catchability of mature males in traps appeared to be higher before reproduction. Additionally, the catchability of male P. Elephas in traps and trammelnets was highly reduced during moulting. As a result of the above, changes in population structure observed in P. Elephas trap assessment surveys in the reserve appear to be primarily due to seasonal variations in male size structure (operating through trap selectivity) and behaviourally induced changes of male catchability in traps. We discuss the implications of these findings for population assessment. From the point of view of the exploitation and conservation strategy, traps are preferred to trammelnets because they allow for the escape of a certain fraction of immature P. Elephas and they protect the largest males.
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size at maturity fecundity and reproductive potential of a protected population of the spiny lobster palinurus Elephas fabricius 1787 from the western mediterranean
Marine Biology, 2003Co-Authors: Raquel Goni, Antoni Quetglas, Olga RenonesAbstract:Protected lobster populations are expected to contribute to the replenishment of fished populations through increased egg production. We studied the reproductive biology and egg production potential of a population of the spiny lobster Palinurus Elephas protected from fishing since 1990 in the Columbretes Islands Marine Reserve (western Mediterranean). An index of spawning potential was derived to compare egg production potential in the Reserve and in western Mediterranean exploited populations. Females' physiological maturity (ability to reproduce) and functional maturity (ability to mate and bear eggs) occurred at a carapace length (CL) of 76–77 mm. Males' physiological maturity occurred at a slightly larger size, 82.5 mm CL. In the Reserve, P. Elephas' individual fecundity increases linearly with body size up to the females' maximum size, although maximum reproductive yield (eggs per body gram) was reached at intermediate sizes. Size-specific fecundity in the protected population was similar to that of lightly fished populations off Ireland and greater than that of western Mediterranean exploited populations. The female size class of 105–110 mm CL contributed most to egg production in the protected population and is well above the minimum landing size (MLS) for western Mediterranean fisheries. Newly mature females (below MLS) generate a very small fraction (1%) of the egg production from the Reserve. Given the pattern of exploitation in western Mediterranean fisheries, egg production potential depends more on the quantity than on the mean size and fecundity of the available females. The role of the greater availability of large males for mating in unfished populations is discussed in terms of the females' individual fecundity and mating success.
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dynamics of a protected western mediterranean population of the european spiny lobster palinurus Elephas fabricius 1787 assessed by trap surveys
Marine and Freshwater Research, 2001Co-Authors: Raquel Goni, Olga Renones, Antoni QuetglasAbstract:A protected population of the spiny lobster, Palinurus Elephas, was studied eight years after establishment of the Columbretes Islands Marine Reserve (western Mediterranean). Experimental trap fishing in the reserve and at two unprotected sites revealed that cessation of fishing in the reserve is probably responsible for high catch rates observed there and that the annual fishing closure is effective in rebuilding populations in exploited areas. In the reserve, variations in abundance, sex ratio, and size of lobsters were conspicuous. Catch rates were always higher in deep (50–80 m) than in shallow areas (20–50 m). Bathymetric differences in abundance were smallest in early summer, possibly because of seasonal onshore movements associated with reproduction. Females were always more abundant than males and less variable in number and size. Ancillary data suggest that reproductive and moulting behaviour, particularly of males, influences population estimates of P. Elephas from trap surveys. Presence of subadults in deeper waters of the reserve suggests that 2- to 3-year-old juveniles undergo ontogenetic migration from the shallow settlement habitats ( 50 m). The results highlight the effectiveness of fishing restrictions in rebuilding P. Elephas populations and suggest that the lobster population in the reserve is not closed.
Raquel Goni - One of the best experts on this subject based on the ideXlab platform.
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Review of the biology, ecology and fisheries of Palinurus spp. species of European waters: Palinurus Elephas (Fabricius, 1787) and Palinurus mauritanicus (Gruvel, 1911)
Cahiers De Biologie Marine, 2005Co-Authors: Raquel Goni, Daniel LatrouiteAbstract:Palinurus Elephas and Palinurus mauritanicus are the only species of the family Palinuridae that occur in the Northeast Atlantic and Mediterranean. Of the two, Palinurus Elephas is the most abundant and accessible and has traditionally been the preferred target of lobster fisheries throughout its range. Palinurus mauritanicus has a deeper distri- bution and has been an important target of fisheries mainly in the Central Eastern Atlantic. The high unit value and the rel- ative scarcity of these species have been important obstacles to research and knowledge of their biology, ecology and fish- eries is limited. Nevertheless, over time a considerable number of studies has been conducted, though most of these are contained in university theses or in publications of limited circulation. This review is an up-to-date overview of available knowledge on the biology, ecology and fisheries of the two spiny lobster species of European waters.
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differential catchability of male and female european spiny lobster palinurus Elephas fabricius 1787 in traps and trammelnets
Fisheries Research, 2003Co-Authors: Raquel Goni, Antoni Quetglas, Olga RenonesAbstract:Abstract A study was carried out to assess the size and sex dependent catchability of Palinurus Elephas in traps by comparing trap catches to trammelnet catches in the Marine Reserve of Columbretes Islands (western Mediterranean) during three different periods. The results indicate that catches of P. Elephas taken with traps do not adequately represent the size structure of the population and that the sex ratios are biased towards females. Trap selectivity primarily affected the estimates of the males’ size structure. The effects on the females’ size structure were limited by their restricted size range. No significant seasonal changes in female catchability in traps relative to nets were noted, but catchability of mature males in traps appeared to be higher before reproduction. Additionally, the catchability of male P. Elephas in traps and trammelnets was highly reduced during moulting. As a result of the above, changes in population structure observed in P. Elephas trap assessment surveys in the reserve appear to be primarily due to seasonal variations in male size structure (operating through trap selectivity) and behaviourally induced changes of male catchability in traps. We discuss the implications of these findings for population assessment. From the point of view of the exploitation and conservation strategy, traps are preferred to trammelnets because they allow for the escape of a certain fraction of immature P. Elephas and they protect the largest males.
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size at maturity fecundity and reproductive potential of a protected population of the spiny lobster palinurus Elephas fabricius 1787 from the western mediterranean
Marine Biology, 2003Co-Authors: Raquel Goni, Antoni Quetglas, Olga RenonesAbstract:Protected lobster populations are expected to contribute to the replenishment of fished populations through increased egg production. We studied the reproductive biology and egg production potential of a population of the spiny lobster Palinurus Elephas protected from fishing since 1990 in the Columbretes Islands Marine Reserve (western Mediterranean). An index of spawning potential was derived to compare egg production potential in the Reserve and in western Mediterranean exploited populations. Females' physiological maturity (ability to reproduce) and functional maturity (ability to mate and bear eggs) occurred at a carapace length (CL) of 76–77 mm. Males' physiological maturity occurred at a slightly larger size, 82.5 mm CL. In the Reserve, P. Elephas' individual fecundity increases linearly with body size up to the females' maximum size, although maximum reproductive yield (eggs per body gram) was reached at intermediate sizes. Size-specific fecundity in the protected population was similar to that of lightly fished populations off Ireland and greater than that of western Mediterranean exploited populations. The female size class of 105–110 mm CL contributed most to egg production in the protected population and is well above the minimum landing size (MLS) for western Mediterranean fisheries. Newly mature females (below MLS) generate a very small fraction (1%) of the egg production from the Reserve. Given the pattern of exploitation in western Mediterranean fisheries, egg production potential depends more on the quantity than on the mean size and fecundity of the available females. The role of the greater availability of large males for mating in unfished populations is discussed in terms of the females' individual fecundity and mating success.
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dynamics of a protected western mediterranean population of the european spiny lobster palinurus Elephas fabricius 1787 assessed by trap surveys
Marine and Freshwater Research, 2001Co-Authors: Raquel Goni, Olga Renones, Antoni QuetglasAbstract:A protected population of the spiny lobster, Palinurus Elephas, was studied eight years after establishment of the Columbretes Islands Marine Reserve (western Mediterranean). Experimental trap fishing in the reserve and at two unprotected sites revealed that cessation of fishing in the reserve is probably responsible for high catch rates observed there and that the annual fishing closure is effective in rebuilding populations in exploited areas. In the reserve, variations in abundance, sex ratio, and size of lobsters were conspicuous. Catch rates were always higher in deep (50–80 m) than in shallow areas (20–50 m). Bathymetric differences in abundance were smallest in early summer, possibly because of seasonal onshore movements associated with reproduction. Females were always more abundant than males and less variable in number and size. Ancillary data suggest that reproductive and moulting behaviour, particularly of males, influences population estimates of P. Elephas from trap surveys. Presence of subadults in deeper waters of the reserve suggests that 2- to 3-year-old juveniles undergo ontogenetic migration from the shallow settlement habitats ( 50 m). The results highlight the effectiveness of fishing restrictions in rebuilding P. Elephas populations and suggest that the lobster population in the reserve is not closed.
Abdul Jabbar Velayati - One of the best experts on this subject based on the ideXlab platform.
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IDENTIFIKASI CANDIDA SP. PADA RONGGA MULUT GAJAH SUMATERA (Elephas MAXIMUS SUMATRANUS) IDENTIFIKASI CANDIDA SP. PADA RONGGA MULUT GAJAH SUMATERA (Elephas MAXIMUS SUMATRANUS) IDENTIFIKASI CANDIDA SP. PADA RONGGA MULUT GAJAH SUMATERA (Elephas MAXIMUS S
Fakultas Kedokteran Hewan, 2020Co-Authors: Abdul Jabbar VelayatiAbstract:ABSTRAKGajah Sumatera yang dikategorikan sebagai mamalia besar dengan status konservasi critically endangered yang ditetapkan oleh International Union For The Conservation Of Nature And Natural Resources (IUCN). Penelitian ini dilakukan untuk mengidentifikasi Candida sp. Pada rongga mulut gajah Sumatera. Penelitian dilakukan berdasarkan metode Odds dan Bernaerts. Sampel swab rongga mulut gajah diamati setelah ditanam pada media CAC yang diinkubasi selama 48 jam pada suhu 37 ?C. Identifikasi dilakukan berdasarkan pengamatan secara makroskopis terhadap perbedaan warna koloni Candida sp. Hasil pengamatan menunjukkan pada rongga mulut Gajah Sumatera dapat ditumbuhi Candida albicans (100%), Candia tropicalis (100%), Candida parapsilosis (25%), Candida glabrata (25%) dan Candida lainnya (50%). Oleh karena itu dapat disimpulkan bahwa beberapa jenis Candida ditemukan pada rongga mulut gajah Sumatera yaitu: C.albican,C.tropicalis,C.parapsilosis C.glabrata dan C.lainnya.Banda Ace
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IDENTIFIKASI CANDIDA SP. PADA RONGGA MULUT GAJAH SUMATERA (Elephas MAXIMUS SUMATRANUS)
Fakultas Kedokteran Hewan, 2020Co-Authors: Abdul Jabbar VelayatiAbstract:ABSTRAKGajah Sumatera yang dikategorikan sebagai mamalia besar dengan status konservasi critically endangered yang ditetapkan oleh International Union For The Conservation Of Nature And Natural Resources (IUCN). Penelitian ini dilakukan untuk mengidentifikasi Candida sp. Pada rongga mulut gajah Sumatera. Penelitian dilakukan berdasarkan metode Odds dan Bernaerts. Sampel swab rongga mulut gajah diamati setelah ditanam pada media CAC yang diinkubasi selama 48 jam pada suhu 37 ?C. Identifikasi dilakukan berdasarkan pengamatan secara makroskopis terhadap perbedaan warna koloni Candida sp. Hasil pengamatan menunjukkan pada rongga mulut Gajah Sumatera dapat ditumbuhi Candida albicans (100%), Candia tropicalis (100%), Candida parapsilosis (25%), Candida glabrata (25%) dan Candida lainnya (50%). Oleh karena itu dapat disimpulkan bahwa beberapa jenis Candida ditemukan pada rongga mulut gajah Sumatera yaitu: C.a!bidan,C.tropicalis,C.parapsilosis C.glabrata dan C.lainnya.Kata kunci: Candidiasis, Stomatitis, Wildlife, Elephas maximus sumatranusBanda Ace
Marta Pascual - One of the best experts on this subject based on the ideXlab platform.
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effect of oceanographic barriers and overfishing on the population genetic structure of the european spiny lobster palinurus Elephas
Biological Journal of The Linnean Society, 2011Co-Authors: Ferran Palero, Pere Abello, Enrique Macpherson, Mark A Beaumont, Marta PascualAbstract:Defining population structure and genetic diversity levels is of the utmost importance for developing efficient conservation strategies. Overfishing has caused mean annual catches of the European spiny lobster (Palinurus Elephas) to decrease alarmingly along its distribution area. In this context, there is a need for comprehensive studies aiming to evaluate the genetic health of the exploited populations. The present study is based on a set of ten nuclear markers amplified in 331 individuals from ten different localities covering most of P. Elephas distribution area. Samples from Atlantic and Mediterranean basins showed small but significant differences, indicating that P. Elephas populations do not behave as a single panmictic unit but form two partially-overlapping groups. Despite intense overfishing, our dataset did not recover a recent bottleneck signal, and instead showed a large and stable historical effective size. This result could be accounted for by specific life-history traits (reproduction and longevity) and the limitations of molecular markers in covering recent timescales for nontemporal samples. The findings of the present study emphasize the need to integrate information on effective population sizes and life-history parameters when evaluating population connectivity levels from genetic data. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 407–418. ADDITIONAL KEYWORDS: Bayesian – coalescence – DAPC – diversity – long-lived species – microsatellites – phyllosoma – phylogeography.
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phylogeography of the european spiny lobster palinurus Elephas influence of current oceanographical features and historical processes
Molecular Phylogenetics and Evolution, 2008Co-Authors: Ferran Palero, Pere Abello, Enrique Macpherson, Michele Gristina, Marta PascualAbstract:The European spiny lobster (Palinurus Elephas) is a suitable model organism to study the effects of past history and current oceanographic processes on the genetic diversity and population structure of marine species with a long-lived larval phase. A portion of the COI gene was sequenced in 227 individuals from 11 localities, covering most of the present distribution of the species. Divergence was found between Atlantic and Mediterranean regions, which could be explained by restricted gene flow between populations. Moreover, a principal component analysis detected differences within basins. The existence of genetic differentiation between Brittany and Ireland–Scotland populations could be accounted for by the large effect of the Gulf Stream, while mesoscale processes suffered by the incoming Atlantic waters could be responsible of genetic differentiation within the Mediterranean. Furthermore, historical processes could be responsible for a reduction on the overall genetic variability of P. Elephas. The haplotypic distribution found in P. Elephas, with the presence of one abundant haplotype and a large number of closely related haplotypes, is typical of species experiencing reduction in variability and subsequent expansions. Climatic fluctuations related to glacial cycles could explain the present level of variability and nucleotide diversity found. Interestingly, these glacial events do not seem to have the same impact in other species of the same genus. Our results indicate that recent glacial events could have had a lower impact on Palinurus mauritanicus, a congeneric species that presents an overlapping distribution area but is found in cooler waters than P. Elephas.
Ferran Palero - One of the best experts on this subject based on the ideXlab platform.
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effect of oceanographic barriers and overfishing on the population genetic structure of the european spiny lobster palinurus Elephas
Biological Journal of The Linnean Society, 2011Co-Authors: Ferran Palero, Pere Abello, Enrique Macpherson, Mark A Beaumont, Marta PascualAbstract:Defining population structure and genetic diversity levels is of the utmost importance for developing efficient conservation strategies. Overfishing has caused mean annual catches of the European spiny lobster (Palinurus Elephas) to decrease alarmingly along its distribution area. In this context, there is a need for comprehensive studies aiming to evaluate the genetic health of the exploited populations. The present study is based on a set of ten nuclear markers amplified in 331 individuals from ten different localities covering most of P. Elephas distribution area. Samples from Atlantic and Mediterranean basins showed small but significant differences, indicating that P. Elephas populations do not behave as a single panmictic unit but form two partially-overlapping groups. Despite intense overfishing, our dataset did not recover a recent bottleneck signal, and instead showed a large and stable historical effective size. This result could be accounted for by specific life-history traits (reproduction and longevity) and the limitations of molecular markers in covering recent timescales for nontemporal samples. The findings of the present study emphasize the need to integrate information on effective population sizes and life-history parameters when evaluating population connectivity levels from genetic data. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 407–418. ADDITIONAL KEYWORDS: Bayesian – coalescence – DAPC – diversity – long-lived species – microsatellites – phyllosoma – phylogeography.
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phylogeography of the european spiny lobster palinurus Elephas influence of current oceanographical features and historical processes
Molecular Phylogenetics and Evolution, 2008Co-Authors: Ferran Palero, Pere Abello, Enrique Macpherson, Michele Gristina, Marta PascualAbstract:The European spiny lobster (Palinurus Elephas) is a suitable model organism to study the effects of past history and current oceanographic processes on the genetic diversity and population structure of marine species with a long-lived larval phase. A portion of the COI gene was sequenced in 227 individuals from 11 localities, covering most of the present distribution of the species. Divergence was found between Atlantic and Mediterranean regions, which could be explained by restricted gene flow between populations. Moreover, a principal component analysis detected differences within basins. The existence of genetic differentiation between Brittany and Ireland–Scotland populations could be accounted for by the large effect of the Gulf Stream, while mesoscale processes suffered by the incoming Atlantic waters could be responsible of genetic differentiation within the Mediterranean. Furthermore, historical processes could be responsible for a reduction on the overall genetic variability of P. Elephas. The haplotypic distribution found in P. Elephas, with the presence of one abundant haplotype and a large number of closely related haplotypes, is typical of species experiencing reduction in variability and subsequent expansions. Climatic fluctuations related to glacial cycles could explain the present level of variability and nucleotide diversity found. Interestingly, these glacial events do not seem to have the same impact in other species of the same genus. Our results indicate that recent glacial events could have had a lower impact on Palinurus mauritanicus, a congeneric species that presents an overlapping distribution area but is found in cooler waters than P. Elephas.