Dataset Information

Metabolism and foraging strategies of mid-latitude mesozooplankton during cyanobacterial blooms as revealed by fatty acids, amino acids, and their stable carbon isotopes.

ABSTRACT: Increasing sea surface temperatures (SST) and blooms of lipid-poor, filamentous cyanobacteria can change mesozooplankton metabolism and foraging strategies in marine systems. Lipid shortage and imbalanced diet may challenge the build-up of energy pools of lipids and proteins, and access to essential fatty acids (FAs) and amino acids (AAs) by copepods. The impact of cyanobacterial blooms on individual energy pools was assessed for key species temperate Temora longicornis and boreal Pseudo-/Paracalanus spp. that dominated field mesozooplankton communities isolated by seasonal stratification in the central Baltic Sea during the hot and the cold summer. We looked at (a) total lipid and protein levels, (b) FA trophic markers and AA composition, and (c) compound-specific stable carbon isotopes (?13C) in bulk mesozooplankton and in a subset of parameters in particulate organic matter. Despite lipid-poor cyanobacterial blooms, the key species were largely able to cover both energy pools, yet a tendency of lipid reduction was observed in surface animals. Omni- and carnivory feeding modes, FA trophic makers, and ?13C patterns in essential compounds emphasized that cyanobacterial FAs and AAs have been incorporated into mesozooplankton mainly via feeding on mixo- and heterotrophic (dino-) flagellates and detrital complexes during summer. Foraging for essential highly unsaturated FAs from (dino-) flagellates may have caused night migration of Pseudo-/Paracalanus spp. from the deep subhalocline waters into the upper waters. Only in the hot summer (SST>19.0°C) was T. longicornis submerged in the colder subthermocline water (~4°C). Thus, the continuous warming trend and simultaneous feeding can eventually lead to competition on the preferred diet by key copepod species below the thermocline in stratified systems. A comparison of ?13C patterns of essential AAs in surface mesozooplankton across sub-basins of low and high cyanobacterial biomasses revealed the potential of ?13C-AA isoscapes for studies of commercial fish feeding trails across the Baltic Sea food webs.

SUBMITTER: Eglite E

PROVIDER: S-EPMC6745671 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Metabolism and foraging strategies of mid-latitude mesozooplankton during cyanobacterial blooms as revealed by fatty acids, amino acids, and their stable carbon isotopes.

Eglite Elvita E Graeve Martin M Dutz Jörg J Wodarg Dirk D Liskow Iris I Schulz-Bull Detlef D Loick-Wilde Natalie N

Ecology and evolution 20190816 17

Increasing sea surface temperatures (SST) and blooms of lipid-poor, filamentous cyanobacteria can change mesozooplankton metabolism and foraging strategies in marine systems. Lipid shortage and imbalanced diet may challenge the build-up of energy pools of lipids and proteins, and access to essential fatty acids (FAs) and amino acids (AAs) by copepods. The impact of cyanobacterial blooms on individual energy pools was assessed for key species temperate <i>Temora longicornis</i> and boreal <i>Pseu ...[more]

PMID: 31534704

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Dataset Information

Metabolism and foraging strategies of mid-latitude mesozooplankton during cyanobacterial blooms as revealed by fatty acids, amino acids, and their stable carbon isotopes.

Publications

Metabolism and foraging strategies of mid-latitude mesozooplankton during cyanobacterial blooms as revealed by fatty acids, amino acids, and their stable carbon isotopes.

Similar Datasets

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