Macrozooplankton and nekton were collected with a Rectangular Midwater Trawl 25 (RMT25) over several visits to the sustained observation location P3 (52.70 S, 40.26 W) in the northern Scotia Sea during November and December 2017. The work was carried out as part of the NERC Large Grant, COMICS (Controls on Mesopelagic Interior Carbon) on board the RRS Discovery (cruise DY086). The RMT25 net hauls sampled between 10 and 500 m depth, with the water column divided into 2 depth intervals (10-250 m and 250-500 m). A total of 6 hauls were obtained during 3 separate visits to station P3, each visit comprising a pair of hauls, of which one was carried out in nominal daytime and the other in nominal nighttime. Catches were immediately sorted on board and identified to the lowest taxonomic level feasible. Subsamples of the catches were retained, principally for subsequent biochemical and physiological analyses. In total, 777 fish were caught, belonging to at least 23 species, with catches dominated by the myctophids Krefftichthys anderssoni, Gymnoscopelus braueri, Electrona antarctica and Protomyctophum tenesoni. The water column below 250m was dominated by Bathylagus spp. Temperate myctophid species, such as Protomyctophum parallelum and Protomyctophum andreyeshevi were also caught in small numbers. With regards macrozooplankton, the 250m-500m depth interval was dominated by the jellyfish, Atolla and Periphylla. The tunicate Salpa thompsoni and the euphausiids Euphausia triacantha and Thysanoessa spp. were also relatively abundant. Jellyfish still dominated catches in shallower waters (250m-10m), closely followed by euphausiids and Salpa thompsoni and chaetognaths. Themisto gaudichaudii and Parandania boecki were the most numerous amphipod species caught. Decapods were only caught in the deeper depth interval, both day and night.

Macrozooplankton and nekton were collected with a Rectangular Midwater Trawl 25 (RMT25) at locations within the Benguela Current region in May and June 2018. The work was carried out as part of the NERC Large Grant, COMICS (Controls on Mesopelagic Interior Carbon) on board the RRS Discovery (cruise DY090). Depth-discrete samples were collected across four time stations (BS1, BN1-3) between 0-750 m at intervals of 750-500m, 500-250m, 250-125m and 125-10 m. At each time station, two RMT25 hauls were deployed in the hours of darkness and two in daylight, with 16 deployments being undertaken overall. The RMT25 was operated via a downwire net monitor and was equipped with a flow meter, and temperature and salinity sensors. Nets in the deep strata (750-500m and 500-250m) were sampled for approximately 40 mins. and nets in the shallow strata (250-125m, 125-10m) for approximately 20mins. Catches were immediately sorted on board and identified to the lowest taxonomic level feasible. All fishes and subsamples of the other parts of the catch were retained (frozen), principally for subsequent biochemical and physiological analyses. In total, 1917 fish were caught and preserved (not including Cyclothone spp.). Catches were dominated by the myctophids and various other mesopelagic fish species. The water column below 250m was dominated by Bathylagus spp. and genus Melamphidae spp. The most numerous fish overall were the Cyclothone spp. which occurred in large numbers below 500m. In deeper depth intervals (250m-750m), the macrozooplankton component of the RMT25 net catches was mostly dominated by Decapoda and hydromedusae of the genus Atolla spp.. Salps, smaller hydromedusa species and small euphausiids Euphausia hanseni and Nematocelis megalops dominated the shallower depths (10-250m).

Mesozooplankton were collected with a MOCNESS net system during the oceanographic cruise JR16003 (Dec 2016 to Jan 2017). The MOCNESS comprised 9 separate nets which opened in sequence such that the closing of one net opened the next; net 1 was open during the descent of the net to its maximum depth (1000 m) while the remaining 8 depths opened at regular intervals during the reascent to the surface. All catches were immediately preserved in 4% buffered formaldehyde. Identification of taxa was performed by the Morski Institute (Poland). Specimens were categorised to the lowest possible taxonomic level, which, in some cases, encompassed developmental stages but, in other cases, was limited to higher order taxa. Each taxa was enumerated to determine abundance in units of individuals m-3. The dataset allows examination of the distribution and abundance of these species across Polar Frontal Zone in Southern Ocean Atlantic sector. The survey was funded by The UK Natural Environment Research Council (NERC) and carried out as part of the POETS Wester Core Box and SCOOBIES programmes at British Antarctic Survey. The time of Geraint Tarling and the analysis of the MOCNESS nets was funded by the NERC grant "SeaDNA - Assessing marine biodiversity and structure using environmental DNA: from groundtruthing to food web structure and stability" NE/N00616X/1 PI: Stefano Mariani.

Aerial survey of St Andrews Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_12 which was carried out on 2024-10-20. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of Hound Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_15 which was carried out on 2024-10-21. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of St Andrews Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_16 which was carried out on 2024-01-21. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of St Andrews Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_17 which was carried out on 2024-10-22. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of St Andrews Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_19 which was carried out on 2024-10-25. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of Hound Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_20 which was carried out on 2024-10-25. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).

Aerial survey of St Andrews Bay elephant seal colony, Mirounga leonina, during the 2023/24 season conducted using a remotely piloted aerial system (RPAS). The aerial survey was conducted as part of the Darwin Plus (DPLUS) 214 project: Southwest Atlantic Elephant Seal Population Assessment (SAESPA). Dataset includes the original images and log files, the original RINEX GNSS (global navigation satellite system) base station files, the post-processed global navigation satellite system and imagery data, along with the resulting georeferenced DSM (digital surface model) and an orthorectified mosaic of the imagery. This dataset is from flight number DPLUS_214_21 which was carried out on 2024-10-26. This work was supported by the Overseas Territories Environment and Climate Fund under Grant Darwin Plus ref: DPLUS214: Southwest Atlantic Elephant Seal Population Assessment (SAESPA).