• Energy Research

Biomass (mg dry mass m-3) of zooplankton taxa was calculated from samples of Polarstern cruise PS78 (ARK-XXVI/1) on a transect across Fram Strait. Individual dry mass was calculated converting wet mass (biovolume) to dry mass for Arctic mesozooplankton taxa. The conversion factors for specific taxa are listed in Cornils et al. 2022 (Table 3). Samples were taken with the Multinet midi (Hydrobios, Kiel), which is equipped with five nets (mesh size: 150 µm). Samples were analysed via image-based ZooScan analyses. The classified images are available at the web application EcoTaxa: https://ecotaxa.obs-vlfr.fr/prj/2771

Dry mass (mg DM m-3) of zooplankton bulk samples was measured from samples of Polarstern cruise PS106 (SIPKA). Samples were taken with the RMT1 net with a mesh size of 320 µm. Each sample was fractionated onboard into the following size classes: 0 – 0.5 mm, 0.5 – 1 mm, 1 – 2 mm, 2 – 4 mm and >4 mm) and frozen in petri dishes at -20°C for dry mass measurements. Each size fraction was freeze-dried for 48 hours and subsequently the dry mass was weighed to the nearest microgram.

Abundance (ind. m-3) of zooplankton taxa was calculated from samples of Polarstern cruise PS78 (ARK-XXVI/1) on a transect across Fram Strait. Samples were taken with the Multinet midi (Hydrobios, Kiel), which is equipped with five nets (mesh size: 150 µm). Samples were analysed via microscopic analyses for comparison with image-based analysis.

Drymass (mg DM m-3) of zooplankton taxa was calculated using conversion factors from biovolume to dry mass as described in Cornils et al. (2022) from samples of Polarstern cruise PS106 (SIPKA). Samples were taken with the RMT1 net with a mesh size of 320 µm. . Prior to the analysis each sample was fractionated into the following size classes: 0 – 0.5 mm, 0.5 – 1 mm, 1 – 2 mm, 2 – 4 mm and >4 mm). Samples were analysed via image-based ZooScan analysis. The classified images are available at the web application EcoTaxa: https://ecotaxa.obs-vlfr.fr/prj/2534.

Mesozooplankton samples were collected with the Multinet midi (Hydrobios, Kiel) and Bongo nets during the POLARSTERN cruise PS78 (ARK-XXVI/1) on a transect across Fram Strait. The samples were analyzed with imaged-based ZooScan analysis (Gorsky et al. 2010) and microscopic counts to compare the taxonomic resolution and abundance of both methods as described in Cornils et al. (2022). The data collection includes abundance, biovolume, biomass and length measurements derived from the image-based analysis with ZooScan as well as abundances based on microscopic counts. To compare biomass estimates from image parameters direct measurements of prosome length and individual dry mass of Calanus spp. are also provided. The data analysis is described in Cornils et al. (2022).The R scripts deposited at GitHub (Cornils 2022) allow the transformation of the EcoTaxa image dataset https://ecotaxa.obs-vlfr.fr/prj/2771 to abundance, biovolume and dry mass of the zooplankton organisms.

This dataset contains energy content measurements performed on zooplankton collected in the Arctic Ocean during the MOSAiC expedition (PS122) from November 2019 untill September 2020. Energy content measurements were done on Apherusa glacialis, Themisto abyssorum, Chaetognatha, Thysanoessa longicaudata and Calanus hyperboreus. These species are all known prey of polar cod (Boreogadus saida), and their energy content was measured to be included in a bioenergetic model of the growth rate of this predator and to gain insight in the differences between prey species. The meaurements were performed on freeze-dried specimens using a 6725 semi-micro oxygen calorimeter (Parr, USA) connected to a 6772 calorimetric thermometer (Parr, USA). All individual Calanus hyperboreus used for measurements were adult females.

Abundances (ind. m-3) of zooplankton taxa were calculated from samples of Polarstern cruise PS78 (ARK-XXVI/1) on a transect across Fram Strait. Samples were taken with the Multinet midi (Hydrobios, Kiel), equipped with five nets (mesh size: 150 µm). To evaluate the relationships between equivalent spherical diameter (ESD) and prosome length for copepods or total length for other zooplankton 2725 images were randomly selected and measured across all zooplankton taxa. Samples were analysed via image-based ZooScan analyses. The classified images are available at the web application EcoTaxa: https://ecotaxa.obs-vlfr.fr/prj/2771

This dataset contains energy content measurements performed on zooplankton collected in the Arctic Ocean during the MOSAiC expedition (PS122) from November 2019 untill September 2020. Energy content measurements were done on Apherusa glacialis, Themisto abyssorum, Chaetognatha, Thysanoessa longicaudata and Calanus hyperboreus. These species are all known prey of polar cod (Boreogadus saida), and their energy content was measured to be included in a bioenergetic model of the growth rate of this predator and to gain insight in the differences between prey species. The meaurements were performed on freeze-dried specimens using a 6725 semi-micro oxygen calorimeter (Parr, USA) connected to a 6772 calorimetric thermometer (Parr, USA).