Distribution and diel vertical migration of mesopelagic fishes in the Southern Sargasso Sea — observations through hydroacoustics and stratified catches

AbstractVertical distribution patterns and relative abundance of mesopelagic fish species and other major taxonomic groups were investigated through vertically stratified trawl sampling and hydroacoustic analyses along the subtropical convergence zone from 52° W to 70° W in the oligotrophic Sargasso Sea. Persistent stationary layers and several migrating components of different scattering characteristics were detected. The results reveal varying vertical migration patterns, including different times of onset of diel vertical migration in different depths and a migrant pathway emerging daily from the lower deep scattering layer (DSL) at dusk and migrating through the upper DSL without affecting its composition. Fish species identification was made based on morphological characteristics and confirmed by genetic barcoding analyses of subsamples. In total, 5022 fish specimens from 27 families, 62 genera and 70 species were caught. In terms of relative abundance (A) and biomass (M), catches were dominated by species of the families Myctophidae (A=59.1%, M=47.4% of total fish catch) and Melamphaidae (A=22.5%, M=17.1%). Myctophidae and Stomiidae were the most species-rich families with 31 and 12 species, respectively. Catches at the two easternmost stations were dominated by Scopelogadus mizolepis and Nannobrachium cuprarium, while Bolinichthys photothorax and Ceratoscopelus warmingii were the most abundant species in catches from the two westernmost stations. This study provides insights into distribution and vertical migration behaviour of mesopelagic fish in the Sargasso Sea and adds to our understanding of the mesopelagic community in this large oceanic area.

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The Importance of Mesozooplankton Diel Vertical Migration for Sustaining a Mesopelagic Food Web

10.1101/642975 ◽

2019 ◽

Author(s):

Thomas B. Kelly ◽

Peter C. Davison ◽

Ralf Goericke ◽

Michael R. Landry ◽

Mark D. Ohman ◽

...

Keyword(s):

Active Transport ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Deep Ocean ◽

Total Carbon ◽

Sensitivity Analyses ◽

Mesopelagic Fish ◽

Ecosystem Research ◽

Carbon Demand ◽

Gross Growth Efficiency

AbstractWe used extensive ecological and biogeochemical measurements obtained from quasi-Lagrangian experiments during two California Current Ecosystem Long-Term Ecosystem Research cruises to analyze carbon fluxes between the epipelagic and mesopelagic zones using a linear inverse ecosystem model (LIEM). Measurement constraints on the model include 14C primary productivity, dilution-based microzooplankton grazing rates, gut pigment-based mesozooplankton grazing rates (on multiple zooplankton size classes), 234Th:238U disequilibrium and sediment trap measured carbon export, and metabolic requirements of micronekton, zooplankton, and bacteria. A likelihood approach (Markov Chain Monte Carlo) was used to estimate the resulting flow uncertainties from a sample of potential flux networks. Results highlight the importance of mesozooplankton active transport (i.e., diel vertical migration) for supplying the carbon demand of mesopelagic organisms and sequestering carbon dioxide from the atmosphere. In nine water parcels ranging from a coastal bloom to offshore oligotrophic conditions, mesozooplankton active transport accounted for 18% - 84% (median: 42%) of the total carbon supply to the mesopelagic, with gravitational settling of POC (12% - 55%; median: 37%) and subduction (2% - 32%; median: 14%) providing the majority of the remainder. Vertically migrating zooplankton contributed to downward carbon flux through respiration and excretion at depth and via consumption loses to predatory zooplankton and mesopelagic fish (e.g. myctophids and gonostomatids). Sensitivity analyses showed that the results of the LIEM were robust to changes in nekton metabolic demands, rates of bacterial production, and mesozooplankton gross growth efficiency. This analysis suggests that prior estimates of zooplankton active transport based on conservative estimates of standard (rather than active) metabolism should be revisited.Contribution to the FieldUnderstanding the flows of carbon within the ocean is important for predicting how global climate will shift; yet even after decades of research, the magnitude with which the ocean sequesters carbon is highly uncertain. One reason behind this uncertainty is that a variety of mechanisms control the balance between carbon input and carbon output within the ocean. The topic of this work is to inspect the role of biological organisms in physically transferring organic carbon from the surface to the deep ocean. As opposed to other mechanisms—such as sinking particles, the biological transfer of carbon is difficult to measure directly and is often quite variable, leading to large uncertainties. Here we use an extensive set of in situ observations off the coast of southern California to model the flow of carbon through the ecosystem. The model determined that in our study area nearly half of the total transfer of carbon from the surface ocean to deep was carried out by zooplankton that swim up to the surface each night to feed. This finding has direct implications for global carbon budgets, which often underestimate this transfer of carbon.

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Patterns of distribution and abundance of larval phosichthyidae (actinopterygii, stomiiformes) in southeastern Brazilian waters

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592011000300002 ◽

2011 ◽

Vol 59 (3) ◽

pp. 213-229 ◽

Cited By ~ 1

Author(s):

Cássia Gôngora Goçalo ◽

Mario Katsuragawa ◽

Ilson Carlos Almeida da Silveira

Keyword(s):

Vertical Distribution ◽

Water Column ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Distribution Patterns ◽

Southeastern Brazil ◽

Patterns Of Distribution ◽

Oceanic Region ◽

Brazil Current ◽

Horizontal And Vertical Distribution

Horizontal and vertical distribution patterns and abundance of larval phosichthyids were investigated from oblique and depth-stratified towns off Southeastern brazilian waters, from São Tomé cape (41ºW.; 22ºS.) to São Sebastião island (45ºW.; 24ºS.). The sampling was performed during two cruises (January/2002 -summer; August/2002 -winter). Overall 538 larvae of Phosichthyidae were collected during summer and 158 in the winter. Three species, Pollichthys mauli, Vinciguerria nimbaria and Ichthyioccoccus sp. occurred in the area, but Ichthyioccoccus sp. was extremely rare represented by only one specimen, caught in the oceanic region during the summer. Geographically, larval were concentrated in the oceanic region, and vertically distributed mainly between the surface and 80 m depth in the summer and winter. Larvae were more abundant during the night, performing a diel vertical migration in the water column. The results suggest that the meandering and eddies of Brazil Current play important role on the transport and distribution patterns of larval phosichthyids over the oceanic and neritic area in the Southeastern Brazil.

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Diel Vertical migration of marine organisms and the biological carbon pump

10.5194/egusphere-egu21-198 ◽

2021 ◽

Author(s):

Jerome Pinti ◽

Tim DeVries ◽

Tommy Norin ◽

Camila Serra-Pompei ◽

Roland Proud ◽

...

Keyword(s):

Carbon Sequestration ◽

Food Web ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Marine Organisms ◽

Trophic Levels ◽

Mesopelagic Fish ◽

Pelagic Food Web ◽

Carbon Pump ◽

Biological Carbon Pump

Diel Vertical Migration (DVM) is a key feature of pelagic and mesopelagic ecosystems, mainly driven by predator-prey interactions along a time-varying vertical gradient of light. Marine organisms including meso-zooplankton and fish typically hide from visual predators at depth during daytime and migrate up at dusk to feed in productive near-surface waters during nighttime. Specific migration patterns, however, vary tremendously, for instance in terms of residency depth during day and night. In addition to environmental parameters such as light intensity and oxygen concentration, the migration pattern of each organism is intrinsically linked to the patterns of its conspecifics, its prey, and its predators through feedbacks that are hard to understand&#8212;but important to consider.DVM not only affects trophic interactions, but also the biogeochemistry of the world&#8217;s oceans.&#160; Organisms preying at the surface and actively migrating vertically transport carbon to depth, contributing to the biological carbon pump, and directly connecting surface production with mesopelagic and demersal ecosystems.Here, we present a method based on a game-theoretic trait-based mechanistic model that enables the optimal DVM patterns for all organisms in a food-web to be computed simultaneously. The results are used to investigate the contributions of the different food-web pathways to the active component of the biological carbon pump. We apply the method to a modern pelagic food-web (comprised of meso- and macro-zooplankton, forage fish, mesopelagic fish, large pelagic fish and gelatinous organisms), shedding light on the direct effects that different trophic levels can have on the DVM behaviours of each other. The model is run on a global scale to assess the carbon export mediated by different functional groups, through fecal pellet production, carcasses sinking and respiration.Finally, the model output is coupled to an ocean inverse circulation model to assess the carbon sequestration potential of the different export pathways. Results indicate that the carbon sequestration mediated by fish is much more important than presently recognised in global assessments of the biological carbon pump. The work we present relates to contemporary ecosystems, but we also explain how it can be adapted to fit any pelagic food-web structure to assess the contribution of the active biological pump to the global carbon cycle in past ecosystems.

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Energetic costs and benefits of cyclic habitat switching: a bioenergetics model analysis of diel vertical migration in coregonids

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2011-012 ◽

2011 ◽

Vol 68 (4) ◽

pp. 706-717 ◽

Cited By ~ 18

Author(s):

Susan Busch ◽

Brett M. Johnson ◽

Thomas Mehner

Keyword(s):

Fish Species ◽

Vertical Migration ◽

Growth Rates ◽

Diel Vertical Migration ◽

Night Time ◽

Energetic Costs ◽

Efficient Strategy ◽

Parameterized Model ◽

Energetic Constraints ◽

Lake Stechlin

Recent studies on diel vertical migration (DVM) of two coregonid species ( Coregonus spp.) in Lake Stechlin (Germany) have suggested that the nocturnal distribution of fish is linked with metabolic benefits. We used a spatially explicit bioenergetics-based foraging model to test whether energetic constraints contribute to explain DVM of both species. The newly parameterized model was compared with independent data from Lake Stechlin that covered a 9 month period. Predicted growth rates matched observed growth rates of each fish species reasonably well. The simulation of different migration scenarios showed that even slight changes in night-time depths modified growth rates, primarily owing to temperature-dependent respiration. Fish that performed DVM grew faster than nonmigratory fish that occupied deep hypolimnetic water over a diel cycle. However, the most energy-efficient strategy simulated had fish remaining within the metalimnion. Here, energetic benefits (foraging) clearly outweighed higher energetic costs (respiration) in the warmer waters. Although DVM can be energetically beneficial, it is not the most efficient strategy performed by coregonids in Lake Stechlin. We suggest that multiple factors, rather than bioenergetics efficiency alone, are the evolutionary basis for DVM of many freshwater fish species.

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Metazoans, migrations, and the ocean's biological carbon pump

10.1101/2021.03.22.436489 ◽

2021 ◽

Author(s):

Jérôme Pinti ◽

Timothy DeVries ◽

Tommy Norin ◽

Camila Serra-Pompei ◽

Roland Proud ◽

...

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Euphotic Zone ◽

Mesopelagic Fish ◽

Carbon Export ◽

Carbon Pump ◽

Oceanic Carbon ◽

Unregulated Fishing ◽

Global Carbon ◽

Biological Carbon Pump

Diel vertical migration of fish and other metazoans actively transports organic carbon from the ocean surface to depth, contributing to the biological carbon pump. Here, we use a global vertical migration model to estimate global carbon fluxes and sequestration by fish and metazoans due to respiration, fecal pellets, and deadfalls. We estimate that fish and metazoans contribute 5.2 PgC/yr (2.1-8.8PgC/yr) to passive export out of the euphotic zone. Together with active transport, we estimate that fish are responsible for 20% (9-29%) of global carbon export, and 32% (18-43%) of oceanic carbon sequestration, with forage and deep-dwelling mesopelagic fish contributing the most. This essential ecosystem service could be at risk from unregulated fishing on the high seas.

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Diel vertical migration and feeding of chaetognaths in coastal waters of the eastern Mediterranean

Biologia ◽

10.2478/s11756-010-0024-8 ◽

2010 ◽

Vol 65 (2) ◽

Cited By ~ 4

Author(s):

George Kehayias ◽

Dimitris Kourouvakalis

Keyword(s):

Vertical Migration ◽

Coastal Waters ◽

Diel Vertical Migration ◽

Eastern Mediterranean ◽

Abundant Species ◽

Migration Pattern ◽

Food Type ◽

Feeding Intensity ◽

High Preference ◽

Diel Vertical Distribution

AbstractThis study investigates the diel vertical distribution and the diet of the most important chaetognath species found in the 0–50 m surface layer of a coastal area in the eastern Mediterranean during a 24-hour period in July 2004. Among the recorded chaetognaths, Sagitta enflata was the most abundant species (41.6%), followed by S. minima (32.5%) and S. serratodentata (20.8%). Those three species exhibited a “twilight migration” pattern, with only small differences among them. Vertical separation was found between S. enflata and S. minima. Both species preyed mainly on cladocerans, although copepods were the most abundant group in the zooplankton assemblage. The chaetognath species followed partially the diel vertical migration of their prey. S. enflata showed high feeding intensity at different times in both day and night, while S. minima fed more intensively at midday (12:00) and at dusk (20:00), and S. serratodentata in the morning (08:00). It seems that in order to coexist in an area of low productivity the chaetognath species follow the basic ecological rules of space, time and food-type separation, in order to reduce the inter- and intra-specific competition. The high preference of S. minima and especially of S. enflata for the cladocerans made them probably the most important predators of cladocerans during summer.

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Microplastic interactions with North Atlantic mesopelagic fish

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv241 ◽

2015 ◽

Vol 73 (4) ◽

pp. 1214-1225 ◽

Cited By ~ 106

Author(s):

Amy L. Lusher ◽

Ciaran O'Donnell ◽

Rick Officer ◽

Ian O'Connor

Keyword(s):

Marine Environment ◽

North Atlantic ◽

Vertical Migration ◽

Deep Sea ◽

Diel Vertical Migration ◽

Euphotic Zone ◽

Mesopelagic Fish ◽

Marine Biota ◽

Northeast Atlantic ◽

Migration Behaviour

Abstract Microplastics in the marine environment are well documented, and interactions with marine biota have been described worldwide. However, interactions with vertically migrating fish are poorly understood. The diel vertical migration of mesopelagic fish represents one, if not the largest, vertical migration of biomass on the planet, and is thus an important link between the euphotic zone, transporting carbon and other nutrients to global deep sea communities. Knowledge of how mesopelagic fish interact and distribute plastic as a marine contaminant is required as these populations have been identified as a potential global industrial fishery for fishmeal production. Ingestion of microplastic by mesopelagic fish in the Northeast Atlantic was studied. Approximately 11% of the 761 fish examined had microplastics present in their digestive tracts. No clear difference in ingestion frequency was identified between species, location, migration behaviour, or time of capture. While ingesting microplastic may not negatively impact individual mesopelagic fish, the movement of mesopelagic fish from the euphotic zone to deeper waters could mediate transfer of microplastics to otherwise unexposed species and regions of the world's oceans.

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Diel vertical migration of fish in a Neotropical reservoir

Marine and Freshwater Research ◽

10.1071/mf16009 ◽

2017 ◽

Vol 68 (6) ◽

pp. 1070 ◽

Cited By ~ 2

Author(s):

I. G. Prado ◽

P. S. Pompeu

Keyword(s):

Power Plant ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Power Plants ◽

Hydroelectric Power Plant ◽

Distribution Patterns ◽

Fish Passage ◽

Fish Distribution ◽

Hydroelectric Power ◽

Operational Variables

Vertical distribution of fish was studied immediately upstream of the Três Marias hydroelectric power plant dam from December 2010 to December 2011. Eighteen field trips were conducted for hydroacoustic sampling over a period of 24h each time, with 6-h diel sampling intervals within each of the 18 sample dates. Gill nets were used to collect information on fish species composition and length. The greater fish abundance near the surface during the night and at higher depths during the daytime over a 1-day period suggests that the behavioural phenomenon known as diel vertical migration occurs at Três Marias reservoir. Therefore, the aim of the present study was to evaluate the occurrence of diel vertical migration of fish in a Neotropical reservoir, the possible relationship with the operation of the hydroelectric power plant and the variables that may affect fish distribution in water column. Analysis of some limnological and operational variables showed that water transparency, temperature and dissolved oxygen were correlated with vertical fish distribution patterns. These results are important for proposing management measures to mitigate the effects of hydroelectric power plants on fish, such as fish passage through turbines.

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