The Ecology of the Ctenophore Pleurobrachia Pileus in Scottish Waters

Fraser, J. H.

doi:10.1093/icesjms/33.2.149

Cited by 76 publications

(39 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We conclude that if density-dependent competition for food was actually responsible for the development of an Ideal Free Distribution in fish postlarvae, this competition was generated at the level of the entire predator assemblage (including fish postlarvae) rather than at the intra-or interspecific level among fish postlarvae. This supports the hypothesis that the dynamics of invertebrate predators could play a central role in the density-dependent regulation of marine fish numbers during the larval and postlarval phase (Fraser 1970, Frank 1986.…”

Section: Other Hypothesessupporting

confidence: 87%

See 1 more Smart Citation

Optimal foraging and density-dependent competition in marine fish larvae

Fortier¹,

Harris²

1989

Mar. Ecol. Prog. Ser.

113

View full text Add to dashboard Cite

ABSTRACT. Ontogenetic migrations of fish larvae were studied in relation to vertical distribution of their prey and their predators at a single, unstratified, 60 m deep, station off Plymouth, UK. The vertical distribution of fish larvae was highly stratified. Die1 migrations were weak. Marked ontogenetic migrations reflected a size-related shlft in the equilibrium between predation and starvation risks. Yolksac larvae concentrated in the top half of the water column where planktonic predators were the least abundant. As size increased, the overlap between the vertical distribution of the postlarvae and that of potential predators increased. Postlarval stages of species feeding on copepods were distributed in direct proportion to resource availability. This suggested an optimization of postlarval foraging behaviour in response to density-dependent competition for food. Calculations showed that the larvae themselves had little impact on their resource, but indications were found that the abundance of larval fish food was affected by other planktivorous predators. We conclude that the density-dependent competition for food suggested by the observed patterns of postlarval distribution could only be generated at the level of the entire assemblage of planktonic predators.

show abstract

Section: Other Hypothesessupporting

confidence: 87%

“…Studies have shown that invertebrate predators can be significant competitors of fish larvae feeding on copepods (e.g. Fraser 1970, Williams & Collins 1985, Frank 1986). Copepod eggs and nauplii comprised 55 % of the prey exploited by fish larvae.…”

Section: Other Hypothesesmentioning

confidence: 99%

Optimal foraging and density-dependent competition in marine fish larvae

Fortier¹,

Harris²

1989

Mar. Ecol. Prog. Ser.

113

View full text Add to dashboard Cite

show abstract

“…The source of the seed population of ctenophores is a n unresolved question in many areas, but the species is often assumed to overwinter in the water column in small numbers (Bigelow 1926, Fraser 1970. In the present study, the total volumes filtered durlng the first 3 cruises (February, March and Aprll) were 5700, 7000, and 8600 m3, respectively (average 664 m3 per station).…”

Section: Seasonal Variations Of Ctenophoresmentioning

confidence: 53%

Distributional and seasonal patterns of ctenophores in Malangen, northern Norway

Falkenhaug¹

1996

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Annual cycles of abundance of the ctenophore species Bolinopsis ~nfundibulum and Beroe cucumls wel-e studied in the Malangen fjord, northern Norway, during 1992. The seasonal dynamics were characterized by alternating abundances of the 2 species A biomass increase of B infundibulum occurl-ed in April and May, I-eaching a peak of 2 to 7 m1 m-.' wet volume in the surface layers in summer. The specles started to reproduce in the inner part of the fjord, and then propagated throughout the entire fjord system. Length frequency distributions indicated that B. infundibulum were reproducing continuously d u n n g the summer months. Biovolumes of B. infundibulum decreased in August, leaving a small number of individuals (

show abstract

“…When the population builds up through intense reproduction in spring, the average size of the individuals decreases, to reach a minimum around August (Greve 1971), and main reproduction is early in the season. Even though Pleurobrachia individuals are often also found in deeper water layers during the period of maximum densities (but see Kopacz 1994), several authors have observed that one of the additional reasons why Pleurobrachia are rarely found in the water column in winter is that they are still closer to the sediment (Fraser 1970;van der Veer and Sadee 1984). The reasons for this behaviour in winter are unknown, possibly it is an energy-saving strategy when densities of pelagic prey items are so low that finding sufficient food in the water column is not possible, which could be the case in winter.…”

Section: Introductionmentioning

confidence: 99%

Effects of temperature and the presence of benthic predators on the vertical distribution of the ctenophore Pleurobrachia pileus

2004

View full text Add to dashboard Cite

This study details the investigations of the effect of temperature and the presence of predators on the vertical distribution of the ctenophore Pleurobrachia pileus. Previous studies had suggested that P. pileus moves to the sediment when exposed to colder temperatures as an energy saving strategy. Although we did observe an effect of temperature on the movement of the ciliate combs, the effect of temperature on the average depth of animals in the water column was not significant, but a significant interaction was found between temperature and exposure time. In the presence of benthic predators or of water previously inhabited by these predators P. pileus changed its vertical distribution significantly, and moved away from the sediment, thus reducing the risk of being predated. We conclude that P. pileus can sense the presence of its predators, and changes its behaviour accordingly.

show abstract

The Ecology of the Ctenophore Pleurobrachia Pileus in Scottish Waters

Cited by 76 publications

References 0 publications

Optimal foraging and density-dependent competition in marine fish larvae

Optimal foraging and density-dependent competition in marine fish larvae

Distributional and seasonal patterns of ctenophores in Malangen, northern Norway

Effects of temperature and the presence of benthic predators on the vertical distribution of the ctenophore Pleurobrachia pileus

Contact Info

Product

Resources

About