Structure and grazing impact of the mesozooplankton community during late summer 1994 near South Georgia, Antarctica

Pakhomov, Evgeny A.; Verheye, Hans M.; Atkinson, Angus; Laubscher, R. K.; Taunton-Clark, J.

doi:10.1007/s003000050175

Cited by 62 publications

(28 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calanoides acutus is one of the most numerically abundant species of copepod in the Southern Ocean (Mackintosh 1934), and a main contributor to the zooplankton biomass of this region (Voronina 1970, Hopkins 1971, Huntley & Escritor 1991, Pakhomov et al 1997. It is primarily herbivorous and, together with other biomass-dominant copepods, may consume up to 55% of daily primary production (Pakhomov et al 1997), so providing a major link between primary production and higher trophic levels.…”

Section: Introductionmentioning

confidence: 99%

“…It is primarily herbivorous and, together with other biomass-dominant copepods, may consume up to 55% of daily primary production (Pakhomov et al 1997), so providing a major link between primary production and higher trophic levels. C. acutus is one of the few true diapausing species in the Southern Ocean, with individuals entering a 7 to 9 mo long diapause, fuelled by extensive lipid reserves of wax ester .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Life-cycle phenotypic composition and mortality of Calanoides acutus (Copepoda: Calanoida) in the Scotia Sea: a modelling approach

Tarling¹,

Shreeve²,

Ward³

et al. 2004

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Life-cycle phenotypic composition and mortality of Calanoides acutus (Copepoda: Calanoida) in the Scotia Sea: a modelling approach

Tarling¹,

Shreeve²,

Ward³

et al. 2004

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

“…4) Perissinotto 1992, and data summarized by Pakhomov et al 1997b). Our deep-water mysid showed R within ranges similar to those of deep-water megabenthic decapod crustaceans (between 0.179 and 0.312: Maynou & Cartes 1998) dwelling at the same environmental temperature (13.1°C), thus supporting the proposal that temperature influences GRT (Elliott & Persson 1978, Chipps 1988, Héroux & Magnan 1996.…”

Section: Discussionmentioning

confidence: 99%

“…It was higher than values reported for Euphausia superba (0.4 to 5% body carbon: Pakhomov et al 1997a), and for the hyperiid Themisto gaudichaudi (6.3% in vivo: ; and within values reported for Euphausia spp. (2.6 to 21.1%: Ponomareva & Kuznetsova 1995 and references therein) and for meso-and macroplankton taxa, including calanoids and euphausiids (0.37 to 56.06: calculated from ingestion rate data given in Pakhomov et al 1997b).…”

Section: Discussionmentioning

confidence: 99%

Trophodynamics of the deep-water suprabenthic mysid Boreomysis arctica in the Catalan Sea (western Mediterranean)

Cartes¹,

Maynou²

2001

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Gut-evacuation rate (R), and daily ration (DR) were studied in the bathyal mysid Boreomysis arctica, a dominant species from the suprabenthic assemblage of the Catalan Sea, during a ca 72 h day-night sampling cycle (Cruise BT1 of March 1994) at depths from 638 to 1256 m. Although the density of B. arctica was higher during daytime in the water column between 0.1 and1.5 m above the sea floor, no significant changes in day-night density were recorded. Feeding peaks were detected during 2 consecutive days in the morning (between 09:59 and 11:58 h), while during the evening and night (between 16:09 and 01:28 h), feeding intensity decreased. The R obtained from field data (R max ) was 0.114 h , respectively. The DR obtained for B. arctica was higher than the range of DR reported for megafaunal deep-sea decapod crustaceans in the same area (between 0.260 and 4.820% dry wt), but fell within the DR range reported for pelagic zooplankton (euphausiids, hyperiids, calanoids). Adopting 0.6 g C m -2 as the mean annual organic carbon consumption of the sediment community from the neigbouring Lacaze-Duthier canyon (north Catalan Sea), B. arctica would consume ca 3.4% of organic carbon annually. Therefore, the trophic impact of this bathyal species is low compared to its numerical dominance in bathyal assemblages, and is often lower than that reported for mesopelagic species.

show abstract

“…The krill daily carbon ration used for this calculation (5%) is not excessive given that their maximum daily ration is probably about 13 to 27% (Clarke et al 1988, Pakhomov et al 1997b). An independent grazing rate can be derived from gross growth rates of 1% of krill mass d -1 measured for northern South Georgia ).…”

Section: Top-down Control On Phytoplanktonmentioning

confidence: 99%

Role of krill versus bottom-up factors in controlling phytoplankton biomass in the northern Antarctic waters of South Georgia

Whitehouse

Atkinson²,

Ward³

et al. 2009

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

The extent to which Antarctic phytoplankton stocks are controlled by 'bottom-up' and/or 'top-down' factors is highly variable. Here we consider data collected at South Georgia during 3 summer surveys that recorded substantial hydrographic variability. A suite of bottom-up and top-down controlling factors were measured simultaneously at the mesoscale. Sea surface temperature varied by > 2°C, macronutrients ranged from near-winter concentrations to near-depleted, while mean densities of a major grazer, krill Euphausia superba, varied between near-zero and > 400 g wet mass m -2 . A general linear model was used to identify the main factors implicated in the observed differences in phytoplankton biomass. Despite east-to-west and on-to off-shelf temperature gradients, temperature per se was not implicated in phytoplankton variability. Also, while there was an abundance of NO 3 -N in surface waters, NH 4 -N was the key nutrient throughout. A domed relationship between phytoplankton and krill peaked between 2 and 4 mg chlorophyll a m -3 and 6 and 30 g krill m -2 . The positive side of this dome was represented by the west off-shelf region downstream of South Georgia. Here, an ample supply of micro-and macronutrients promoted high primary production, and low densities of krill presumably had little grazing effect. This positive relationship between krill and phytoplankton biomasses was interpreted as krill accumulating in areas of good feeding conditions. The negative side of the dome was typified by the east off-shelf region, where macronutrients remained high, primary production rates were low, and krill densities were very high. The grazing rates calculated here suggested that krill affect their food stocks severely, and the negative krill-phytoplankton relationship in this region may reflect locally high krill densities driving down their food supply.

show abstract

Structure and grazing impact of the mesozooplankton community during late summer 1994 near South Georgia, Antarctica

Cited by 62 publications

References 42 publications

Life-cycle phenotypic composition and mortality of Calanoides acutus (Copepoda: Calanoida) in the Scotia Sea: a modelling approach

Life-cycle phenotypic composition and mortality of Calanoides acutus (Copepoda: Calanoida) in the Scotia Sea: a modelling approach

Trophodynamics of the deep-water suprabenthic mysid Boreomysis arctica in the Catalan Sea (western Mediterranean)

Role of krill versus bottom-up factors in controlling phytoplankton biomass in the northern Antarctic waters of South Georgia

Contact Info

Product

Resources

About