Trophodynamics of the hyperiid amphipod Themisto gaudichaudi in the South Georgia region during late austral summer

被引:90
作者
Pakhomov, EA
Perissinotto, R
机构
[1] Southern Ocean Group, Department of Zoology and Entomology, Rhodes University, Grahamstown 6140
关键词
Antarctica; South Georgia; amphipods; Themisto gaudichaudi; feeding; daily ration; predation impact;
D O I
10.3354/meps134091
中图分类号
Q14 [生态学(生物生态学)];
学科分类号
071012 ; 0713 ;
摘要
The feeding dynamics and predation impact of the hyperiid amphipod Themisto gaudichaudi on mesozooplankton were studied in the vicinity of South Georgia, Southern Ocean, during austral summer 1994. Data show that T. gaudichaudi is a visual opportunistic predator, consuming primarily the most abundant species of copepods, euphausiids and pteropods. In situ estimated daily rations were equivalent to 6.3% of body dry weight, and similar to the value of 7.1% of body dry weight derived using an energy budget approach which takes into account the total daily energy requirements. In vitro estimates produced daily rations higher than these, ranging from 8.5 to 21.8% of body dry weight, increasing with prey density. The predation impact of T. gaudichaudi adults, averaged over a 0 to 200 or 0 to 100 m layer, never exceeded 2.1% of mesozooplankton standing stock per day but accounted for up to 70% of the daily secondary production. This suggests that in the vicinity of South Georgia T. gaudichaudi adults are able to control the local mesozooplankton community and may contribute significantly to the downward flux of biogenic carbon.
引用
收藏
页码:91 / 100
页数:10
相关论文
共 44 条
[1]   A SUMMER-WINTER COMPARISON OF ZOOPLANKTON IN THE OCEANIC AREA AROUND SOUTH GEORGIA [J].
ATKINSON, A ;
PECK, JM .
POLAR BIOLOGY, 1988, 8 (06) :463-473
[2]  
BOST CA, 1994, POLAR BIOL, V14, P147
[3]  
CHECHUN IS, 1984, P ZOOL I LENINGRAD, V127, P38
[4]   PROBABLE LOSS OF CHLOROPHYLL-DERIVED PIGMENTS DURING PASSAGE THROUGH THE GUT OF ZOOPLANKTON, AND SOME OF THE CONSEQUENCES [J].
CONOVER, RJ ;
DURVASULA, R ;
ROY, S ;
WANG, R .
LIMNOLOGY AND OCEANOGRAPHY, 1986, 31 (04) :878-887
[5]   THE EFFECT OF TEMPERATURE ON THE GUT CLEARANCE RATE-CONSTANT OF PLANKTONIC COPEPODS [J].
DAM, HG ;
PETERSON, WT .
JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY, 1988, 123 (01) :1-14
[6]   ASPECTS OF SCOTIA SEA ZOOPLANKTON [J].
EVERSON, I ;
WARD, P .
BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, 1980, 14 (01) :93-101
[7]   EXPORT OF BIOGENIC CARBON TO FISH AND TO THE DEEP-OCEAN - THE ROLE OF LARGE PLANKTONIC MICROPHAGES [J].
FORTIER, L ;
LEFEVRE, J ;
LEGENDRE, L .
JOURNAL OF PLANKTON RESEARCH, 1994, 16 (07) :809-839
[8]  
GIBBONS MJ, 1992, S AFR J MARINE SCI, V12, P421
[9]  
Hardy A. C., 1935, Discovery Reports Cambridge, V11, P1
[10]   FOOD WEB OF AN ANTARCTIC MIDWATER ECOSYSTEM [J].
HOPKINS, TL .
MARINE BIOLOGY, 1985, 89 (02) :197-212