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Antonio Barreiro - One of the best experts on this subject based on the ideXlab platform.
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diets of marine mammals stranded on the northwestern spanish atlantic coast with special reference to cephalopoda
Fisheries Research, 1994Co-Authors: Angel F Gonzalez, Ángel Guerra, Alfredo López, Antonio BarreiroAbstract:Abstract Stomach contents from 59 marine mammals, 28 Delphinus delphis , 14 Tursiops truncatus , three Grampus griseus , four Stenella coeruleoalba , three Globicephala melas , one Ziphius cavirostris , four Phocoena phocoena , one Physeter macrocephalus and one Balaenoptera acutorostrata stranded on the northwestern Spanish Atlantic coast from December 1990 to March 1993 were examined. A total of 9076 fish otoliths and 654 cephalopod upper and lower beaks were collected. The otoliths were identified only to family level, representing by number 65% Gadidae, 24% Gobiidae, 6% Atherinidae, 2% Ammodytidae, 1.5% Clupeidae and the rest Carangidae, Labridae, Argentinidae, Macroramphosidae and Bothidae. The cephalopod beaks belonged to 12 species of nine families. The cephalopod families contributing food of these marine mammals, in order of contribution by number of specimens are, the Loliginidae (56.9%), the Octopodidae (25.3%), the Ommastrephidae (11.9%), the Sepiolidae (2.4%), the Histioteuthidae (0.9%), the Chiroteuthidae (0.9%), the Cranchiidae (0.8%), the Mastigoteuthidae (0.3%) and the Gonatidae (0.15%). The great part of the cephalopods observed in the stomach contents were small in size, except for some octopods in Grampus griseus and Globicephala melas , and Mastigoteuthis sp. in Physeter macrocephalus . The results indicated that D. delphis, T. truncatus and Phocoena phocoena are primarily fish-eating, while Grampus griseus, Globicephala melas and Physeter macrocephalus had only cephalopod remains in their stomachs.
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Diets of marine mammals stranded on the northwestern Spanish Atlantic coast with special reference to Cephalopoda
Fisheries Research, 1994Co-Authors: Angel F Gonzalez, Antonio BarreiroAbstract:13 páginas, 4 tablas, 1 apéndiceStomach contents from 59 marine mammals, 28 Delphinus delphis, 14 Tursiops truncatus, three Grampus griseus, four Stenella coeruleoalba, three Globicephala melas, one Ziphius cavirostris, four Phocoena phocoena, one Physeter macrocephalus and one Balaenoptera acutorostrata stranded on the northwestern Spanish Atlantic coast from December 1990 to March 1993 were examined.\ud \ud A total of 9076 fish otoliths and 654 cephalopod upper and lower beaks were collected. The otoliths were identified only to family level, representing by number 65% Gadidae, 24% Gobiidae, 6% Atherinidae, 2% Ammodytidae, 1.5% Clupeidae and the rest Carangidae, Labridae, Argentinidae, Macroramphosidae and Bothidae. The cephalopod beaks belonged to 12 species of nine families. The cephalopod families contributing food of these marine mammals, in order of contribution by number of specimens are, the Loliginidae (56.9%), the Octopodidae (25.3%), the Ommastrephidae (11.9%), the Sepiolidae (2.4%), the Histioteuthidae (0.9%), the Chiroteuthidae (0.9%), the Cranchiidae (0.8%), the Mastigoteuthidae (0.3%) and the Gonatidae (0.15%). The great part of the cephalopods observed in the stomach contents were small in size, except for some octopods in Grampus griseus and Globicephala melas, and Mastigoteuthis sp. in Physeter macrocephalus. The results indicated that D. delphis, T. truncatus and Phocoena phocoena are primarily fish-eating, while Grampus griseus, Globicephala melas and Physeter macrocephalus had only cephalopod remains in their stomachs.This work\ud was funded by the Commission of the European Communities within the frame\ud of this EEC research programme in the fisheries sector (FAR, contract no. MA\ud 1.146).Peer reviewe
Graham J. Pierce - One of the best experts on this subject based on the ideXlab platform.
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variability in the diet of harbor porpoises phocoena phocoena in scottish waters 1992 2003
Marine Mammal Science, 2004Co-Authors: M B Santos, Graham J. Pierce, J A Learmonth, R J Reid, H M Ross, I A P Patterson, David G Reid, Doug BeareAbstract:Interannual, seasonal, and regional variation in the diet of porpoises, Phocoena phocoena, in Scottish (UK) waters was studied using stomach contents of animals stranded between 1992 and 2003. Most samples came from the east coast (including many porpoises killed by bottlenose dolphins), with smaller numbers from the west coast and from Shetland. The most important prey types, in terms of contribution by number and mass, were whiting (Merlangius merlangus) and sand eels (Ammodytidae). Multivariate analysis confirmed the existence of regional, seasonal, and interannual variation in diet, as well as differences (i.e., biases) related to cause of death. These differences were further explored using univariate analyses. Sand eels were more important in the summer months (quarters 2 and 3) and on the east coast, whereas gadids were more important in winter and in the Shetland area. Some, but not all, observed trends in the numerical importance and size of prey taken were consistent with trends in abundance and size of fish
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the diet of harbour porpoise phocoena phocoena in the northeast atlantic
Oceanography and Marine Biology, 2003Co-Authors: M B Santos, Graham J. PierceAbstract:The harbour porpoise (Phocoena phocoena) is probably the most abundant small cetacean in the northeast Atlantic and as such is an important top predator. It is also one of the most threatened species, particularly as a consequence of fishery by-catch. Porpoises feed mainly on small shoaling fishes from both demersal and pelagic habitats. Many prey items are probably taken on, or very close to, the sea bed. Even though a wide range of species has been recorded in the diet, porpoises in any one area tend to feed primarily on two to four main species (e.g. whiting ( Merlangius merlangus) and sandeels (Ammodytidae) in Scottish waters). Evidence for selective predation is equivocal. Many studies provide evidence of geographic, seasonal, interannual, ontogenetic or sexual differences in prey types or prey sizes, and such dif- ferences are often (speculatively) interpreted in terms of prey availability. A few studies demon- strate trends in diet selection that are consistent with changes in prey abundance. However, lack of availability of prey abundance data at an appropriate spatial and temporal scale is often a problem. Porpoise diets overlap extensively with diets of other piscivorous marine predators (notably seals). Many of the main prey species are also taken by commercial fisheries, although por- poises tend to take smaller fishes than those targeted by fisheries. Given their high abundance, porpoises clearly remove substantial quantities of fish. The literature on porpoise diets in the northeast Atlantic suggests that there has been a long- term shift from predation on clupeid fish (mainly herring Clupea harengus) to predation on sandeels and gadoid fish, possibly related to the decline in herring stocks since the mid-1960s. Evidence from studies on seals suggests that such a shift could have adverse health con- sequences. Food consumption brings porpoises into contact with two important threats - persistent organic contaminants and fishing nets, both of which have potentially serious impacts.
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Diets of squid Loligo forbesi and Loligo vulgaris in the northeast Atlantic
Fisheries Research, 1994Co-Authors: Graham J. Pierce, Peter Boyle, Lee C. Hastie, M. Begofia SantosAbstract:Abstract Diets of the loliginid squid Loligo forbesi and Loligo vulgaris were investigated by stomach contents sampling during 1990–1993. Monthly samples of Loligo forbesi were collected at Aberdeen and additional samples were obtained from the Irish Sea, Faroe, the English Channel, Vigo, Lisbon and the Azores. Samples of Loligo vulgaris were obtained from Vigo, Barcelona, Lisbon and Faro. Loligo forbesi feeds primarily on fishes, crustaceans and cephalopods. In Scottish waters, Gadidae (mainly Merlangius merlangus and Trisopterus sp.), Ammodytidae and Clupeidae were the most frequently identified prey. The relative importance of fish was slightly higher, and that of crustaceans lower, in the diet of larger squid. Gadidae and Clupeidae were more prominent in the winter diet, with sandeels being taken more frequently in the summer. The same prey taxa were important in the diet of Loligo forbesi across all areas. Fishes occurred in more than 80% of non-empty stomachs except for the Lisbon sample, in which crustaceans were the most frequently identified prey taxon. The species composition of the diet varied between areas. Thus, scad Trachurus picturatus was the most important prey in the Azores. The broad composition of the diet in Loligo vulgaris was similar, although crustaceans were apparently less important, but there were differences in species eaten between areas, and between the two Loligo species. Samples of the ommastrephid squid Todaropsis eblanae taken at Aberdeen indicated that this species was also primarily piscivorous, taking Gadidae and Clupeidae.
Angel F Gonzalez - One of the best experts on this subject based on the ideXlab platform.
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diets of marine mammals stranded on the northwestern spanish atlantic coast with special reference to cephalopoda
Fisheries Research, 1994Co-Authors: Angel F Gonzalez, Ángel Guerra, Alfredo López, Antonio BarreiroAbstract:Abstract Stomach contents from 59 marine mammals, 28 Delphinus delphis , 14 Tursiops truncatus , three Grampus griseus , four Stenella coeruleoalba , three Globicephala melas , one Ziphius cavirostris , four Phocoena phocoena , one Physeter macrocephalus and one Balaenoptera acutorostrata stranded on the northwestern Spanish Atlantic coast from December 1990 to March 1993 were examined. A total of 9076 fish otoliths and 654 cephalopod upper and lower beaks were collected. The otoliths were identified only to family level, representing by number 65% Gadidae, 24% Gobiidae, 6% Atherinidae, 2% Ammodytidae, 1.5% Clupeidae and the rest Carangidae, Labridae, Argentinidae, Macroramphosidae and Bothidae. The cephalopod beaks belonged to 12 species of nine families. The cephalopod families contributing food of these marine mammals, in order of contribution by number of specimens are, the Loliginidae (56.9%), the Octopodidae (25.3%), the Ommastrephidae (11.9%), the Sepiolidae (2.4%), the Histioteuthidae (0.9%), the Chiroteuthidae (0.9%), the Cranchiidae (0.8%), the Mastigoteuthidae (0.3%) and the Gonatidae (0.15%). The great part of the cephalopods observed in the stomach contents were small in size, except for some octopods in Grampus griseus and Globicephala melas , and Mastigoteuthis sp. in Physeter macrocephalus . The results indicated that D. delphis, T. truncatus and Phocoena phocoena are primarily fish-eating, while Grampus griseus, Globicephala melas and Physeter macrocephalus had only cephalopod remains in their stomachs.
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Diets of marine mammals stranded on the northwestern Spanish Atlantic coast with special reference to Cephalopoda
Fisheries Research, 1994Co-Authors: Angel F Gonzalez, Antonio BarreiroAbstract:13 páginas, 4 tablas, 1 apéndiceStomach contents from 59 marine mammals, 28 Delphinus delphis, 14 Tursiops truncatus, three Grampus griseus, four Stenella coeruleoalba, three Globicephala melas, one Ziphius cavirostris, four Phocoena phocoena, one Physeter macrocephalus and one Balaenoptera acutorostrata stranded on the northwestern Spanish Atlantic coast from December 1990 to March 1993 were examined.\ud \ud A total of 9076 fish otoliths and 654 cephalopod upper and lower beaks were collected. The otoliths were identified only to family level, representing by number 65% Gadidae, 24% Gobiidae, 6% Atherinidae, 2% Ammodytidae, 1.5% Clupeidae and the rest Carangidae, Labridae, Argentinidae, Macroramphosidae and Bothidae. The cephalopod beaks belonged to 12 species of nine families. The cephalopod families contributing food of these marine mammals, in order of contribution by number of specimens are, the Loliginidae (56.9%), the Octopodidae (25.3%), the Ommastrephidae (11.9%), the Sepiolidae (2.4%), the Histioteuthidae (0.9%), the Chiroteuthidae (0.9%), the Cranchiidae (0.8%), the Mastigoteuthidae (0.3%) and the Gonatidae (0.15%). The great part of the cephalopods observed in the stomach contents were small in size, except for some octopods in Grampus griseus and Globicephala melas, and Mastigoteuthis sp. in Physeter macrocephalus. The results indicated that D. delphis, T. truncatus and Phocoena phocoena are primarily fish-eating, while Grampus griseus, Globicephala melas and Physeter macrocephalus had only cephalopod remains in their stomachs.This work\ud was funded by the Commission of the European Communities within the frame\ud of this EEC research programme in the fisheries sector (FAR, contract no. MA\ud 1.146).Peer reviewe
M B Santos - One of the best experts on this subject based on the ideXlab platform.
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variability in the diet of harbor porpoises phocoena phocoena in scottish waters 1992 2003
Marine Mammal Science, 2004Co-Authors: M B Santos, Graham J. Pierce, J A Learmonth, R J Reid, H M Ross, I A P Patterson, David G Reid, Doug BeareAbstract:Interannual, seasonal, and regional variation in the diet of porpoises, Phocoena phocoena, in Scottish (UK) waters was studied using stomach contents of animals stranded between 1992 and 2003. Most samples came from the east coast (including many porpoises killed by bottlenose dolphins), with smaller numbers from the west coast and from Shetland. The most important prey types, in terms of contribution by number and mass, were whiting (Merlangius merlangus) and sand eels (Ammodytidae). Multivariate analysis confirmed the existence of regional, seasonal, and interannual variation in diet, as well as differences (i.e., biases) related to cause of death. These differences were further explored using univariate analyses. Sand eels were more important in the summer months (quarters 2 and 3) and on the east coast, whereas gadids were more important in winter and in the Shetland area. Some, but not all, observed trends in the numerical importance and size of prey taken were consistent with trends in abundance and size of fish
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the diet of harbour porpoise phocoena phocoena in the northeast atlantic
Oceanography and Marine Biology, 2003Co-Authors: M B Santos, Graham J. PierceAbstract:The harbour porpoise (Phocoena phocoena) is probably the most abundant small cetacean in the northeast Atlantic and as such is an important top predator. It is also one of the most threatened species, particularly as a consequence of fishery by-catch. Porpoises feed mainly on small shoaling fishes from both demersal and pelagic habitats. Many prey items are probably taken on, or very close to, the sea bed. Even though a wide range of species has been recorded in the diet, porpoises in any one area tend to feed primarily on two to four main species (e.g. whiting ( Merlangius merlangus) and sandeels (Ammodytidae) in Scottish waters). Evidence for selective predation is equivocal. Many studies provide evidence of geographic, seasonal, interannual, ontogenetic or sexual differences in prey types or prey sizes, and such dif- ferences are often (speculatively) interpreted in terms of prey availability. A few studies demon- strate trends in diet selection that are consistent with changes in prey abundance. However, lack of availability of prey abundance data at an appropriate spatial and temporal scale is often a problem. Porpoise diets overlap extensively with diets of other piscivorous marine predators (notably seals). Many of the main prey species are also taken by commercial fisheries, although por- poises tend to take smaller fishes than those targeted by fisheries. Given their high abundance, porpoises clearly remove substantial quantities of fish. The literature on porpoise diets in the northeast Atlantic suggests that there has been a long- term shift from predation on clupeid fish (mainly herring Clupea harengus) to predation on sandeels and gadoid fish, possibly related to the decline in herring stocks since the mid-1960s. Evidence from studies on seals suggests that such a shift could have adverse health con- sequences. Food consumption brings porpoises into contact with two important threats - persistent organic contaminants and fishing nets, both of which have potentially serious impacts.
Doug Beare - One of the best experts on this subject based on the ideXlab platform.
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variability in the diet of harbor porpoises phocoena phocoena in scottish waters 1992 2003
Marine Mammal Science, 2004Co-Authors: M B Santos, Graham J. Pierce, J A Learmonth, R J Reid, H M Ross, I A P Patterson, David G Reid, Doug BeareAbstract:Interannual, seasonal, and regional variation in the diet of porpoises, Phocoena phocoena, in Scottish (UK) waters was studied using stomach contents of animals stranded between 1992 and 2003. Most samples came from the east coast (including many porpoises killed by bottlenose dolphins), with smaller numbers from the west coast and from Shetland. The most important prey types, in terms of contribution by number and mass, were whiting (Merlangius merlangus) and sand eels (Ammodytidae). Multivariate analysis confirmed the existence of regional, seasonal, and interannual variation in diet, as well as differences (i.e., biases) related to cause of death. These differences were further explored using univariate analyses. Sand eels were more important in the summer months (quarters 2 and 3) and on the east coast, whereas gadids were more important in winter and in the Shetland area. Some, but not all, observed trends in the numerical importance and size of prey taken were consistent with trends in abundance and size of fish