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: 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.

Description: Fundamental insight on predator-prey dynamics in the deep sea is hampered by a lack of combined data on hunting behavior and prey spectra. Deep-sea niche segregation may evolve when predators target specific prey communities, but this hypothesis remains untested. We combined environmental DNA (eDNA) metabarcoding with biologging to assess cephalopod community composition in the deep-sea foraging habitat of two top predator cetaceans. Here, we are presenting the eDNA data from seawater samples obtained during a cruise on RV Pelagia in 2018 off Terceira, Azores, sampled directly in the foraging habitats of two cetacean top-predators from the surface to 1600 m. The water was collected using Niskin bottles mounted on a CTD rosette at seven or eight depths in biological triplicates and filtered on sterile Sterivex filter. After DNA extraction and PCR amplification with two universal cephalopod primer (Ceph18S, targeting the nuclear 18S rRNA gene and CephMLS targeting the mitochondrial 16S rRNA gene), the samples were sequenced on an Illumina MiSeq with the MiSeq Reagent kit v3 (600 cycles).

Description: 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: Cephalopods are pivotal components of marine food webs, but biodiversity studies are hampered by challenges to sample these agile marine molluscs. Metabarcoding of environmental DNA (eDNA) is a potentially powerful technique to study oceanic cephalopod biodiversity and distribution but has not been applied thus far. We present a novel universal primer pair for metabarcoding cephalopods from eDNA, Ceph18S (Forward: 5′-CGC GGC GCT ACA TAT TAG AC-3′, Reverse: 5′-GCA CTT AAC CGA CCG TCG AC-3′). The primer pair targets the hypervariable region V2 of the nuclear 18S rRNA gene and amplifies a relatively short target sequence of approximately 200 bp in order to allow the amplification of degraded DNA. In silico tests on a reference database and empirical tests on DNA extracts from cephalopod tissue estimate that 44-66% of cephalopod species, corresponding to about 310-460 species, can be amplified and identified with this primer pair. A multi-marker approach with the novel Ceph18S and two previously published cephalopod mitochondrial 16S rRNA primer sets targeting the same region (Jarman et al. 2006 Mol. Ecol. Notes. 6, 268-271; Peters et al. 2015 Mar. Ecol. 36, 1428-1439) is estimated to amplify and identify 89% of all cephalopod species, of which an estimated 19% can only be identified by Ceph18S. All sequences obtained with Ceph18S were submitted to GenBank, resulting in new 18S rRNA sequences for 13 cephalopod taxa

Description: Significance: A central goal in invasion genomics is to identify and determine the mechanisms that underlie the successful colonization, establishment, and subsequent range expansion of invasive populations of nonindigenous species. Using a whole-genome approach, we evaluate the importance of genetic diversity for the successful establishment of nonindigenous species. Our study shows that genetic diversity per se is not the major factor driving invasions, since we observed all possible scenarios with invasive populations showing reduced, similar but also increased, genetic diversity relative to the native population. Using coalescent methods, we reconstruct the demographic history of the invasion and infer the source population of each invasion event, which shows that propagule pressure and multiple introductions play an important role in determining invasion success. Abstract: Invasion rates have increased in the past 100 y irrespective of international conventions. What characterizes a successful invasion event? And how does genetic diversity translate into invasion success? Employing a whole-genome perspective using one of the most successful marine invasive species world-wide as a model, we resolve temporal invasion dynamics during independent invasion events in Eurasia. We reveal complex regionally independent invasion histories including cases of recurrent translocations, time-limited translocations, and stepping-stone range expansions with severe bottlenecks within the same species. Irrespective of these different invasion dynamics, which lead to contrasting patterns of genetic diversity, all nonindigenous populations are similarly successful. This illustrates that genetic diversity, per se, is not necessarily the driving force behind invasion success. Other factors such as propagule pressure and repeated introductions are an important contribution to facilitate successful invasions. This calls into question the dominant paradigm of the genetic paradox of invasions, i.e., the successful establishment of nonindigenous populations with low levels of genetic diversity.

Description: Carbon sequestration and storage in mangroves, salt marshes and seagrass meadows is an essential coastal ‘blue carbon’ ecosystem service for climate change mitigation. Here we offer a comprehensive, global and spatially explicit economic assessment of carbon sequestration and storage in three coastal ecosystem types at the global and national levels. We propose a new approach based on the country-specific social cost of carbon that allows us to calculate each country’s contribution to, and redistribution of, global blue carbon wealth. Globally, coastal ecosystems contribute a mean ± s.e.m. of US$190.67 ± 30 bn yr−1 to blue carbon wealth. The three countries generating the largest positive net blue wealth contribution for other countries are Australia, Indonesia and Cuba, with Australia alone generating a positive net benefit of US$22.8 ± 3.8 bn yr−1 for the rest of the world through coastal ecosystem carbon sequestration and storage in its territory.

Description: The deep sea is among the largest, most biologically diverse, yet least-explored ecosystems on Earth. Baseline information on deep-sea biodiversity is crucial for understanding ecosystem functioning and for detecting community changes. Here, we established a baseline of cephalopod community composition and distribution off Cabo Verde, an archipelago in the eastern tropical Atlantic. This baseline served to test the hypothesis that Cabo Verde is biogeographically separated from other Macaronesian archipelagos and allowed the identification of cephalopod species which may play a role in the Macaronesian carbon cycle and oceanic food web. To investigate cephalopod community composition, this study used 746 individual cephalopods obtained by nets (0–1000 m) and 52 cephalopod encounters during video surveys with either towed camera (0–2500 m) or manned submersible (0–375 m). Additionally, environmental DNA (eDNA) metabarcoding on 105 seawater samples (50–2500 m), using an 18S rRNA universal cephalopod primer pair, and a species-specific primer pair for Taningia danae resulted in the detection of 32 cephalopod taxa. When combined, the three methods detected a total of 87 taxa, including 47 distinct species. Each method contributed between 7 and 54% of taxa that were not detected by the other methods, indicating that multiple methodological approaches are needed for optimal deep-sea cephalopod biodiversity assessments. This study documents the occurrences of six species and three genera for the first time in waters surrounding Cabo Verde. Video surveys and eDNA analysis detected Taningia danae recurrently (100–2500 m). eDNA metabarcoding proved to be a powerful tool for cephalopod biodiversity monitoring and complementary to traditional sampling methods. When also including literature records, Cabo Verde hosts at least 102 cephalopod taxa including 30 families and 64 benthic and pelagic species. The total number and species composition of Cabo Verde cephalopods is similar to the Canary Islands and Azores, two known cephalopod biodiversity hotspots, but the Cabo Verde octopus fauna seems to differ. Due to a range of life history characteristics, we hypothesize that the squids Taningia danae (Octopoteuthidae) and Sthenoteuthis pteropus (Ommastrephidae) are important in the carbon cycle of Macaronesia. As a cephalopod biodiversity hotspot Cabo Verde could function as a model region to investigate cephalopod biology and ecology in a rapidly changing Atlantic Ocean.

Description: Coastal oceans are particularly affected by rapid and extreme environmental changes with dramatic consequences for the entire ecosystem. Seagrasses are key ecosystem engineering or foundation species supporting diverse and productive ecosystems along the coastline that are particularly susceptible to fast environmental changes. In this context, the analysis of phenotypic plasticity could reveal important insights into seagrasses persistence, as it represents an individual property that allows species’ phenotypes to accommodate and react to fast environmental changes and stress. Many studies have provided different definitions of plasticity and related processes (acclimation and adaptation) resulting in a variety of associated terminology. Here, we review different ways to define phenotypic plasticity with particular reference to seagrass responses to single and multiple stressors. We relate plasticity to the shape of reaction norms, resulting from genotype by environment interactions, and examine its role in the presence of environmental shifts. The potential role of genetic and epigenetic changes in underlying seagrasses plasticity in face of environmental changes is also discussed. Different approaches aimed to assess local acclimation and adaptation in seagrasses are explored, explaining strengths and weaknesses based on the main results obtained from the most recent literature. We conclude that the implemented experimental approaches, whether performed with controlled or field experiments, provide new insights to explore the basis of plasticity in seagrasses. However, an improvement of molecular analysis and the application of multi‐factorial experiments are required to better explore genetic and epigenetic adjustments to rapid environmental shifts. These considerations revealed the potential for selecting the best phenotypes to promote assisted evolution with fundamental implications on restoration and preservation efforts.