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The Norway lobster, Nephrops norvegicus, supports a key European fishery. Stock assessments for this species are mostly based on trawling and UnderWater TeleVision (UWTV) surveys. However, N. norvegicus are burrowing organisms and these survey methods are unable to sample or observe individuals in their burrows. To account for this, UWTV surveys generally assume that “1 burrow system = 1 animal”, due to the territorial behavior of N. norvegicus. Nevertheless, this assumption still requires in-situ validation. Here, we outline how to improve the accuracy of current stock assessments for N. norvegicus with novel ecological monitoring technologies, including: robotic fixed and mobile camera-platforms, telemetry, environmental DNA (eDNA), and Artificial Intelligence (AI). First, we outline the present status and threat for overexploitation in N. norvegicus stocks. Then, we discuss how the burrowing behavior of N. norvegicus biases current stock assessment methods. We propose that state-of-the-art stationary and mobile robotic platforms endowed with innovative sensors and complemented with AI tools could be used to count both animals and burrows systems in-situ, as well as to provide key insights into burrowing behavior. Next, we illustrate how multiparametric monitoring can be incorporated into assessments of physiology and burrowing behavior. Finally, we develop a flowchart for the appropriate treatment of multiparametric biological and environmental data required to improve current stock assessment methods.

Thriving benthic communities were observed in the oxygen minimum zones along the southwestern African margin. On the Namibian margin, fossil cold-water coral mounds were overgrown by sponges and bryozoans, while the Angolan margin was characterized by cold-water coral mounds covered by a living coral reef. To explore why benthic communities differ in both areas, present-day environmental conditions were assessed, using conductivity–temperature–depth (CTD) transects and bottom landers to investigate spatial and temporal variations of environmental properties. Near-bottom measurements recorded low dissolved oxygen concentrations on the Namibian margin of 0–0.15 mL L−1 (≜0 %–9 % saturation) and on the Angolan margin of 0.5–1.5 mL L−1 (≜7 %–18 % saturation), which were associated with relatively high temperatures (11.8–13.2 ∘C and 6.4–12.6 ∘C, respectively). Semidiurnal barotropic tides were found to interact with the margin topography producing internal waves. These tidal movements deliver water with more suitable characteristics to the benthic communities from below and above the zone of low oxygen. Concurrently, the delivery of a high quantity and quality of organic matter was observed, being an important food source for the benthic fauna. On the Namibian margin, organic matter originated directly from the surface productive zone, whereas on the Angolan margin the geochemical signature of organic matter suggested an additional mechanism of food supply. A nepheloid layer observed above the cold-water corals may constitute a reservoir of organic matter, facilitating a constant supply of food particles by tidal mixing. Our data suggest that the benthic fauna on the Namibian margin, as well as the cold-water coral communities on the Angolan margin, may compensate for unfavorable conditions of low oxygen levels and high temperatures with enhanced availability of food, while anoxic conditions on the Namibian margin are at present a limiting factor for

Thriving benthic communities were observed in the oxygen minimum zones along the southwestern African margin. On the Namibian margin, fossil cold-water coral mounds were overgrown by sponges and bryozoans, while the Angolan margin was characterized by cold-water coral mounds covered by a living coral reef. To explore why benthic communities differ in both areas, present-day environmental conditions were assessed, using conductivity–temperature–depth (CTD) transects and bottom landers to investigate spatial and temporal variations of environmental properties. Near-bottom measurements recorded low dissolved oxygen concentrations on the Namibian margin of 0–0.15 mL L−1 (≜0 %–9 % saturation) and on the Angolan margin of 0.5–1.5 mL L−1 (≜7 %–18 % saturation), which were associated with relatively high temperatures (11.8–13.2 ∘C and 6.4–12.6 ∘C, respectively). Semidiurnal barotropic tides were found to interact with the margin topography producing internal waves. These tidal movements deliver water with more suitable characteristics to the benthic communities from below and above the zone of low oxygen. Concurrently, the delivery of a high quantity and quality of organic matter was observed, being an important food source for the benthic fauna. On the Namibian margin, organic matter originated directly from the surface productive zone, whereas on the Angolan margin the geochemical signature of organic matter suggested an additional mechanism of food supply. A nepheloid layer observed above the cold-water corals may constitute a reservoir of organic matter, facilitating a constant supply of food particles by tidal mixing. Our data suggest that the benthic fauna on the Namibian margin, as well as the cold-water coral communities on the Angolan margin, may compensate for unfavorable conditions of low oxygen levels and high temperatures with enhanced availability of food, while anoxic conditions on the Namibian margin are at present a limiting factor for

The Cretaceous period (~145–65 m.y. ago) was characterized by intervals of enhanced organiccarbon burial associated with increased primary production under greenhouse conditions.The global consequences of these perturbations, oceanic anoxic events (OAEs), lasted upto 1 m.y., but short-term nutrient and climatic controls on widespread anoxia are poorly understood.Here, we present a high-resolution reconstruction of oceanic redox and nutrient cyclingas recorded in subtropical shelf sediments from Tarfaya, Morocco, spanning the initiation ofOAE2. Iron-sulfur systematics and biomarker evidence demonstrate previously undescribedredox cyclicity on orbital time scales, from sulfidic to anoxic ferruginous (Fe-rich) water-columnconditions. Bulk geochemical data and sulfur isotope modeling suggest that ferruginousconditions were not a consequence of nutrient or sulfate limitation, despite overall low sulfateconcentrations in the proto–North Atlantic. Instead, fluctuations in the weathering influxes ofsulfur and reactive iron, linked to a dynamic hydrological cycle, likely drove the redox cyclicity.Despite the potential for elevated phosphorus burial in association with Fe oxides underferruginous conditions on the Tarfaya shelf, porewater sulfide generation drove extensive phosphorusrecycling back to the water column, thus maintaining widespread open-ocean anoxia.

The Cretaceous period (~145–65 m.y. ago) was characterized by intervals of enhanced organiccarbon burial associated with increased primary production under greenhouse conditions.The global consequences of these perturbations, oceanic anoxic events (OAEs), lasted upto 1 m.y., but short-term nutrient and climatic controls on widespread anoxia are poorly understood.Here, we present a high-resolution reconstruction of oceanic redox and nutrient cyclingas recorded in subtropical shelf sediments from Tarfaya, Morocco, spanning the initiation ofOAE2. Iron-sulfur systematics and biomarker evidence demonstrate previously undescribedredox cyclicity on orbital time scales, from sulfidic to anoxic ferruginous (Fe-rich) water-columnconditions. Bulk geochemical data and sulfur isotope modeling suggest that ferruginousconditions were not a consequence of nutrient or sulfate limitation, despite overall low sulfateconcentrations in the proto–North Atlantic. Instead, fluctuations in the weathering influxes ofsulfur and reactive iron, linked to a dynamic hydrological cycle, likely drove the redox cyclicity.Despite the potential for elevated phosphorus burial in association with Fe oxides underferruginous conditions on the Tarfaya shelf, porewater sulfide generation drove extensive phosphorusrecycling back to the water column, thus maintaining widespread open-ocean anoxia.