Category: Marine ecology

Machine learning highlights the importance of primary and secondary production in determining habitat for marine fish and macroinvertebrates

Kevin D. Friedland, Michelle Bachman, Andrew Davies, Romain Frelat, M. Conor McManus, Ryan Morse, Bradley A. Pickens, Szymon Smoliński, Kisei Tanaka

Abstract

1. Species distribution models for marine organisms are increasingly used for a range of applications, including spatial planning, conservation, and fisheries management. These models have been constructed using a variety of mathematical forms and drawing on both physical and biological independent variables; however, what might be called first‐generation models have mainly followed the form of linear models, or smoothing splines, informed by data collected in the context of fish surveys.
2. The performance of different classes of variables were tested in a series of species occurrence models built with machine learning methods, specifically evaluating the potential contribution of lower trophic level data. Random forest models were fitted based on the classification of the absence/presence for fish and macroinvertebrates surveyed on the US Northeast Continental Shelf.
3. The potential variables included physical, primary production, secondary production, and terrain variables. For accepted model fits, six variable importance measures were computed, which collectively showed that physical and secondary production variables make the greatest contribution across all models. In contrast, terrain variables made the least contribution to these models.
4. Multivariable analyses that account for all performance measures reinforce the role of water depth and temperature in defining species presence and absence; however, chlorophyll concentration and some specific zooplankton taxa, such as Metridia lucens and Paracalanus parvus, also make important contributions with strong seasonal variations.
5. Our results suggest that lower trophic level variables, if available, are valuable in the creation of species distribution models for marine organisms.

[sendpaper paperurl=”2021_Friedland.pdf”]

Full Citation

Friedland, KD, Bachman, M, Davies, A, Frelat, R, McManus, MC, Morse, R, Pickens, BA, Smoliński, S, Tanaka, K. (2021) Machine learning highlights the importance of primary and secondary production in determining habitat for marine fish and macroinvertebrates. Aquatic Conservation: Marine and Freshwaster Ecosystems, 1–17. https://doi.org/10.1002/aqc.3527

Manuscript DOI

https://doi.org/10.1002/aqc.3527

Long‐term Observations Reveal Environmental Conditions and Food Supply Mechanisms at an Arctic Deep‐Sea Sponge Ground

Ulrike Hanz, Emyr Martyn Roberts, Gerard Duineveld, Andrew Davies, Hans van Haren, Hans Tore Rapp, Gert‐Jan Reichart, Furu Mienis

Abstract

Deep‐sea sponge grounds are hotspots of benthic biomass and diversity. To date, very limited data exist on the range of environmental conditions in areas containing deep‐sea sponge grounds and which factors are driving their distribution and sustenance. We investigated oceanographic conditions at a deep‐sea sponge ground located on an Arctic Mid‐Ocean Ridge seamount. Hydrodynamic measurements were performed along Conductivity‐Temperature‐Depth transects, and a lander was deployed within the sponge ground that recorded near‐bottom physical properties as well as vertical fluxes of organic matter over an annual cycle. The data demonstrate that the sponge ground is found at water temperatures of −0.5°C to 1°C and is situated at the interface between two water masses at only 0.7° equatorward of the turning point latitude of semi‐diurnal lunar internal tides. Internal waves supported by vertical density stratification interact with the seamount topography and produce turbulent mixing as well as resuspension of organic matter with temporarily very high current speeds up to 0.72 m s⁻¹. The vertical movement of the water column delivers food and nutrients from water layers above and below toward the sponge ground. Highest organic carbon flux was observed during the summer phytoplankton bloom period, providing fresh organic matter from the surface. The flux of fresh organic matter is unlikely to sustain the carbon demand of this ecosystem. Therefore, the availability of bacteria, nutrients, and dissolved and particulate matter, delivered by tidally forced internal wave turbulence and transport by horizontal mean flows, likely plays an important role in meeting ecosystem‐level food requirements.

[sendpaper paperurl=”2021_Hanz.pdf”]

Full Citation

Hanz, U., Roberts, E. M., Duineveld, G., Davies, A., Van Haren, H., Rapp, H. T., Reichart, G. J. and Mienis, F. 2021. Long–term observations reveal environmental conditions and food supply mechanisms at an Arctic deep‐sea sponge ground. — Journal of Geophysical Research: Oceans 126: e2020JC016776. 10.1029/2020jc016776

Manuscript DOI

https://doi.org/10.1029/2020JC016776

Climate change winner in the deep sea? Predicting the impacts of climate change on the distribution of the glass sponge Vazella pourtalesii

Beazley L, Kenchington E, Murillo FJ, Brickman D, Wang Z, Davies AJ, Roberts EM, Rapp HT

Shallow-water sponges are often cited as being ‘climate change winners’ due to their resiliency against climate change effects compared to other benthic taxa. However, little is known of the impacts of climate change on deep-water sponges. The deep-water glass sponge Vazella pourtalesii is distributed off eastern North America, forming dense sponge grounds with enhanced biodiversity on the Scotian Shelf off Nova Scotia, Canada. While the strong natural environmental variability that characterizes these sponge grounds suggests this species is resilient to a changing environment, its physiological limitations remain unknown, and the impact of more persistent anthropogenic climate change on its distribution has never been assessed. We used Random Forest and generalized additive models to project the distribution of V. pourtalesii in the northwest Atlantic using environmental conditions simulated under moderate and worst-case CO2 emission scenarios. Under future (2046-2065) climate change, the suitable habitat of V. pourtalesii will increase up to 4 times its present-day size and shift into deeper waters and higher latitudes, particularly in its northern range where ocean warming will serve to improve the habitat surrounding this originally sub-tropical species. However, not all areas projected as suitable habitat in the future will realistically be populated, and the reduced likelihood of occurrence in its core habitat on the Scotian Shelf suggests that the existing Vazella sponge grounds may be negatively impacted. An effective monitoring programme will require tracking changes in the density and distribution of V. pourtalesii at the margins between core habitat and where losses and gains were projected.
[sendpaper paperurl=”2021_Beazley.pdf”]

Full Citation

Beazley L, Kenchington E, Murillo FJ, Brickman D, Wang Z, Davies AJ, Roberts EM, Rapp HT (2021) Climate change winner in the deep sea? Predicting the impacts of climate change on the distribution of the glass sponge Vazella pourtalesii. Marine Ecology Progress Series 657: 1-23.

Manuscript DOI

https://www.int-res.com/abstracts/meps/v657/p1-23/

Editorial: Advances in 3D Habitat Mapping of Marine Ecosystem Ecology and Conservation

Renata Ferrari, Javier X. Leon, Andrew J. Davies, John H. R. Burns, Stuart A. Sandin, Will F. Figueira and Manuel Gonzalez-Rivero

Abstract

Advances in 3D technology have enabled low-cost and accurate measurements of habitat structure and organism size in both terrestrial and marine environments. However, there is still a need for guidance on how to apply novel 3D technologies for marine ecology and conservation. Multiple teams from around the world are leading the application of 3D photogrammetry in marine ecosystems. The widespread adoption of 3D methodologies produces a growing need for agreed standards to assess the quality of 3D data (e.g., error metrics). Similarly, standardized techniques where possible, will ensure collaboration and compatibility of 3D data across space and time.

This Research Topic is a first step toward the standardization of methods and communication of the state of the field to the wider audience in marine science and conservation using or considering the use of 3D technologies. The Topic provides relevant information that: (1) defines standard methods for the application of 3D technologies to marine ecosystem ecology and conservation, (2) advances fundamental marine ecological and conservation knowledge relevant to the habitat structure of marine ecosystems; and (3) highlights knowledge gaps and directions to move toward a high-resolution 3D map of the world’s oceans.

The Research Topic focuses on the use of high-resolution 3D reconstructions of underwater ecosystems. It includes 13 articles, of which six are original research articles, one is a perspective, and six are methodological advances. Most of the original research articles also included a methodological validation or comparison. The geographic scope of this Research Topic ranges from the Caribbean to Greenland to the Pacific Islands and Australasia. Nine articles were conducted in coral reefs, three in temperate rocky reefs, and one on a deep-sea cliff, which highlights the versatility of 3D technologies. The diverse group of articles explored the relationship between habitat features, benthic and fish abundance, health, diversity, the potential of reef scape genomics, and the effectiveness of marine protection. A range of equipment from action cameras and DSLRs, to machine vision cameras, underwater robots, and echo-sounders were used to generate 3D reconstructions, emphasizing how a broad range of 3D technologies can benefit a wide variety of end users and applications. Similarly, the breath of the research published in this Research Topic captured 3D reconstructions of sub-millimeter resolutions, as well as 3D maps across large spatial extents.

[sendpaper paperurl=”2022_Ferrari_Frontiers.pdf”]

Full Citation

Ferrari R, Leon JX, Davies AJ, Burns JHR, Sandin SA, Figueira WF, Gonzalez-Rivero M (2022) Editorial: Advances in 3D Habitat Mapping of Marine Ecosystem Ecology and Conservation. Front Mar Sci 8

Manuscript DOI

https://www.frontiersin.org/articles/10.3389/fmars.2021.827430/full

Connectivity of sponge grounds in the deep sea: genetic diversity, gene flow and oceanographic pathways in the fan-shaped sponge Phakellia ventilabrum in the northeast Atlantic

Sergi Taboada, Connie Whiting, Shuangqiang Wang, Pilar Ríos, Andrew Davies, Furu Mienis, Ellen Kenchington, Paco Cárdenas, Alex Cranston, Vasiliki Koutsouveli, Javier Cristobo, Hans-Tore Rapp, Jim Drewery, Francisco Baldó, Christine Morrow, Bernard Picton, Joana Xavier, María Belén Arias, Ana Riesgo

Abstract

A complex interplay of biotic and abiotic factors underpins the distribution of species and operates across different levels of biological organization and life history stages. Understanding ecosystem engineer reproductive traits is critical for comprehending and managing the biodiversity-rich habitats they create. Little is known about how the reproduction of the reef-forming worm, Sabellaria alveolata, varies across environmental gradients. By integrating broad-scale environmental data with in-situ physiological data in the form of biochemical traits, we identified and ranked the drivers of intraspecific Little is known about dispersal in deep-sea sponges, yet understanding patterns of gene flow and connectivity is essential for their effective management. Given rising pressure from harmful anthropogenic activities, schemes that manage resource extraction whilst conserving species diversity are increasingly necessary. Here, we used ddRADseq derived SNPs to investigate the genetic diversity and connectivity for the deep-sea sponge Phakellia ventilabrum across the northeast Atlantic Ocean (from the Cantabrian Sea to Norway). The analysis of 166 individuals collected from 57 sampling stations were grouped into 17 different areas, including two MPAs, one SAC and other areas with different levels of protection. The 4,017 neutral SNPs we uncovered indicated high connectivity and panmixis amongst the majority of areas, spanning a ca. 2,500-kilometre range and depths of 99–900 m. This was likely due to the presence of strong ocean currents aiding larval transport, as supported by our migration analysis and also by 3D particle tracking modelling using information on the reproductive cycle of P. ventilabrum. We also observed significant genetic similarity between samples from the Cantabrian Sea and Roscoff (France) as compared to the remainder of the collection areas, likely arising from physical drivers such as prevailing current circulation patterns and topographic features, acting as barriers for gene flow. Despite this, our results suggest that all protected areas studied are well connected with each other. The relatively low genetic diversity observed in all areas, though, highlights the potential fragility of this species to changing climates, which might compromise resilience to future threats.

Manuscript DOI

Preprint

Life in the Fast Lane: Modeling the Fate of Glass Sponge Larvae in the Gulf Stream

Shuangqiang Wang, Ellen Kenchington, Zeliang Wang and Andrew J. Davies

Abstract

Effective conservation management of deep-sea sponges, including design of appropriate marine protected areas, requires an understanding of the connectivity between populations throughout a species’ distribution. We provide the first consideration of larval connectivity among deep-sea sponge populations along the southeastern coast of North America, illustrate the influence of the Gulf Stream on dispersal, and complement published distribution models by evaluating colonization potential. Connectivity among known populations of the hexactinellid sponge Vazella pourtalesii was simulated using a 3-D biophysical dispersal model throughout its distribution from Florida, United States to Nova Scotia, Canada. We found no exchange with an estimated pelagic larval duration of 2 weeks between populations north and south of Cape Hatteras, North Carolina at surface, mid-water and seabed release depths, irrespective of month of release or application of a horizontal diffusion constant specific to cross-Gulf Stream diffusivity. The population north of Cape Hatteras and south of Cape Cod was isolated. There was some evidence that Gulf Stream eddies formed near Cape Hatteras could travel to the northwest, connecting the populations in the two sub-regions, however that would require a much longer pelagic duration than what is currently known. More likely almost all larval settlement will be in the immediate area of the adults. At sub-regional scales, connectivity was found from the Strait of Florida through to the Blake Plateau, southeastern United States, with the latter area showing potential for recruitment from more than one source population. The influence of the Charleston Bump, a shallow feature rising from the Blake Plateau, was substantial. Particles seeded just north of the Bump were transported greater distances than those seeded to the south, some of which were caught in an associated gyre, promoting retention at the seabed. To the north on the Scotian Shelf, despite weaker currents and greater distances between known occurrences, unidirectional transport was detected from Emerald Basin to the Northeast Channel between Georges and Browns Banks. These major conclusions remained consistent through simulations run with different averaging periods for the currents (decades to daily) and using two ocean model products (BNAM and GLORYS12V1).

[sendpaper paperurl=”2021_Wang_Frontiers.pdf”]

Full Citation

Wang S, Kenchington E, Wang Z, Davies AJ (2021) Life in the Fast Lane: Modeling the Fate of Glass Sponge Larvae in the Gulf Stream. Front Mar Sci 8

Manuscript DOI

https://doi.org/10.3389/fmars.2021.701218

Trends in phytoplankton communities within large marine ecosystems diverge from the global ocean

Kevin D. Friedland, John R. Moisan, Aurore A. Maureaud, Damian C. Brady, Andrew J. Davies, Steven J. Bograd, Reg A. Watson, and Yannick Rousseau

Abstract

Large marine ecosystems (LMEs) are highly productive regions of the world ocean under anthropogenic pressures; we analyzed trends in sea surface temperature (SST), cloud fraction (CF), and chlorophyll concentration (CHL) over the period 1998–2019. Trends in these parameters within LMEs diverged from the world ocean. SST and CF inside LMEs increased at greater rates inside LMEs, whereas CHL decreased at a greater rates. CHL declined in 86% of all LMEs and of those trends, 70% were statistically significant. Complementary analyses suggest phytoplankton functional types within LMEs have also diverged from those characteristic of the world ocean, most notably, the contribution of diatoms and dinoflagellates, which have declined within LMEs. LMEs appear to be warming rapidly and receiving less solar radiation than the world ocean, which may be contributing to changes at the base of the food chain. Despite increased fishing effort, fishery yields in LMEs have not increased, pointing to limitations related to productivity. These changes raise concerns over the stability of these ecosystems and their continued ability to support services to human populations.

[sendpaper paperurl=”2021_Friedland_LMS.pdf”]

Full Citation

Friedland KD, Moisan JR, Maureaud AA, Brady DC, Davies AJ, Bograd SJ, Watson RA, Rousseau Y (2021) Trends in phytoplankton communities within large marine ecosystems diverge from the global ocean. Canadian Journal of Fisheries and Aquatic Sciences 78: 1689-1700

Manuscript DOI

https://dx.doi.org/10.1139/cjfas-2020-0423

Environmental optima for an ecosystem engineer: a multidisciplinary trait-based approach

Amelia Curd, Aurélien Boyé, Céline Cordier, Fabrice Pernet, Louise B. Firth, Laura E. Bush, Andrew J. Davies, Fernando P. Lima, Claudia Meneghesso, Claudie Quéré, Rui Seabra, Mickaël Vasquez & Stanislas F. Dubois

Abstract

A complex interplay of biotic and abiotic factors underpins the distribution of species and operates across different levels of biological organization and life history stages. Understanding ecosystem engineer reproductive traits is critical for comprehending and managing the biodiversity-rich habitats they create. Little is known about how the reproduction of the reef-forming worm, Sabellaria alveolata, varies across environmental gradients. By integrating broad-scale environmental data with in-situ physiological data in the form of biochemical traits, we identified and ranked the drivers of intraspecific reproductive trait variability (ITV). ITV was highest in locations with variable environmental conditions, subjected to fluctuating temperature and hydrodynamic conditions. Our trait selection pointed to poleward sites being the most physiologically stressful, with low numbers of irregularly shaped eggs suggesting potentially reduced reproductive success. Centre-range individuals allocated the most energy to reproduction, with the highest number of intermediate-sized eggs, whilst equatorward sites were the least physiologically stressful, thus confirming the warm-adapted nature of our model organism. Variation in total egg diameter and relative fecundity were influenced by a combination of environmental conditions, which changed depending on the trait and sampling period. An integrated approach involving biochemical and reproductive traits is essential for understanding macro-scale patterns in the face of anthropogenic-induced climate change across environmental and latitudinal gradients.

[sendpaper paperurl=”2021_Curd.pdf”]

Full Citation

Curd A, Boyé A, Cordier C, Pernet F, Firth LB, Bush LE, Davies AJ, Lima FP, Meneghesso C, Quéré C, Seabra R, Vasquez M, Dubois SF (2021) Environmental optima for an ecosystem engineer: a multidisciplinary trait-based approach. Sci Rep-UK 11

Manuscript DOI

https://doi.org/10.1038/s41598-021-02351-7

The fundamental links between climate change and marine plastic pollution

Helen V. Ford, Nia H. Jones, Andrew J. Davies, Brendan J. Godley, Jenna R. Jambeck, Imogen E. Napper, Coleen C. Suckling, Gareth J. Williams, Lucy Woodall, Heather J. Koldewey

Abstract

Designing conservation networks requires a well-structured framework for achieving essential objectives such as Plastic pollution and climate change have commonly been treated as two separate issues and sometimes are even seen as competing. Here we present an alternative view that these two issues are fundamentally linked. Primarily, we explore how plastic contributes to greenhouse gas (GHG) emissions from the beginning to the end of its life cycle. Secondly, we show that more extreme weather and floods associated with climate change, will exacerbate the spread of plastic in the natural environment. Finally, both issues occur throughout the marine environment, and we show that ecosystems and species can be particularly vulnerable to both, such as coral reefs that face disease spread through plastic pollution and climate-driven increased global bleaching events. A Web of Science search showed climate change and plastic pollution studies in the ocean are often siloed, with only 0.4% of the articles examining both stressors simultaneously. We also identified a lack of regional and industry-specific life cycle analysis data for comparisons in relative GHG contributions by materials and products. Overall, we suggest that rather than debate over the relative importance of climate change or marine plastic pollution, a more productive course would be to determine the linking factors between the two and identify solutions to combat both crises.

[sendpaper paperurl=”2021_Ford_STOTEN.pdf”]

Full Citation

Ford HV, Jones NH, Davies AJ, Godley BJ, Jambeck JR, Napper IE, Suckling CC, Williams GJ, Woodall L, Koldewey HJ (2021) The fundamental links between climate change and marine plastic pollution. Science of the Total Environment 806 (2022) 150392

Manuscript DOI

https://doi.org/10.1016/j.scitotenv.2021.150392