Description: The data involves annotations with the MBARI VARS annotation software of pelagic HD video transects obtained by the pelagic in situ observations system PELAGIOS. PELAGIOS is a newly developed towed camera system for deep-sea biological exploration and performance of video transects for diversity and distribution data. The data was collected in 2015 during cruise MSM49 on R/V MARIA S. MERIAN, from 20 to 950 m, during day (187 minutes) and night (292 minutes) transects on the northwestern slope of Senghor Seamount (17°14.2'N, 22°00.7'W; bottom depth of approximately 1000 m). The annotated organisms include fishes, crustaceans and gelatinous zooplankton. One file includes the transect length at each depth at day or night and another file has all individual annotated taxa observed at a particular depth at day or night. The Figure 4 is made with this data. A third file involves the data we used to make Figure 3 which is the comparison between the observations of Poeobius observed in PELAGIOS and UVP5 to calculate sample volume.

Description: During horizontal video transects in the Norwegian Sea pelagic in situ observation system (PELAGIOS), video was collected of the water column and fauna at 4 stations, from 50 m to 1200 m. Fauna were annotated and these annotations are here presented. They include ctenophores, medusae, siphonophores, crustaceans, fishes. The dataset presents diversity, distribution and abundance data. Abundances were estimated based on conversions presented in Hoving et al 2019 (see related to).

Description: Onboard, cephalopods were identified morphologically to the lowest taxonomic level possible (species, genus or family), and whole specimens were preserved in formalin as voucher. In addition, tissue samples of some specimen were collected and preserved in ethanol for barcoding and the genetic reference database used for eDNA metabarcoding.

Description: Net catches of cephalopods were obtained during the cruises POS320/2 (March 2005), MSM49 (November/December 2015) and WH383 (March/April 2015) off Cabo Verde at a total of 18 stations at depths between 0 and 1000 m. Cephalopods were caught during POS320/2 with either a Isaacs-Kidd midwater trawl (IKMT) with a 6 m2 net opening, 4 mm mesh size equipped with a flowmeter, a Hydro-Bios Multinet Maxi with a 0.5 m2 net opening and 500 µm mesh size between the surface and 250 m water depth, or an 80 feet bottom trawl. Net sampling during MSM49 was conducted with two types of multiple opening/closing nets (MOCNESS) and an IKMT. The smaller MOCNESS had a net opening of 1 m2 opening (three nets with a mesh size of 2 mm and six nets with a mesh size of 335 μm) and the larger MOCNESS a net opening of 10 m2 opening (five nets, mesh size: 1.5 mm) and were deployed between the surface to 1000 m. The IKMT had a net opening of 7 m2 and ended in a cod end of 500 µm mesh size. It was deployed to a maximum depth of 500 m. During WH383 a pelagic trawl ('Aalnetz', Engel Netze, Bremerhaven, Germany) with a mouth opening of 16 x 30 m, length of 150 m including multiple opening-closing device, 260 meshes by 180 cm stretched mesh size at the front, a cod end 20 mm stretched mesh-opening and a 1.8 mm inlet sewn into last 1 m of cod end was used with a multisampler (Construction Services AS, Bergen, Norway) allowing depth-stratified sampling. During WH383 three strata (mean vertical extension of ca. 40 m) were trawled mostly during night and one time during daytime at depths between 30 and 700 m in horizontal tows for 30 minutes per stratum with a mean speed of three knots (2.8-3.3 kn). During this cruise, night trawls took place at 22:00 local time, and the day-time trawl at 12:00 local time. Onboard, cephalopods were identified morphologically to the lowest taxonomic level possible (species, genus or family), and whole specimens were preserved in formalin as voucher. In addition, tissue samples of some specimen were collected and preserved in ethanol for barcoding and the genetic reference database used for eDNA metabarcoding. Pelagic video transects with the Pelagic In-Situ Observation System (PELAGIOS, (Hoving et al., 2019a)) were conducted during the cruises MSM49 (Christiansen et al., 2016) (transects between 30 and 1000 m, total towing duration 〉 80h), MSM61 (Fiedler et al., 2020) (transects between 80 and 1200 m, total hours of observations 〉 32h), POS520 (Hoving et al., 2018, p. 520) (transects between 30 and 2500 m, total hours of observations 27h), POS532 (Hoving et al., 2019b) (transects between 30 and 990 m, total hours of observations 19h) and M119 (Brandt, 2016) (transects between 50 and 700 m, total hours of observations 〉 20h) between 2015 and 2019 (Figure 1). PELAGIOS is a battery powered, high-definition camera system that is towed horizontally via a single-wired conductive sea-cable at 0.5 m s -1. Around 0.45 m2 of the water column in front of the camera is illuminated with an LED array. The attached depth sensor and/or a sensor for conductivity, temperature and depth (CTD) with oxygen sensor allows for hydrographic measurements and depth monitoring during transects. Pelagic video transects were conducted between 11-33 minutes per depth, towing the camera horizontally at specified depths. A deep-sea telemetry system allows for transmission of a low-resolution preview of the recorded video. During the cruises POS520 and POS532 the manned submersible JAGO (GEOMAR, Helmholtz Centre for Ocean Research) was used for 30 deployments of about four hours each between the surface and 350 m water depth. During the dives, video was recorded by a high-resolution camera. The videos taken during the PELAGIOS and JAGO dives were annotated manually using the Video Annotation and Reference System (VARS) developed at the Monterey Bay Aquarium Research Institute, which allows annotation and congruent collection of video frames. We also provide raw data on environmental DNA samples taken during POS532 in February 2019 at five stations. The stations off the islands Santo Antão and Fogo were close to the coast (maximum sampled depth 2500 m), CVOO was a reference station in the open ocean (maximum sampled depth 3000 m) and the stations Cyclone and Anticyclone were located eddies that had formed in the wake of Fogo and had propagated southwards (maximum sampled depths 2200 and 600 m, respectively). Per sampled depth, three biological replicates of two liters of seawater each were collected from three different 10 liter Niskin bottles mounted on a CTD rosette. For filtration, 0.22 µm pore size Sterivex-GP filter (Merck Millipore) were directly connected to the Niskin bottle with sterile tubing. The weight of the water in the Niskin bottles was sufficient to filter two liters of seawater per filter. The filters were closed with sterile plastic caps and stored at -80°C until further processing in the laboratory.

Description: Pelagic observations were collected via horizontal video transects using the pelagic in situ observation system PELAGIOS from 50-1000 m during MSM49. The collected video was annotated using the video and annotation reference system (VARS) developed by the Monterey Bay Aquarium Research Institute. In total more than 40 hours of video were collected and annotated, and 43 taxonomic groups were annotated, mostly consisting of gelatinous zooplankton.

Description: We collected optical datasets during horizontal video transects with the Pelagic In Situ Observation System (PELAGIOS), a towed camera system, deployed at different localities in the Fram Strait during the R/V Polarstern expedition PS121 in August/September 2019. This system allowed to collect video footage of the larger-sized pelagic fauna (macro- and megazooplankton) in the water column at 4 stations, at depths ranging from 20 m to 2000m. Gelatinous zooplankton taxa, including ctenophores, cnidarian medusae and siphonophores, were annotated and identified to the lowest taxonomic level possible (species, genus). In this dataset, we present the annotations of these video transects with the associated metadata, and for each annotation, a 4-second videoclip. The name of each video file contains the following information: Observation ID, Expedition, Station, Taxa, Depth (example 1_PS121_HG4_Aglantha_digitale_400.mp4). This dataset was used to assess diversity, distributions and abundance data on gelatinous zooplankton in the rapidly changing Atlantic-Arctic gateway, Fram Strait.

Description: We collected optical datasets during horizontal video transects with the Pelagic In Situ Observation System (PELAGIOS), a towed camera system, deployed at different localities in the Fram Strait during the R/V Polarstern expedition PS126 from May to June 2021. This system allowed to collect video footage of the larger-sized pelagic fauna (macro- and megazooplankton) in the water column at 3 stations, at depths ranging from 20 m to 2000m. Gelatinous zooplankton taxa, including ctenophores, cnidarian medusae and siphonophores, were annotated and identified to the lowest taxonomic level possible (species, genus). In this dataset, we present the annotations of these video transects with the associated metadata, and for each annotation, a 4-second videoclip. The name of each video file contains the following information: Observation ID, Expedition, Station, Taxa, Depth (example 1_PS126_HG4_Aglantha_digitale_400.mp4). This dataset was used to assess diversity, distributions and abundance data on gelatinous zooplankton in the rapidly changing Atlantic-Arctic gateway, Fram Strait.

Description: Pelagic observations were collected via horizontal video transects using the pelagic in situ observation system PELAGIOS from 50-1000 m during MSM49. The collected video was annotated using the video and annotation reference system (VARS) developed by the Monterey Bay Aquarium Research Institute. In total more than 40 hours of video were collected and annotated, and 43 taxonomic groups were annotated, mostly consisting of gelatinous zooplankton. The data consists of counts of taxonomic groups (〉1 cm) linked to location and depth in the Cape Verde region. These counts are converted to abundance data (ind./m3).