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P L Pascoe - One of the best experts on this subject based on the ideXlab platform.
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the diet of sperm whales physeter macrocephalus linnaeus 1758 off the azores
Philosophical Transactions of the Royal Society B, 1993Co-Authors: M. R. Clarke, Helen R Martins, P L PascoeAbstract:Stomach contents from 17 sperm whales, 15 males and two females, caught during commercial activities in 1981-1984 in the Azores region were identified and measured. A total of 28 738 Cephalopods and 16 fish were represented in the collections. In addition, there were tunicates in two whales and man-made products in three whales. None of the stomachs were empty. Flesh was present in 94.1% and indigestible fragments alone, including mandibles (beaks) of Cephalopods, were present in 5.9% of the stomachs. Twelve species of Cephalopod were represented by flesh and 40 species were represented by lower beaks. The Cephalopod families contributing food to the whales in this region are, in order of their contribution by estimated mass, the Octopoteuthidae (39.8%), the Histioteuthidae (32.7%), the Architeuthidae (12.1%), the Lepidoteuthidae (4.5%), the Ommastrephidae (3.4%), the Pholidoteuthidae (2.1%), the Cycloteuthidae (1.9%), the Cranchiidae (1.7%) and eight other families each contributing less than 1% by mass. Presence of Gonatus beaks in the stomachs show which whales have migrated southwards to the Azores just prior to capture and the presence of a large Megalocranchia species possibly shows which whales have migrated from higher latitudes off Iceland. However, the presence of Teuthowenia maculata shows which whales came north from the West coast of Africa, just prior to capture. The modal mass of Cephalopods consumed is 400-450 g which represents 0.00001 of the whales' body mass. 77.5% of the species eaten have luminous organs and 82% of the species are neutrally buoyant. It seems likely that the sperm whale is obtaining 77% of its food by swimming through luminous shoals of slow-swimming, neutrally bouyant squids and only about 23% by chasing faster swimming, larger Cephalopods. Cephalopods not previously recorded from the North Atlantic are Onychoteuthis borealijaponicus, and Histioteuthis bonnellii corpuscula. Histioteuthis?miranda may have been collected by the whales much further south than the Azores. Species not recorded previously in the diet of sperm whales in the North Atlantic are Ommastrephes bartrami, Gonatus steenstrupi, Histioteuthis?miranda, H. bonnellii corpuscula, H. meleagroteuthis, Discoteuthis laciniosa, Mastigoteuthis species, Chiroteuthis species,?Helicocranchia, Liocranchia reinhardti, and?Liguriella.
Ángel Guerra - One of the best experts on this subject based on the ideXlab platform.
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wind driven upwelling effects on Cephalopod paralarvae octopus vulgaris and loliginidae off the galician coast ne atlantic
Progress in Oceanography, 2016Co-Authors: Jaime Otero, Angel F Gonzalez, Anton X Alvarezsalgado, Carlos Souto, Miguel Gilcoto, Ángel GuerraAbstract:Abstract Circulation patterns of coastal upwelling areas may have central consequences for the abundance and cross-shelf transport of the larval stages of many species. Previous studies have provided evidences that larvae distribution results from a combination of subtidal circulation, species-specific behaviour and larval sources. However, most of these works were conducted on organisms characterised by small-sized and abundant early life phases. Here, we studied the influence of the hydrography and circulation of the Ria de Vigo and adjacent shelf (NW Iberian upwelling system) on the paralarval abundance of two contrasting Cephalopods, the benthic common octopus ( Octopus vulgaris ) and the pelagic squids (Loliginidae). We sampled repeatedly a cross-shore transect during the years 2003–2005 and used zero inflated models to accommodate the scarcity and patchy distribution of Cephalopod paralarvae. The probability of catching early stages of both Cephalopods was higher at night. Octopus paralarvae were more abundant in the surface layer at night whereas loliginids preferred the bottom layer regardless of the sampling time. Abundance of both Cephalopods increased when shelf currents flowed polewards, water temperature was high and water column stability was low. The probability of observing an excess of zero catches decreased during the year for octopus and at high current speed for loliginids. In addition, the circulation pattern conditioned the body size distribution of both paralarvae; while the average size of the captured octopuses increased (decreased) with poleward currents at daylight (nighttime), squids were smaller with poleward currents regardless of the sampling time. These results contribute to the understanding of the effects that the hydrography and subtidal circulation of a coastal upwelling have on the fate of Cephalopod early life stages.
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Cephalopod biology and fisheries in europe
ed. by Pierce Graham J. Allcock Louise Bruno Isabel Bustamante Paco Gonzalez Angel Guerra Angel Jereb Patricia Lefkaditou Eugenia Malham Shelagh Moren, 2010Co-Authors: Graham J. Pierce, Ángel Guerra, Louise Allcock, Angel F Gonzalez, I Bruno, Paco Bustamante, P Jereb, E Lefkaditou, Shelagh K Malham, Ana MorenoAbstract:Over the past two decades, Cephalopod molluscs have attracted increased attention from marine biologists and fishery scientists. Several species are important for European fisheries, as targets of small‐scale coastal fisheries and/or as bycatch in multispecies fisheries for demersal fish. The present report draws on a series of reviews prepared in 2005 for the CEPHSTOCK project (see Section 1). The taxonomy of the main resource species is reviewed (Section 2), and brief descriptions of each species are provided, along with information from studies of population genetics, habitat requirements of paralarvae and adults, and health and ecotoxicology (Section 3). The main fisheries are described, including illustration of gears used in specialized small‐scale fisheries and a discussion of the socio‐economic importance of the fisheries. The current status of Cephalopod aquaculture is reviewed, highlighting notable advances in commercial culture of octopus and cuttlefish (Section 4). Current fishery data collection and fishery management are described, noting that there is no setting of landings quotas and no routine assessment of stock status. Options for stock assessment are discussed, drawing on one‐off assessments made during specific projects and current practice elsewhere in the world. The “live fast, die young” lifehistory strategies of Cephalopods present particular challenges, but parallels can be drawn with short‐lived fish (Section 5). Finally, the report looks to the future, reviewing possible effects of climate change on Cephalopods. It discusses the future development of aquaculture and fisheries for Cephalopods, including prospects for fishery forecasting and fishery management – especially in relation to the small‐scale directed fisheries. Various knowledge gaps are identified, and ideas for research to fill these gaps are presented.
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Feeding ecology of Cuvier's beaked whale (Ziphius cavirostris): A review with new information on the diet of this species
Journal of the Marine Biological Association of the United Kingdom, 2001Co-Authors: M. B. Santos, Jeremy S. Herman, Graham J. Pierce, Ángel Guerra, Alfredo López, Eleni Mente, M. R. ClarkeAbstract:Published information on the diet of Cuvier's beaked whales Ziphius cavirostris (Odontoceti: Ziphiidae) is reviewed and new information on the stomach contents of three animals: two stranded in Galicia (north-west Spain) in February 1990 at A Lanzada, and in February 1995 at Portonovo; and the third stranded in February 1999 in North Uist (Scotland), is presented. The whale stranded in 1990 was a male; the other two were adult females, All animals were > 5 m long. The limited published information on the diet of this species indicates that it feeds primarily on oceanic Cephalopods although some authors also found remains of oceanic fish and crustaceans. Food remains from the three new samples consisted entirely of Cephalopod beaks. The Scottish sample set is the largest recorded to date for this species. The prey identified consisted of oceanic Cephalopods, mainly squid (Cephalopoda: Teuthoidea). The most frequently occurring species were the squid Teuthowenia megalops, Mastigoteuthis schmidti and Taonius pavo (for the Galician whale stranded in 1990), Teuthowenia megalops and Histioteuthis reversa (for the second Galician whale) and T. megalops, Gonatus sp. and Taonius pavo (for the Scottish whale). Other prey included the squid Histioteuthis bonnellii, Histioteuthis arcturi and Todarodes sagittatus as well as Vampiroteuthis infernalis (Cephalopoda: Vampyromorpha), Stauroteuthis syrtensis and Japetella diaphana (Cephalopoda: Octopoda). The squid eaten (estimated from the measurement of the lower beaks) included juvenile and mature individuals of the most important species (Teuthowenia megalops, Gonatus sp.). The range of species found in the diet of Z. cavirostris is greater than that reported for sperm whales and bottlenosed whales in the north-east Atlantic.
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squid as trophic bridges for parasite flow within marine ecosystems the case of anisakis simplex nematoda anisakidae or when the wrong way can be right
African Journal of Marine Science, 1998Co-Authors: Elvira Abollo, C Gestal, Ángel Guerra, Alfredo López, Angel F Gonzalez, Santiago PascualAbstract:Long-term (1991–1997) information on parasitic infection by anisakid nematodes in Cephalopods and top predators (marine mammals) of the south-eastern area of the North Atlantic underlines the important role of small cetaceans as final hosts for A. simplex. The ommastrephid squid Illex couidetii, Todaropsis eblanae and Todarodes sagittatus are the most important Cephalopod paratenic hosts in the life cycle of the parasite. Information on parasite flow and parasite-caused diseases could be of use for stock assessment purposes. Moreover, it largely agrees with what is known about interactions between prey (squid) and predator (cetacean) in the same area. Parasitic castration and stomach wall ulceration were the most important parasite-caused effects recorded in infected Cephalopods and cetaceans respectively.
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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.
M. R. Clarke - One of the best experts on this subject based on the ideXlab platform.
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Feeding ecology of Cuvier's beaked whale (Ziphius cavirostris): A review with new information on the diet of this species
Journal of the Marine Biological Association of the United Kingdom, 2001Co-Authors: M. B. Santos, Jeremy S. Herman, Graham J. Pierce, Ángel Guerra, Alfredo López, Eleni Mente, M. R. ClarkeAbstract:Published information on the diet of Cuvier's beaked whales Ziphius cavirostris (Odontoceti: Ziphiidae) is reviewed and new information on the stomach contents of three animals: two stranded in Galicia (north-west Spain) in February 1990 at A Lanzada, and in February 1995 at Portonovo; and the third stranded in February 1999 in North Uist (Scotland), is presented. The whale stranded in 1990 was a male; the other two were adult females, All animals were > 5 m long. The limited published information on the diet of this species indicates that it feeds primarily on oceanic Cephalopods although some authors also found remains of oceanic fish and crustaceans. Food remains from the three new samples consisted entirely of Cephalopod beaks. The Scottish sample set is the largest recorded to date for this species. The prey identified consisted of oceanic Cephalopods, mainly squid (Cephalopoda: Teuthoidea). The most frequently occurring species were the squid Teuthowenia megalops, Mastigoteuthis schmidti and Taonius pavo (for the Galician whale stranded in 1990), Teuthowenia megalops and Histioteuthis reversa (for the second Galician whale) and T. megalops, Gonatus sp. and Taonius pavo (for the Scottish whale). Other prey included the squid Histioteuthis bonnellii, Histioteuthis arcturi and Todarodes sagittatus as well as Vampiroteuthis infernalis (Cephalopoda: Vampyromorpha), Stauroteuthis syrtensis and Japetella diaphana (Cephalopoda: Octopoda). The squid eaten (estimated from the measurement of the lower beaks) included juvenile and mature individuals of the most important species (Teuthowenia megalops, Gonatus sp.). The range of species found in the diet of Z. cavirostris is greater than that reported for sperm whales and bottlenosed whales in the north-east Atlantic.
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the diet of sperm whales physeter macrocephalus linnaeus 1758 off the azores
Philosophical Transactions of the Royal Society B, 1993Co-Authors: M. R. Clarke, Helen R Martins, P L PascoeAbstract:Stomach contents from 17 sperm whales, 15 males and two females, caught during commercial activities in 1981-1984 in the Azores region were identified and measured. A total of 28 738 Cephalopods and 16 fish were represented in the collections. In addition, there were tunicates in two whales and man-made products in three whales. None of the stomachs were empty. Flesh was present in 94.1% and indigestible fragments alone, including mandibles (beaks) of Cephalopods, were present in 5.9% of the stomachs. Twelve species of Cephalopod were represented by flesh and 40 species were represented by lower beaks. The Cephalopod families contributing food to the whales in this region are, in order of their contribution by estimated mass, the Octopoteuthidae (39.8%), the Histioteuthidae (32.7%), the Architeuthidae (12.1%), the Lepidoteuthidae (4.5%), the Ommastrephidae (3.4%), the Pholidoteuthidae (2.1%), the Cycloteuthidae (1.9%), the Cranchiidae (1.7%) and eight other families each contributing less than 1% by mass. Presence of Gonatus beaks in the stomachs show which whales have migrated southwards to the Azores just prior to capture and the presence of a large Megalocranchia species possibly shows which whales have migrated from higher latitudes off Iceland. However, the presence of Teuthowenia maculata shows which whales came north from the West coast of Africa, just prior to capture. The modal mass of Cephalopods consumed is 400-450 g which represents 0.00001 of the whales' body mass. 77.5% of the species eaten have luminous organs and 82% of the species are neutrally buoyant. It seems likely that the sperm whale is obtaining 77% of its food by swimming through luminous shoals of slow-swimming, neutrally bouyant squids and only about 23% by chasing faster swimming, larger Cephalopods. Cephalopods not previously recorded from the North Atlantic are Onychoteuthis borealijaponicus, and Histioteuthis bonnellii corpuscula. Histioteuthis?miranda may have been collected by the whales much further south than the Azores. Species not recorded previously in the diet of sperm whales in the North Atlantic are Ommastrephes bartrami, Gonatus steenstrupi, Histioteuthis?miranda, H. bonnellii corpuscula, H. meleagroteuthis, Discoteuthis laciniosa, Mastigoteuthis species, Chiroteuthis species,?Helicocranchia, Liocranchia reinhardti, and?Liguriella.
José C. Xavier - One of the best experts on this subject based on the ideXlab platform.
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A review on the biodiversity, distribution and trophic role of Cephalopods in the Arctic and Antarctic marine ecosystems under a changing ocean
Marine Biology, 2018Co-Authors: José C. Xavier, Yves Cherel, Rui Rosa, Louise Allcock, Rushan M. Sabirov, Martin E. Blicher, Alexey V. GolikovAbstract:Cephalopods play an important role in polar marine ecosystems. In this review, we compare the biodiversity, distribution and trophic role of Cephalopods in the Arctic and in the Antarctic. Thirty-two species have been reported from the Arctic, 62 if the Pacific Subarctic is included, with only two species distributed across both these Arctic areas. In comparison, 54 species are known from the Antarctic. These polar regions share 15 families and 13 genera of Cephalopods, with the giant squid Architeuthis dux the only species confirmed to occur in both the Arctic and Antarctic. Polar Cephalopods prey on crustaceans, fish, and other Cephalopods (including cannibalism), whereas predators include fish, other Cephalopods, seabirds, seals and whales. In terms of differences between the Cephalopod predators in the polar regions, more Antarctic seabird species feed on Cephalopods than Arctic seabirds species, whereas more Arctic mammal species feed on Cephalopods than Antarctic mammal species. Cephalopods from these regions are likely to be more influenced by climate change than those from the rest of the World: Arctic fauna is more subjected to increasing temperatures per se, with these changes leading to increased species ranges and probably abundance. Antarctic species are likely to be influenced by changes in (1) mesoscale oceanography (2) the position of oceanic fronts (3) sea ice extent, and (4) ocean acidification. Polar Cephalopods may have the capacity to adapt to changes in their environment, but more studies are required on taxonomy, distribution, ocean acidification and ecology.
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the Cephalopod prey of the weddell seal leptonychotes weddellii a biological sampler of the antarctic marine ecosystem
Polar Biology, 2016Co-Authors: Agustina Negri, A. Corbalán, G A Daneri, Filipe R. Ceia, Nestor Coria, Rui P. Vieira, Yves Cherel, José C. XavierAbstract:Weddell seals, Leptonychotes weddellii, are important apex predators in the food web of the Antarctic marine ecosystem. However, detailed information on their trophic relationships with Cephalopods is scarce. Moreover, Cephalopods play a key role in the marine environment, but knowledge of their feeding habits is limited by lack of data. Here, we have combined the use of this seal as a biological sampler together with measurements of the stable isotopic signature of the beaks of their Cephalopod prey. Thus, the aims of the present study were: (1) to examine in detail the Cephalopod portion of the diet of Weddell seals by means of scat analysis and (2) to assess the habitat use and trophic level of the different Cephalopod prey taxa identified. From January to February 2009, a total of 48 faecal droppings were collected at Hope Bay, Antarctic Peninsula. Cephalopods were mainly represented by beaks (n = 83) which were identified to the lowest possible taxonomic level. Furthermore, subsamples of beaks were separated for further isotopic analysis. Relative abundance of stable isotopes of carbon (δ13C) and nitrogen (δ15N) was determined by continuous-flow isotope-ratio mass spectrometry. Cephalopods were represented uniquely by octopods of the subfamily Eledoninae. Pareledone turqueti was the dominant prey species followed by the papillated Pareledone species group and Adelieledone polymorpha. We conclude that Weddell seals preyed primarily on benthic prey resources. Furthermore, the relatively similar δ13C and δ15N values in beaks of the three octopod prey taxa suggest that these share the same type of habitat and occupy similar trophic level positions.
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Cephalopod beak guide for the southern ocean
2009Co-Authors: José C. Xavier, Yves CherelAbstract:Cephalopods play an important role in the Antarctic ecosystem, being consumed by a wide range of predators such as whales, fish, seals, albatrosses and penguins. To understand predator-prey interactions between top predators and Cephalopods, effort has been put into the development of methods to determine the identity and size of world Cephalopods using beaks since the 1950s (Clarke 1962a, b; Clarke 1966; Clarke 1977; Clarke 1980; Clarke 1986; Kubodera & Furuhashi 1987; Fiscus 1991; Smale et al. 1993; Xavier et al. 2007). The most used beak guide worldwide (Clarke 1986) is now out of print and is in need of urgent revision with additional material (Santos et al. 2001). Also, several new Cephalopod species for the Southern Ocean have been recently described taxonomically, whose beaks need to be described and/or included in a guide (e.g. Collins & Henriques 2000; Lipinski 2001; Allcock & Piertney 2002). New efforts in the Southern Hemisphere allowed a new Cephalopod beak guide to be produced (Lu & Ickeringill 2002), covering 75 species of Cephalopods in Australian waters. Also new internet technology has been used to create a website to aid beak identification (http://research.kahaku.go.jp/zoology/Beak-E/index.htm) for Japanese waters. However, a Cephalopod beak guide for the entire Southern Ocean is nonexistent and urgently needed. Here, we specifically aim to describe the main Cephalopod beaks from species found in the diet of predators from the Southern Ocean (defined as south of the Subtropical Front) and adjacent waters in order to assist scientists and students interested in identifying Cephalopods by the means of their beaks. Special attention was paid to providing photographs of typical beaks found in the diets of adults and juveniles when relevant. As a new tool applied to marine ecology, 3-D computer images of the most important lower beaks are also provided, where it is possible to rotate each beak 360 degrees and zoom in and out of particular key features of beaks in three dimensions. In addition, a review of the allometric regressions available is provided in order to relate Cephalopod beak size to mantle length and mass as well as a review of the predators feeding on those Cephalopod species.
Helen R Martins - One of the best experts on this subject based on the ideXlab platform.
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the diet of sperm whales physeter macrocephalus linnaeus 1758 off the azores
Philosophical Transactions of the Royal Society B, 1993Co-Authors: M. R. Clarke, Helen R Martins, P L PascoeAbstract:Stomach contents from 17 sperm whales, 15 males and two females, caught during commercial activities in 1981-1984 in the Azores region were identified and measured. A total of 28 738 Cephalopods and 16 fish were represented in the collections. In addition, there were tunicates in two whales and man-made products in three whales. None of the stomachs were empty. Flesh was present in 94.1% and indigestible fragments alone, including mandibles (beaks) of Cephalopods, were present in 5.9% of the stomachs. Twelve species of Cephalopod were represented by flesh and 40 species were represented by lower beaks. The Cephalopod families contributing food to the whales in this region are, in order of their contribution by estimated mass, the Octopoteuthidae (39.8%), the Histioteuthidae (32.7%), the Architeuthidae (12.1%), the Lepidoteuthidae (4.5%), the Ommastrephidae (3.4%), the Pholidoteuthidae (2.1%), the Cycloteuthidae (1.9%), the Cranchiidae (1.7%) and eight other families each contributing less than 1% by mass. Presence of Gonatus beaks in the stomachs show which whales have migrated southwards to the Azores just prior to capture and the presence of a large Megalocranchia species possibly shows which whales have migrated from higher latitudes off Iceland. However, the presence of Teuthowenia maculata shows which whales came north from the West coast of Africa, just prior to capture. The modal mass of Cephalopods consumed is 400-450 g which represents 0.00001 of the whales' body mass. 77.5% of the species eaten have luminous organs and 82% of the species are neutrally buoyant. It seems likely that the sperm whale is obtaining 77% of its food by swimming through luminous shoals of slow-swimming, neutrally bouyant squids and only about 23% by chasing faster swimming, larger Cephalopods. Cephalopods not previously recorded from the North Atlantic are Onychoteuthis borealijaponicus, and Histioteuthis bonnellii corpuscula. Histioteuthis?miranda may have been collected by the whales much further south than the Azores. Species not recorded previously in the diet of sperm whales in the North Atlantic are Ommastrephes bartrami, Gonatus steenstrupi, Histioteuthis?miranda, H. bonnellii corpuscula, H. meleagroteuthis, Discoteuthis laciniosa, Mastigoteuthis species, Chiroteuthis species,?Helicocranchia, Liocranchia reinhardti, and?Liguriella.