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Jorge Landa - One of the best experts on this subject based on the ideXlab platform.
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Age and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland) based on illicia age estimation.
Fisheries Research, 2013Co-Authors: Jorge Landa, Joaquín Barrado, Francisco VelascoAbstract:Abstract The age of white Anglerfish ( Lophius piscatorius ) on the Porcupine Bank was estimated based on the age estimation of 979 illicia (first dorsal fin ray) obtained from a series of 9 annual groundfish surveys (2001–2009). Modifications in the methodology of illicia preparation and in the traditional biased age estimation criterion are presented. This is the first time that a growth pattern of white Anglerfish based on illicia age estimations can be indirectly validated by tracking cohorts using the abundance indices per age class from surveys and length-frequency analyses. Previous studies of cohort tracking using the traditional illicia age estimation criterion showed a mismatch, suggesting a faster growth. With the new proposed criteria, abundant cohorts from 2001 to 2004, and scarce ones, from 2005 to 2007, can be tracked over the time throughout several age groups. A new growth pattern and von Bertalanffy growth parameters are presented ( L ∞ : 162.31; k : 0.088; t 0 : −0.894). The results are compared with previous studies in other areas.
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Distribution, abundance, and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland)
ICES Journal of Marine Science, 2008Co-Authors: Francisco Velasco, Jorge Landa, Joaquín Barrado, M. BlancoAbstract:Velasco, F., Landa, J., Barrado, J., and Blanco, M. 2008. Distribution, abundance, and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland). - ICES Journal of Marine Science, 65: 1316-1325.This manuscript presents the first results on abundance and distribution of white Anglerfish (Lophius piscatorius) from a series of groundfish surveys carried out on the Porcupine Bank. White Anglerfish were caught in all trawlable areas, recruits and juveniles mainly from the shallower parts of the bank, around the central mound and closer to the Irish shelf. A strong cohort was manifest in 2001, and it could be tracked over time by age matrices obtained with illicia age-length keys (ALKs) collected during the surveys. However, a mismatch in the cohort analysis suggests that the growth pattern based on illicia underestimates around three of the younger age classes. Using an ALK estimated numerically from a faster growth model, this mismatch disappears, which seems to confirm faster growth. Recruits of the 0-group and adults of age 4 (with the faster growth: ca. ∼57-65 cm) dominated, whereas the intermediate age groups were scarce on the bank. These results and recent findings from tag-and-recapture experiments suggest that white Anglerfish move to and from the Porcupine Bank, calling into question the stock boundaries currently accepted for the species in the North Atlantic.
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Application of dynamic factor analysis in the assessment of Iberian Anglerfish stocks
ICES Journal of Marine Science, 2008Co-Authors: Manuela Azevedo, Jorge Landa, Rafael Duarte, Fátima Cardador, Pedro Sousa, Celso Fariña, Paz Sampedro, Gersom CostasAbstract:Azevedo, M., Duarte, R., Cardador, F., Sousa, P., Farina, C., Sampedro, P., Landa, J., and Costas, G. 2008. Application of dynamic factor analysis in the assessment of Iberian Anglerfish stocks. - ICES Journal of Marine Science, 65: 1362-1369.Dynamic factor analysis (DFA) was applied to six time-series of catch per unit effort data of the Iberian (ICES Divisions VIIIc and IXa) white Anglerfish (Lophius piscatorius) and black Anglerfish (L. budegassa). Results showed that grouping the abundance indices reflected the fleet's area of exploitation and fish size selection. Two common trends (CTs) were extracted for each species, capturing the main signal of abundance over time. The white Anglerfish was assessed using these CTs as input to the biomass dynamic model currently used in the ICES assessment, to investigate whether the approach would reduce the uncertainty in parameter estimates and related quantities. Using the CTs, bias estimates are lower. The current perception of an overexploited stock is unchanged, but a much lower intrinsic rate of biomass increase was estimated, indicating that the biomass recovery might be much slower. A lower maximum sustainable yield, ∼3600 t, was obtained, and this is more consistent with the historical landings trajectory. The application of DFA to stock assessment of Anglerfish, presented here for the first time, can be extended to age-based assessments.
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Movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in the northeast Atlantic
Fisheries Research, 2008Co-Authors: Jorge Landa, Rafael Duarte, Iñaki Quincoces, A.c. Fariña, Herve DupouyAbstract:Abstract Within the frame of an international tagging program which has been carried out since 1995, movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in Southern European waters were studied. This is the first large-scale study on movements of tagged black Anglerfish. A total of 877 black Anglerfish (6–88 cm total length) and 1326 white Anglerfish (15–137 cm total length) were tagged. Times at liberty ranged from 1 to 665 days, with recapture rates of 21 (2.4%) and 50 (3.8%), respectively. A description of our tagging procedures is presented, together with the influences of the gear used, fish length and area of tagging on recapture rates. The type of fishing gear was the main factor affecting recapture rates. Fish length was neither related to the displacement distance nor to the time at liberty while the displacement distance was related to the time at liberty. Recapture locations suggested that movements occurred both in- and offshore. The largest displacement recorded was 408 km of a black Anglerfish from southern to northern Bay of Biscay. The movements of the Anglerfish indicate a mixing between northern and southern populations which may have strong implications for the current geographical boundaries of the stocks from a management perspective. Here, movement of white Anglerfish between the Le Danois Bank and the Cantabrian continental shelf is reported for the first time.
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Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish
ICES Journal of Marine Science, 2007Co-Authors: Jorge Landa, Rafael Duarte, Iñaki QuincocesAbstract:Landa, J., Duarte, R., and Quincoces, I. 2008. Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish. - ICES Journal of Marine Science, 65: 72-80.Growth of white Anglerfish was estimated from the results of a tagging study in south European waters. In all, 1326 fish, caught by bottom trawl and gillnet commercial vessels and on trawl surveys, were tagged from 1995 to 2004; 50 were recovered, and a growth rate of 13.6 cm year −1 was estimated from the four fish at liberty long enough to allow extrapolation of the growth rate to an annual period. Growth patterns were reviewed based on available studies of growth verification of white Anglerfish in Atlantic waters, including another tag-recapture study, length-frequency of catches, and microstructure analysis of hard parts. The growth rate estimated from these studies showed many similarities, and an overall growth pattern was estimated: growth rate = 18.24e -0.015length . A von Bertalanffy growth curve fitted to all data yielded the parameter values L ∞ = 140 cm and k = 0.11. This growth rate is faster than estimated recently using illicia for age estimation, but similar to that found in the first studies that used illicia and sectioned otoliths. Current estimates of growth based on illicia, which are used in assessing the northern European stock of white Anglerfish, seem to be underestimated.
Joachim Spiess - One of the best experts on this subject based on the ideXlab platform.
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Processing of an Anglerfish somatostatin precursor to a hydroxylysine-containing somatostatin 28 (pancreatic islets/hydroxylation/thermolysin/automatic Edman degradation/reversed-phase high-pressure liquid chromatography)
2016Co-Authors: Joachim Spiess, Bryan D NoettAbstract:A novel 28-residue somatostatin (SS) has been isolated from Anglerfish pancreatic islets and character- ized by complete Edman degradation, peptide mapping, and amino acid analysis. The primary structihre of this Anglerfish SS-28 (aSS-28) containing hydroxylysine (Hyl) was established to be H-Ser-Val-Asp-Ser-Thr-Asn-Asn-Leu-Pro-Pro-Arg-Glu- Arg-Lys-Ala-Gly-Cys-Lys-Asn-Phe-Tyr-Trp-Hyl-Gly- Phe-Thr-Ser-Cys-OH. This sequence (with the exception of hy- droxylysine-23, which is replaced by lysine) is identical to the sequence of the COOH-terminal 28 residues of prepro-SS II predicted on the basis of cDNA analysis (Hobart, P., Craw- ford, R., Shen, L., Pictet, R. & Rutter, W. J. (1980) Nature (Londont) 288, 137-141). This is the first instance in which hydroxylysine (to date characteristically observed in collagen or collagen-like structures) has been found in a potential regu- latory peptide. Chromatographic characterization of peptides, radiolabeled in islet culture, revealed that aSS-28 contained 10-12% of the radioactivity incorporated into the 8000- to 1000-dalton SS-like polypeptides, whereas 88-90% of this ra- dioactivity was detected in Anglerfish SS-14. It appears proba- ble that aSS-28. represents the predominant primary cleavage product derived from prepro-SS II by cleavage at the COOH- terminal side of a single arginine. Based on knowledge of the collagen biosynthesis, it is speculated that hydroxylation may take place as an early post-translational event.
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processing of an Anglerfish somatostatin precursor to a hydroxylysine containing somatostatin 28 pancreatic islets hydroxylation thermolysin automatic edman degradation reversed phase high pressure liquid chromatography
2016Co-Authors: Joachim Spiess, Bryan D NoettAbstract:A novel 28-residue somatostatin (SS) has been isolated from Anglerfish pancreatic islets and character- ized by complete Edman degradation, peptide mapping, and amino acid analysis. The primary structihre of this Anglerfish SS-28 (aSS-28) containing hydroxylysine (Hyl) was established to be H-Ser-Val-Asp-Ser-Thr-Asn-Asn-Leu-Pro-Pro-Arg-Glu- Arg-Lys-Ala-Gly-Cys-Lys-Asn-Phe-Tyr-Trp-Hyl-Gly- Phe-Thr-Ser-Cys-OH. This sequence (with the exception of hy- droxylysine-23, which is replaced by lysine) is identical to the sequence of the COOH-terminal 28 residues of prepro-SS II predicted on the basis of cDNA analysis (Hobart, P., Craw- ford, R., Shen, L., Pictet, R. & Rutter, W. J. (1980) Nature (Londont) 288, 137-141). This is the first instance in which hydroxylysine (to date characteristically observed in collagen or collagen-like structures) has been found in a potential regu- latory peptide. Chromatographic characterization of peptides, radiolabeled in islet culture, revealed that aSS-28 contained 10-12% of the radioactivity incorporated into the 8000- to 1000-dalton SS-like polypeptides, whereas 88-90% of this ra- dioactivity was detected in Anglerfish SS-14. It appears proba- ble that aSS-28. represents the predominant primary cleavage product derived from prepro-SS II by cleavage at the COOH- terminal side of a single arginine. Based on knowledge of the collagen biosynthesis, it is speculated that hydroxylation may take place as an early post-translational event.
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Comparison of Prohormone-process ing Activities in Islet Microsomes and Secretory Granules: Evidence for Distinct Converting Enzymes for Separate Islet Prosomatostatins
2013Co-Authors: Bryan D. Noe, Gail Debo, Joachim SpiessAbstract:ABSTRACT In previous work we have examined the nature of converting enzymes for proinsulin, proglucagon, and prosomatostatin-I (PSS-I) in Secretory granules isolated from Anglerfish islets. The purpose of the present study was to extend the examination of precursor conversion to islet microsomes and to compare prohormone processing, including that of PSS-I and prosomatostatin-II (PSS-II), in islet Secretory granules and microsomes. Microsomes (rough endoplasmic reticulum [RER] and Golgi complex) and Secretory granules were prepared from Anglerfish islets by differential and discontinuous density-gradient centrifugation. Microsomes were further fractionated into Golgi- and RER-enriched subtractions. Lysed Secretory granule or microsome preparations were incubated in the presence of a mixture of radioactively labeled islet prohormones. Extracts of products generated were subjected to analysis by gel filtration and high-pressure liquid chromatography. Accuracy of product cleavage was monitored by comparing high-pressure liquid chromatography retention times from the radiolabeled in vitro conversion products with the retention times of labeled products from tissue extracts. All converting activity in microsomes was found to be similar to that in granules in that i
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The Anglerfish somatostatin-28-generating propeptide converting enzyme is an aspartyl protease
Endocrinology, 1991Co-Authors: Robert B. Mackin, Bryan D. Noe, Joachim SpiessAbstract:An enzyme that performs the conversion of Anglerfish prosomatostatin-H (pro-SS-II) to Anglerfish SS-28 has been identified using an improved two-dimensional electrophoresis procedure. The enzyme is a single chain 39 kDa polypeptide with its isoelectric point at pH 5.9. The converting enzyme has an acidic pH optimum, consistent with the lowered pH of the intracellular site of propeptide conversion. Secretory granule extracts were examined to determine the inhibitor sensitivity and pH optimum of the conversion of Anglerfish pro-SSII to Anglerfish SS-28 in this organelle. Production of Anglerfish SS-28 by secretory granules was maximal at pH 4.2 and was completely inhibited by the addition of pepstatin. Since pepstatin is a specific inhibitor of aspartyl proteases, these results indicate that the purified enzyme is a member of this enzyme family. This conclusion was supported by the data from partial amino acid sequence analysis. Because these results are consistent with the role of the purified enzyme in th...
Rafael Duarte - One of the best experts on this subject based on the ideXlab platform.
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Application of dynamic factor analysis in the assessment of Iberian Anglerfish stocks
2016Co-Authors: Manuela Azevedo, Rafael Duarte, Pedro Sousa, Paz Sampedro, Jorge L, Gersom CostasAbstract:Dynamic factor analysis (DFA) was applied to six time-series of catch per unit effort data of the Iberian (ICES Divisions VIIIc and IXa) white Anglerfish (Lophius piscatorius) and black Anglerfish (L. budegassa). Results showed that grouping the abundance indices reflected the fleet’s area of exploitation and fish size selection. Two common trends (CTs) were extracted for each species, capturing the main signal of abundance over time. The white Anglerfish was assessed using these CTs as input to the biomass dynamic model currently used in the ICES assessment, to investigate whether the approach would reduce the uncertainty in parameter estimates and related quantities. Using the CTs, bias estimates are lower. The current perception of an overexploited stock is unchanged, but a much lower intrinsic rate of biomass increase was estimated, indicating that the biomass recovery might be much slower. A lower maximum sustainable yield, 3600 t, was obtained, and this is more consistent with the historical landings trajectory. The application of DFA to stock assessment of Anglerfish, presented here for the first time, can be extended to age-based assessments
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Monkfish/Anglerfish across the world; common problems and common solutions: an introduction to papers presented at the ICES Theme Session in September 2007
ICES Journal of Marine Science, 2008Co-Authors: Jean-jacques Maguire, Rafael Duarte, Pilar Pereda, Helen Dobby, Manuela AzevedoAbstract:Maguire, J-J., Pereda, P., Duarte R., Dobby, H., and Azevedo, M. 2008. Monkfish/Anglerfish across the world; common problems and common solutions: An introduction to papers presented at the ICES Theme Session in September 2007. - ICES Journal of Marine Science, 65: 1270-1271.
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Application of dynamic factor analysis in the assessment of Iberian Anglerfish stocks
ICES Journal of Marine Science, 2008Co-Authors: Manuela Azevedo, Jorge Landa, Rafael Duarte, Fátima Cardador, Pedro Sousa, Celso Fariña, Paz Sampedro, Gersom CostasAbstract:Azevedo, M., Duarte, R., Cardador, F., Sousa, P., Farina, C., Sampedro, P., Landa, J., and Costas, G. 2008. Application of dynamic factor analysis in the assessment of Iberian Anglerfish stocks. - ICES Journal of Marine Science, 65: 1362-1369.Dynamic factor analysis (DFA) was applied to six time-series of catch per unit effort data of the Iberian (ICES Divisions VIIIc and IXa) white Anglerfish (Lophius piscatorius) and black Anglerfish (L. budegassa). Results showed that grouping the abundance indices reflected the fleet's area of exploitation and fish size selection. Two common trends (CTs) were extracted for each species, capturing the main signal of abundance over time. The white Anglerfish was assessed using these CTs as input to the biomass dynamic model currently used in the ICES assessment, to investigate whether the approach would reduce the uncertainty in parameter estimates and related quantities. Using the CTs, bias estimates are lower. The current perception of an overexploited stock is unchanged, but a much lower intrinsic rate of biomass increase was estimated, indicating that the biomass recovery might be much slower. A lower maximum sustainable yield, ∼3600 t, was obtained, and this is more consistent with the historical landings trajectory. The application of DFA to stock assessment of Anglerfish, presented here for the first time, can be extended to age-based assessments.
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Movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in the northeast Atlantic
Fisheries Research, 2008Co-Authors: Jorge Landa, Rafael Duarte, Iñaki Quincoces, A.c. Fariña, Herve DupouyAbstract:Abstract Within the frame of an international tagging program which has been carried out since 1995, movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in Southern European waters were studied. This is the first large-scale study on movements of tagged black Anglerfish. A total of 877 black Anglerfish (6–88 cm total length) and 1326 white Anglerfish (15–137 cm total length) were tagged. Times at liberty ranged from 1 to 665 days, with recapture rates of 21 (2.4%) and 50 (3.8%), respectively. A description of our tagging procedures is presented, together with the influences of the gear used, fish length and area of tagging on recapture rates. The type of fishing gear was the main factor affecting recapture rates. Fish length was neither related to the displacement distance nor to the time at liberty while the displacement distance was related to the time at liberty. Recapture locations suggested that movements occurred both in- and offshore. The largest displacement recorded was 408 km of a black Anglerfish from southern to northern Bay of Biscay. The movements of the Anglerfish indicate a mixing between northern and southern populations which may have strong implications for the current geographical boundaries of the stocks from a management perspective. Here, movement of white Anglerfish between the Le Danois Bank and the Cantabrian continental shelf is reported for the first time.
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Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish
ICES Journal of Marine Science, 2007Co-Authors: Jorge Landa, Rafael Duarte, Iñaki QuincocesAbstract:Landa, J., Duarte, R., and Quincoces, I. 2008. Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish. - ICES Journal of Marine Science, 65: 72-80.Growth of white Anglerfish was estimated from the results of a tagging study in south European waters. In all, 1326 fish, caught by bottom trawl and gillnet commercial vessels and on trawl surveys, were tagged from 1995 to 2004; 50 were recovered, and a growth rate of 13.6 cm year −1 was estimated from the four fish at liberty long enough to allow extrapolation of the growth rate to an annual period. Growth patterns were reviewed based on available studies of growth verification of white Anglerfish in Atlantic waters, including another tag-recapture study, length-frequency of catches, and microstructure analysis of hard parts. The growth rate estimated from these studies showed many similarities, and an overall growth pattern was estimated: growth rate = 18.24e -0.015length . A von Bertalanffy growth curve fitted to all data yielded the parameter values L ∞ = 140 cm and k = 0.11. This growth rate is faster than estimated recently using illicia for age estimation, but similar to that found in the first studies that used illicia and sectioned otoliths. Current estimates of growth based on illicia, which are used in assessing the northern European stock of white Anglerfish, seem to be underestimated.
Francisco Velasco - One of the best experts on this subject based on the ideXlab platform.
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Distribution, abundance, and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland)
2014Co-Authors: Francisco Velasco, Jorge L, M. BlancoAbstract:This manuscript presents the first results on abundance and distribution of white Anglerfish (Lophius piscatorius) from a series of groundfish surveys carried out on the Porcupine Bank. White Anglerfish were caught in all trawlable areas, recruits and juveniles mainly from the shallower parts of the bank, around the central mound and closer to the Irish shelf. A strong cohort was manifest in 2001, and it could be tracked over time by age matrices obtained with illicia age–length keys (ALKs) collected during the surveys. However, a mismatch in the cohort analysis suggests that the growth pattern based on illicia underestimates around three of the younger age classes. Using an ALK estimated numerically from a faster growth model, this mismatch disappears, which seems to confirm faster growth. Recruits of the 0-group and adults of age 4 (with the faster growth: ca. 57–65 cm) dominated, whereas the intermediate age groups were scarce on the bank. These results and recent findings from tag-and-recapture experiments suggest that white Anglerfish move to and from the Porcupine Bank, calling into question the stock boundaries currently accepted for the species in the North Atlantic
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Age and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland) based on illicia age estimation.
Fisheries Research, 2013Co-Authors: Jorge Landa, Joaquín Barrado, Francisco VelascoAbstract:Abstract The age of white Anglerfish ( Lophius piscatorius ) on the Porcupine Bank was estimated based on the age estimation of 979 illicia (first dorsal fin ray) obtained from a series of 9 annual groundfish surveys (2001–2009). Modifications in the methodology of illicia preparation and in the traditional biased age estimation criterion are presented. This is the first time that a growth pattern of white Anglerfish based on illicia age estimations can be indirectly validated by tracking cohorts using the abundance indices per age class from surveys and length-frequency analyses. Previous studies of cohort tracking using the traditional illicia age estimation criterion showed a mismatch, suggesting a faster growth. With the new proposed criteria, abundant cohorts from 2001 to 2004, and scarce ones, from 2005 to 2007, can be tracked over the time throughout several age groups. A new growth pattern and von Bertalanffy growth parameters are presented ( L ∞ : 162.31; k : 0.088; t 0 : −0.894). The results are compared with previous studies in other areas.
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Distribution, abundance, and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland)
ICES Journal of Marine Science, 2008Co-Authors: Francisco Velasco, Jorge Landa, Joaquín Barrado, M. BlancoAbstract:Velasco, F., Landa, J., Barrado, J., and Blanco, M. 2008. Distribution, abundance, and growth of Anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland). - ICES Journal of Marine Science, 65: 1316-1325.This manuscript presents the first results on abundance and distribution of white Anglerfish (Lophius piscatorius) from a series of groundfish surveys carried out on the Porcupine Bank. White Anglerfish were caught in all trawlable areas, recruits and juveniles mainly from the shallower parts of the bank, around the central mound and closer to the Irish shelf. A strong cohort was manifest in 2001, and it could be tracked over time by age matrices obtained with illicia age-length keys (ALKs) collected during the surveys. However, a mismatch in the cohort analysis suggests that the growth pattern based on illicia underestimates around three of the younger age classes. Using an ALK estimated numerically from a faster growth model, this mismatch disappears, which seems to confirm faster growth. Recruits of the 0-group and adults of age 4 (with the faster growth: ca. ∼57-65 cm) dominated, whereas the intermediate age groups were scarce on the bank. These results and recent findings from tag-and-recapture experiments suggest that white Anglerfish move to and from the Porcupine Bank, calling into question the stock boundaries currently accepted for the species in the North Atlantic.
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Anglerfish discard estimates and patterns in Spanish Northeast Atlantic trawl fisheries
ICES Journal of Marine Science, 2008Co-Authors: Paz Díaz, Francisco Velasco, Juan Santos, Alberto Serrano, Nélida PérezAbstract:Estimates of Spanish bottom trawl discards of Anglerfish Lophius budegassa and Lophius piscatorius in the Northeast Atlantic Ocean are presented. Both species are commercially valuable in ICES Subareas VI and VII, and Divisions VIIIc and IXa. Information was obtained from observers on board during discard-monitoring programmes. Raising by effort, rather than by landings and target species, was used to determine the total annual discards by weight and number, the discard percentage, and the discard length distribution by stock throughout the dataseries. By weight and number, discards varied interannually, ranging from 4 to 600 t (28 000 –7 000 000 fish) in northern stocks of Anglerfish, and from 1 to 100 t (20 000– 400 000 fish) in southern stocks. The discard percentage for both species and northern and southern stocks therefore ranged between 2 and 76% by number. Length distributions of the discarded Anglerfish show that most were juveniles, although the pattern differed in years with high or with low rates of discarding. The number of juveniles caught apparently increased in most areas after 2000. Correlations between the quantities discarded and recruitment indices from French and Irish trawl surveys were found for northern stocks and with Spanish trawl survey indices for southern stocks.
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Feeding ecology of black Anglerfish Lophius budegassa : seasonal, bathymetric and ontogenetic shifts
Journal of the Marine Biological Association of the United Kingdom, 2006Co-Authors: Izaskun Preciado, Francisco Velasco, Ignacio Olaso, Jorge LandaAbstract:The diet of black Anglerfish Lophius budegassa is described for the Cantabrian Sea (North Atlantic coast of Spain) from seasonal samples obtained onboard commercial vessels from January 1993 to December 1994. The stomach contents of fish caught on the continental shelf were examined, and differences in the diet in relation to age-class, season and depth were studied. The age-classes were grouped according to a cluster analysis of diet composition. As a result, three groups were obtained: the first two corresponded to juveniles between 2 and 7 years old, and the third one corresponded to adults between 8 and 15 years old. Although Micromesistius poutassou was an important prey for all ages, the youngest black Anglerfish fed mainly on small benthic fish. In contrast, large prey species such as Phycis blennoides and Merluccius merluccius were eaten almost exclusively by adults. The diet composition changed during the year. The changes in the diet of black Anglerfish older than 3 years were more related to seasonal differences than to between-size differences. These seasonal shifts were mainly marked by the varying importance of Trachurus trachurus and M. merluccius in their diet. Feeding intensity also showed seasonal variations, with a significant decrease in autumn. An indirect effect of depth on the feeding ecology of black Anglerfish was also found, since both age and diet composition changed with depth.
Iñaki Quincoces - One of the best experts on this subject based on the ideXlab platform.
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Movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in the northeast Atlantic
Fisheries Research, 2008Co-Authors: Jorge Landa, Rafael Duarte, Iñaki Quincoces, A.c. Fariña, Herve DupouyAbstract:Abstract Within the frame of an international tagging program which has been carried out since 1995, movements of black and white Anglerfish (Lophius budegassa and L. piscatorius) in Southern European waters were studied. This is the first large-scale study on movements of tagged black Anglerfish. A total of 877 black Anglerfish (6–88 cm total length) and 1326 white Anglerfish (15–137 cm total length) were tagged. Times at liberty ranged from 1 to 665 days, with recapture rates of 21 (2.4%) and 50 (3.8%), respectively. A description of our tagging procedures is presented, together with the influences of the gear used, fish length and area of tagging on recapture rates. The type of fishing gear was the main factor affecting recapture rates. Fish length was neither related to the displacement distance nor to the time at liberty while the displacement distance was related to the time at liberty. Recapture locations suggested that movements occurred both in- and offshore. The largest displacement recorded was 408 km of a black Anglerfish from southern to northern Bay of Biscay. The movements of the Anglerfish indicate a mixing between northern and southern populations which may have strong implications for the current geographical boundaries of the stocks from a management perspective. Here, movement of white Anglerfish between the Le Danois Bank and the Cantabrian continental shelf is reported for the first time.
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Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish
ICES Journal of Marine Science, 2007Co-Authors: Jorge Landa, Rafael Duarte, Iñaki QuincocesAbstract:Landa, J., Duarte, R., and Quincoces, I. 2008. Growth of white Anglerfish (Lophius piscatorius) tagged in the Northeast Atlantic, and a review of age studies on Anglerfish. - ICES Journal of Marine Science, 65: 72-80.Growth of white Anglerfish was estimated from the results of a tagging study in south European waters. In all, 1326 fish, caught by bottom trawl and gillnet commercial vessels and on trawl surveys, were tagged from 1995 to 2004; 50 were recovered, and a growth rate of 13.6 cm year −1 was estimated from the four fish at liberty long enough to allow extrapolation of the growth rate to an annual period. Growth patterns were reviewed based on available studies of growth verification of white Anglerfish in Atlantic waters, including another tag-recapture study, length-frequency of catches, and microstructure analysis of hard parts. The growth rate estimated from these studies showed many similarities, and an overall growth pattern was estimated: growth rate = 18.24e -0.015length . A von Bertalanffy growth curve fitted to all data yielded the parameter values L ∞ = 140 cm and k = 0.11. This growth rate is faster than estimated recently using illicia for age estimation, but similar to that found in the first studies that used illicia and sectioned otoliths. Current estimates of growth based on illicia, which are used in assessing the northern European stock of white Anglerfish, seem to be underestimated.
