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11 papers found.
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Fatty acid compositions associated with high-light tolerance in the intertidal rhodophytes Mastocarpus stellatus and Chondrus crispus

The rhodophytes Mastocarpus stellatus and Chondrus crispus occupy the lower intertidal zone of rocky shores along North Atlantic coastlines, with C. crispus generally occurring slightly deeper. Consequently, M. stellatus is exposed to more variable environmental conditions, related to a generally higher stress tolerance of this species. In order to extend our understanding of ...

Habitat modelling of crabeater seals (Lobodon carcinophaga) in the Weddell Sea using the multivariate approach Maxent

The crabeater seal (Lobodon carcinophaga) is the most abundant Antarctic seal and inhabits the circumpolar pack ice zone of the Southern Ocean. Until now, information on important environmental factors affecting its distribution as well as on foraging behaviour is limited. In austral summer 1998, 12 crabeater seals of both sexes and different age classes were equipped with ...

Trophic interactions and life strategies of epi- to bathypelagic calanoid copepods in the tropical Atlantic Ocean

Copepods play central roles in pelagic food webs linking primary production to higher trophic levels. Biomarkers (lipids, stable isotopes) provide modern approaches to study dietary preferences and trophic interactions. A cluster analysis based on the fatty acid (FA) and fatty alcohol compositions of calanoid copepods (copepodids C4/C5 and adult stages) from the southeastern ...

Trophodynamics and life-cycle strategies of the copepods Temora longicornis and Acartia longiremis in the Central Baltic Sea

Trophodynamics and life-cycle strategies of the copepods Temora longicornis and Acartia longiremis in the Baltic Sea were studied, focussing on the seasonal progression of (i) fatty acid (FA) markers in seston and females, (ii) the copepods’ condition as well as (iii) their stage compositions. Trophic marker diversity and high levels of 18:1(n−9) in copepods and seston indicated ...

Distribution and Ecophysiology of Calanoid Copepods in Relation to the Oxygen Minimum Zone in the Eastern Tropical Atlantic

Oxygen minimum zones (OMZs) affect distribution patterns, community structure and metabolic processes of marine organisms. Due to the prominent role of zooplankton, especially copepods, in the marine carbon cycle and the predicted intensification and expansion of OMZs, it is essential to understand the effects of hypoxia on zooplankton distribution and ecophysiology. For this ...

Spatio-Temporal Variability of Copepod Abundance along the 20°S Monitoring Transect in the Northern Benguela Upwelling System from 2005 to 2011

Long-term data sets are essential to understand climate-induced variability in marine ecosystems. This study provides the first comprehensive analysis of longer-term temporal and spatial variations in zooplankton abundance and copepod community structure in the northern Benguela upwelling system from 2005 to 2011. Samples were collected from the upper 200 m along a transect at 20°S ...

Microcopepod community structure in the Gulf of Aqaba and northern Red Sea, with special reference to Oncaeidae

¨ TTGER-SCHNACK DIETRICH SCHNACK WILHELM HAGEN The abundance and vertical distribution of microcopepods sampled by nets with 55 mm mesh size was compared for two neighbouring but hydrographically

Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem

Grote, B., Ekau, W., Stenevik, E. K., Clemmesen, C., Verheye, H. M., Lipinski, M. R., and Hagen, W. 2012. Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem. – ICES Journal of Marine Science, 69: 553–562. Larval mortality in marine fish is strongly linked to ...

Dietary shifts in the copepod Temora longicornis during spring: evidence from stable isotope signatures, fatty acid biomarkers and feeding experiments

EIKE GENTSCH 0 TOBIAS KREIBICH 0 WILHELM HAGEN BARBARA NIEHOFF 0 0 ALFRED WEGENER INSTITUTE FOR POLAR AND MARINE RESEARCH The calanoid copepod Temora longicornis occurs year-round in the southern

Short-term variation of nutritive and metabolic parameters in Temora longicornis females (Crustacea, Copepoda) as a response to diet shift and starvation

Changes in fatty acid patterns, digestive and metabolic enzyme activities and egg production rates (EPR) were studied in the small calanoid copepod Temora longicornis. Female copepods were collected in spring 2005 off Helgoland (North Sea). In the laboratory one group of copepods was fed with the cryptophycean Rhodomonas baltica for a period of 3 days. Another group of copepods was ...

Population dynamics and life strategies of Rhincalanus nasutus (Copepoda) at the onset of the spring bloom in the Gulf of Aqaba (Red Sea)

Abundance, distribution, population structure, lipid content, lipid composition and reproductive and feeding activity of Rhincalanus nasutus were studied in the Gulf of Aqaba and in the northern Red Sea during RV “Meteor”-cruise M 44-2 in February/March 1999. Rhincalanus nasutus occurred in higher numbers in the Gulf of Aqaba (585 ind m−2) than in the northern Red Sea (254 ind ...