The relationship between biodiversity and ecosystem functioning is a central issue in ecology. Previous studies have shown that producer diversity can impact the consumer community via predator-prey interactions. However, direct observations of this relationship remain rare, in particular for aquatic ecosystems. In this research, the relationship between phytoplankton diversity (species richnes...

Phytol-U-(14)C was adsorbed on algae and ingested in this form by zooplanktonic copepods (two species of Calanus). The lipids of these animals were analyzed after 48 hr and found to contain radioactive pristane and radioactive phytanic acid. The conversion of phytol to pristane by the copepods is interpreted as a likely biological source of pristane in nature.

In contrast to higher metazoans such as copepods and fish, ctenophores are a basal metazoan lineage possessing a relatively narrow set of sensory-motor capabilities. Yet lobate ctenophores can capture prey at rates comparable to sophisticated predatory copepods and fish, and they are capable of altering the composition of coastal planktonic communities. Here, we demonstrate that the predatory s...

We examined the influence of macronutrient (nitrate and phosphate) additions on Ni uptake by phytoplankton (Prorocentrum donghaiense and Skeletonema costatum) and its subsequent transfer to marine copepods (Calanus sinicus and Labidocera euchaeta). Ni uptake by phytoplankton after 24h of exposure was markedly dependent on nutrient conditions, with a higher nutrient quota facilitating Ni accumul...

Fluorogenic assays for a set of five hydrolytic enzymes involved in digestion and food utilization (alanine and arginine aminopeptidase, lipase/esterase, chitobiase, and beta-glucosidase) were optimized to measure activities of these enzymes in the same extracts of individual small North Sea copepods. The enzyme activities of Acartia clausi, Centropages typicus, Corycaeus anglicus, Paracalanus ...

The critical role played by copepods in ocean ecology and biogeochemistry warrants an understanding of how these animals may respond to ocean acidification (OA). Whilst an appreciation of the potential direct effects of OA, due to elevated pCO2, on copepods is improving, little is known about the indirect impacts acting via bottom-up (food quality) effects. We assessed, for the first time, the ...

The carbon (C), nitrogen (N) and phosphorus (P) contents (% of dry weight) of some crustacean zooplankton were studied in the Baltic Sea. The copepod Acartia sp. had a stable C and N content (48.3 ± 0.8% C, 12.4 ± 0.2% N, C:N ratio 4.5 ± 0.1). The P content was variable (1–2%), probably depending on developmental stage and season. Copepods accumulating fat, like Pseudocalanus minutus elongatus,...

More than 2,500 species of copepods (Class Maxillopoda; Subclass Copepoda) occur in the marine planktonic environment. The exceptional morphological conservation of the group, with numerous sibling species groups, makes the identification of species challenging, even for expert taxonomists. Molecular approaches to species identification have allowed rapid detection, discrimination, and identifi...

Interannual copepod abundance (number m ) and sea surface temperatures (SST, 2-m depth) were examined from four stations in Icy Strait, southeastern Alaska, monthly from May to September, 1997e2002. SST was generally lowest in May (y7(C), increased rapidly to a summer peak (y12(C), and declined again by September. SST was relatively high in the El Niño year, 1998, and was low during a regional ...

Marine snow aggregates are colonized by copepods, and encounter rates inferred from observed abundances of colonizers are high. We examined the potential for hydromechanical and chemical remote detection. The fluid disturbance generated by a sinking aggregate was described by solving the Navier-Stokes’ equation for a sinking sphere at Reynolds numbers typical of marine snow (up to 20). Fluid de...