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Registros recuperados: 134 | |
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Chassot, E; Rouyer, Tristan; Trenkel, Verena; Gascuel, D. |
The trophic level mean and variance, and the degree of omnivory for five Celtic Sea fish predators were estimated using a database of stomach content records characterized by a high level of taxonomic resolution. The predators occupied a high position in the food web, i.e. 4.75 for Atlantic cod Gadus morhua, 444 for haddock Melanogrammus aeglefinus, 4.88 for European hake Merluccius merluccius, 5.00 for megrim Lepidorhombus whiffiagonis and 5.27 for whiting Merlangius merlangus. The level of taxonomic resolution of the prey did not greatly affect mean T-L predator values; an effect on variance was evident, low resolution masking intra-population variability in T-L. Generalized additive models (GAM) were used to explain the variability of predator T-L... |
Tipo: Text |
Palavras-chave: Trophic level; Predation; Omnivory; Indicator; GAM; Food web. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4699.pdf |
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Reynolds, Pamela L.; Stachowicz, John J.; Hovel, Kevin; Bostrom, Christoffer; Boyer, Katharyn; Cusson, Mathieu; Eklof, Johan S.; Engel, Friederike G.; Engelen, Aschwin H.; Eriksson, Britas Klemens; Fodrie, F. Joel; Griffin, John N.; Hereu, Clara M.; Hori, Masakazu; Hanley, Torrance C.; Ivanov, Mikhail; Jorgensen, Pablo; Kruschel, Claudia; Lee, Kun-seop; Mcglathery, Karen; Moksnes, Per-olav; Nakaoka, Masahiro; O'Connor, Mary I.; O'Connor, Nessa E.; Orth, Robert J.; Rossi, Francesca; Ruesink, Jennifer; Sotka, Erik E.; Thormar, Jonas; Tomas, Fiona; Unsworth, Richard K. F.; Whalen, Matthew A.; Duffy, J. Emmett. |
Latitudinal gradients in species interactions are widely cited as potential causes or consequences of global patterns of biodiversity. However, mechanistic studies documenting changes in interactions across broad geographic ranges are limited. We surveyed predation intensity on common prey (live amphipods and gastropods) in communities of eelgrass (Zostera marina) at 48 sites across its Northern Hemisphere range, encompassing over 37 degrees of latitude and four continental coastlines. Predation on amphipods declined with latitude on all coasts but declined more strongly along western ocean margins where temperature gradients are steeper. Whereas insitu water temperature at the time of the experiments was uncorrelated with predation, mean annual... |
Tipo: Text |
Palavras-chave: Biogeography; Latitude; Mesograzer; Predation; Seagrass; Species interactions; Temperature; Zostera. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00610/72246/71053.pdf |
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Marques, Raquel; Bouvier, Corinne; Darnaude, Audrey M.; Molinero, Juan-carlos; Przybyla, Cyrille; Soriano, Solenn; Tomasini, Jean-antoine; Bonnet, Delphine. |
Although scientific interest on jellyfish ecology has substantially increased in the last decades, little is known on the role of potential predators shaping their population dynamics. Jellyfish were long considered as ‘dead ends’ within food webs, and therefore overlooked as potential food source for higher trophic levels, e.g. fishes. Here this question is tackled by using comprehensive laboratory experiments assessing fish predation on jellyfish. The approach included all the life stages (polyps, ephyrae and medusa) of Aurelia sp. versus more traditional aquaculture feeds in an easily farmed opportunistic fish, the gilthead seabream Sparus aurata (L.). Results revealed that all life stages of Aurelia sp. were accepted as a source of food by S. aurata,... |
Tipo: Text |
Palavras-chave: Aurelia sp.; Predation; Fish; Sparus aurata; Ingestion rate; Energy pathways. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00349/46018/46026.pdf |
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Benoit, Eric; Rochet, Marie-joelle. |
A new time-dependent continuous model of biomass size spectra is developed. In this model, predation is the single process governing the energy flow in the ecosystem, as it causes both growth and mortality. The ratio of predator to prey is assumed to be distributed: predators may feed on a range of prey sizes. Under these assumptions, it is shown that linear size spectra are stationary solutions of the model. Exploited fish communities are simulated by adding fishing mortality to the model: it is found that realistic fishing should affect the curvature and stability of the size spectrum rather than its slope. |
Tipo: Text |
Palavras-chave: Predation; Mortality; Growth; Biomass size spectrum; Allometry. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-665.pdf |
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Roussel, Sabine; Bisch, T; Lachambre, S; Boudry, Pierre; Gervois, Jl; Lambert, Christophe; Huchette, S; Day, R. |
Domestication of Haliotis tuberculata has only recently begun. During the process, we expect that behavioural and physiological traits may evolve to become more adapted to their captive environment. These modifications may result from intentional selection of production traits or unconscious and unintentional selection due to conditions experienced in the farm environment. To study this process at the earliest stage, the progeny of 3 different broodstocks obtained from wild parents, selected farmed abalone and randomly sampled farmed abalone, were studied. After rearing for 16 mo in separate tanks, offspring from the 3 progenies were placed together in sea cages at the same density. After 3 yr, behavioural traits were studied, and the immune status after a... |
Tipo: Text |
Palavras-chave: Predation; Hiding behaviour; Haliotis tuberculata; Domestication; Selection; Captive; Abalone. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00487/59841/62989.pdf |
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Rosecchi, E; Nouaze, Y. |
Compound indices are often used in the analysis of fish stomach contents to characterize diet. Five of these indices, combining two or three measures of prey importance: weight, abundance and frequency of occurrence, are mathematically compared in this work. Data from a feeding study of sparid fish show that different indices can produce different results. Four classifications of food, in terms of preferences, are applied to Sparidae, compared and discussed. A new method of classifying the prey of fish into groups is proposed. It characterizes the main items in the diet, whatever feeding index is chosen for the analysis. |
Tipo: Text |
Palavras-chave: Quantitative distribution; Weight; Predation; Stomach content; Feeding. |
Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/publication-1773.pdf |
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Goulletquer, Philippe. |
NOAA’s National Marine Fisheries Services (NMFS) received a petition to list the Eastern oyster (Crassostrea virginica) as either threatened or endangered under the Endangered Species Act (ESA). The Eastern oyster is an emblematic species in the US coastal states, playing a significant role at various levels: shaping coastal social communities, providing a commercial activity (public fishery & aquaculture) and recreational - amenity benefits, and as a keystone species in highly diverse and sensitive ecosystems (estuaries). This petition is likely the result of concerns regarding the partial collapse of public fisheries in several states as well as from the resulting damages to this species induced by severe hurricanes. A Biological Review Team (BRT)... |
Tipo: Text |
Palavras-chave: Biology; Habitat threats; Predation; Disease; Bivalvia; Crassostrea virginica; Oyster; Recommendations. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/00043/15458/12833.pdf |
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Gueroun, Sonai M; Molinero, Juan-carlos; Piraino, Stefano; Dali Yahia, Mohamed Nejib. |
Understanding the life cycle strategies and predatory impact of alien jellyfish species is critical to mitigate the impact that these organisms may have on local populations, biodiversity, and ultimately on the functioning of food webs. In the Mediterranean Sea, little is known about the dynamics of alien jellyfish, despite this biodiversity hotspot being one of the most threatened areas by increasing numbers of alien jellyfish. Here, we investigated the population dynamics and predatory impact of a non-indigenous scyphomedusa, Aurelia solida Browne 1905, in the Bizerte Lagoon, Tunisia. The study was based on bimonthly surveys performed over two consecutive years, from November 2012 to August 2014. Field observations showed that the planktonic phase of A.... |
Tipo: Text |
Palavras-chave: Scyphomedusae; Abundance; Predation; Mesozooplankton; SW Mediterranean. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00624/73577/72966.pdf |
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Quevedo, M; Gonzalez-quiros, R; Anadon, R. |
A large proliferation of Noctiluca scintillans (Dinophyceae: Noctilucidea) was observed in neritic waters off the central Cantabrian coast during late April 1995. Eggs of Acartia clausi (Crustacea: Copepoda) were the most conspicuous prey within vacuoles of Noctiluca. Noctiluca ingested 73 % of the total stock of A. clausi eggs. This intense predation on copepod eggs could potentially affect the recruitment of nauplii. The potential impact on the stock of Acartia clausi eggs and on the daily egg production of the population is discussed. There is a negative correlation between the average number of ingested eggs by a single Noctiluca cell and the abundance of Noctiluca. This fact, coupled with the lack of significant correlation between the former variable... |
Tipo: Text |
Palavras-chave: Noctiluca; Acartia; Œufs de copépode; Prédation; Golfe de Gascogne; Noctiluca; Acartia; Copepod eggs; Predation; Bay of Biscay. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43633/43232.pdf |
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Robert, Rene; Deltreil, Jean-pierre. |
Farming of the Japanese clam Ruditapes philippinarum took place for the first time in 1980 in the Arcachon basin. After an experimentation period of about ten years, a farming strategy, taking into consideration the distinctive features found in the bay, was able to emerge. For example, in order to fight against clam predators, crabs such as Carcinus maenas, and balistes such as Balistes capriscus, vertical protection coupled with prior ground gravelling, and laying of nets over the beds during the summer months, have become necessary. The best raising technique seems to rest on early spring planting of middle size spats (T5), after checking that no brown rings are visible. If clam growth seems to be better in oceanic zones, it looks similar in other areas... |
Tipo: Text |
Palavras-chave: Basin of Arcachon; Culture methods; Growth; Predation; Balistes capriscus; Carcinus maenas; Ruditapes philippinarum; Bassin d'Arcachon; Stratégie d'élevage; Croissance; Prédation; Balistes capriscus; Carcinus maenas; Ruditapes philippinarum. |
Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/1990/rapport-1652.pdf |
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Pechenik, Jan; Blanchard, Michel; Rotjan, Randi. |
The slipper shell snail Crepidula fornicata forms dense assemblages along much of the European coast, where it co-occurs with oysters. We examined the susceptibility of slipper shell larvae to predation by suspension-feeders, including adults of their own species. In particular, we compared filtration rates on phytoplankton with those on larvae, and determined the extent to which consumption of larvae varied with adult size, larval size, and with the presence of alternative food (phytoplankton). We also examined the ability of competent larvae to metamorphose successfully in the presence of feeding adults. For each experiment, adults were held in plastic jars with seawater or phytoplankton suspension and allowed to graze on larvae (101 larvae per jar) for... |
Tipo: Text |
Palavras-chave: Larvae; Susceptibility; Predation. |
Ano: 2004 |
URL: https://archimer.ifremer.fr/doc/2004/publication-755.pdf |
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Mazurie, Joseph; Stanisiere, Jean-yves; Bouget, Jean-francois; Langlade, Aime; Leclerc, Emilie; Quinsat, Kevin; Herve, Gilles; Augustin, Jean-marie; Ehrhold, Axel; Sinquin, Jean-marc; Meidi-deviarni, Ika; Goubert, Evelyne; Cochet, Helene; Dreano, Alain. |
This study (“Risco”), implicating both industry, socio-economic experts and biologists, was funded by the Regional Council of Brittany, for 3 years (2010-2012), to investigate about the causes of oysters (Crassostrea gigas) mortalities in the bay of Quiberon (South Brittany, France). The protocol including both a sonar and video visualization of the bottom, and a monthly survey of 15 experimental oyster structures, allowed to assess the risk due to predation. A clear spatial distribution of the predatory effect was evidenced, with starfish (Asterias rubens and Marthasterias glacialis) predominating in the North-East sector, and boring snails (Ocenebra erinacea and Pterophora inornata) in the South-Center area.. The main mortalities from these predators... |
Tipo: Text |
Palavras-chave: Baie de Quiberon; Huître; Crassostrea gigas; Risque; Mortalité; Prédation; Étoiles de mer; Bigorneaux perceurs; Risco; Bay of Quiberon; Oyster; Crassostrea gigas; Risk; Mortality; Predation; Starfish; Oyster drills; Risco. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00180/29130/27534.pdf |
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Nekaris,K Anne-Isola; Moore,Richard S; Rode,E Johanna; Fry,Bryan G. |
Only seven types of mammals are known to be venomous, including slow lorises (Nycticebus spp.). Despite the evolutionary significance of this unique adaptation amongst Nycticebus, the structure and function of slow loris venom is only just beginning to be understood. Here we review what is known about the chemical structure of slow loris venom. Research on a handful of captive samples from three of eight slow loris species reveals that the protein within slow loris venom resembles the disulphide-bridged heterodimeric structure of Fel-d1, more commonly known as cat allergen. In a comparison of N. pygmaeus and N. coucang, 212 and 68 compounds were found, respectively. Venom is activated by combining the oil from the brachial arm gland with saliva, and can... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Venoms; Ecology; Primates; Intraspecific competition; Predation; Ectoparasite; Naja naja. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992013000100203 |
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Rode-Margono, E.J.; Nekaris, K.A.-I.. |
Predation pressure, food availability, and activity may be affected by level of moonlight and climatic conditions. While many nocturnal mammals reduce activity at high lunar illumination to avoid predators (lunarphobia), most visually-oriented nocturnal primates and birds increase activity in bright nights (lunarphilia) to improve foraging efficiency. Similarly, weather conditions may influence activity level and foraging ability. We examined the response of Javan slow lorises (Nycticebus javanicus Geoffroy, 1812) to moonlight and temperature. We radio-tracked 12 animals in West Java, Indonesia, over 1.5 years, resulting in over 600 hours direct observations. We collected behavioural and environmental data including lunar illumination, number of human... |
Tipo: Article / Letter to the editor |
Palavras-chave: Activity; Environmental factors; Humidity; Lunarphobia; Moon; Predation; Temperature; 42.84. |
Ano: 2014 |
URL: http://www.repository.naturalis.nl/record/499291 |
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Vermeij, Geerat J.. |
Predation is a primary agency of natural selection affecting the evolution of skeletal form in gastropods. The nature of antipredatory defence depends on how predators attack their prey as well as on the types and quantities of resources that are available to the potential victims. Here I review the five main methods of predation on shell-bearing gastropods (swallowing prey whole, apertural entry, drilling, shell breakage, and partial consumption) and 31 categories of shell and opercular defence that are effective at one or more of the three stages of predation (detection, pursuit, and subjugation). These categories are evaluated for marine Palaeozoic, marine Late Mesozoic to Recent, freshwater, and terrestrial environments. The five types of... |
Tipo: Article / Letter to the editor |
Palavras-chave: Mollusca; Gastropoda; Predation; Antipredatory defence. |
Ano: 2015 |
URL: http://www.repository.naturalis.nl/record/588036 |
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Bergamin, Susan; Smits, Anne. |
Predators of asymmetric prey (such as snails) are often asymmetric themselves or display a predation behaviour that is adapted to the asymmetry of their prey. We studied predation of sinistral and dextral forms of the freshwater snail Lymnaea stagnalis (Linnaeus, 1758) by two snail-feeding beetle species, Phosphuga atrata (Linnaeus, 1758) and Carabus granulatus Linnaeus, 1758. We investigated a possible preference for or more efficient predation of prey items with a certain coiling direction. We found that C. granulatus displayed a preference for dextral snails, as opposed to P. atrata, which did not show any preference. We also looked at the asymmetry of the mandibles. In C. granulatus the left mandible overlay the right one in a higher... |
Tipo: Article / Letter to the editor |
Palavras-chave: Carabidae; Silphidae; Lymnaea stagnalis; Molluscivory; Chirality; Predation; Behaviour; Mouth parts. |
Ano: 2015 |
URL: http://www.repository.naturalis.nl/record/588051 |
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I made use of the known dates of reclamation (and of afforestations) in the IJsselmeerpolders in The Netherlands to assess evolutionary adaptation in Cepaea nemoralis. At 12 localities (three in each polder), I sampled a total of 4390 adult individuals in paired open and shaded habitats, on average 233m apart, and scored these for genetic shell colour polymorphisms. The results show (highly) significant differentiation at most localities, although the genes involved differed per locality. Overall, though, populations in shaded habitats had evolved towards darker shells than those in adjacent open habitats, whereas a 'Cain & Sheppard' diagram (proportion yellow shells plotted against ‘effectively unbanded’ shells) failed to reveal a clear pattern. This might suggest that thermal selection is more important than visual selection in generating this pattern. Trait differentiation, regardless of whether they were plotted against polder age or habitat age, showed a linear increase of differentiation with time, corresponding to a mean rate of trait evolution of 15–31 kilodarwin. In conclusion, C. nemoralis is capable of rapid and considerable evolutionary differentiation over 1–25 snail generations, though equilibrium may be reached only at longer time scales
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Naturalis | |
Schilthuizen, M.. |
I made use of the known dates of reclamation (and of afforestations) in the IJsselmeerpolders in The Netherlands to assess evolutionary adaptation in Cepaea nemoralis. At 12 localities (three in each polder), I sampled a total of 4390 adult individuals in paired open and shaded habitats, on average 233m apart, and scored these for genetic shell colour polymorphisms. The results show (highly) significant differentiation at most localities, although the genes involved differed per locality. Overall, though, populations in shaded habitats had evolved towards darker shells than those in adjacent open habitats, whereas a 'Cain & Sheppard' diagram (proportion yellow shells plotted against ‘effectively unbanded’ shells) failed to reveal a clear pattern. This... |
Tipo: Article / Letter to the editor |
Palavras-chave: Predation; Crypsis; Contemporary evolution; Gastropoda; Mollusca; Adaptation; 42.73. |
Ano: 2013 |
URL: http://www.repository.naturalis.nl/record/445782 |
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Registros recuperados: 134 | |
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