Periodic Reporting for period 1 - CWCC-Dynamics (Cold-Water Coral Community Dynamics)
Période du rapport: 2021-04-01 au 2023-03-31
Mounds and margins on the North Atlantic host highly diverse and structurally complex megabenthic communities, such as cold-water coral (CWC) reefs. These communities have been widely impacted by fishing activities, and thus CWC reefs are identified as vulnerable marine ecosystems in need of protection. Recently, several deep-sea environments (e.g. mounts, canyons) hosting CWC reefs and other vulnerable marine ecosystems, have been integrated in Marine Protected Areas (MPA). However, few of these MPAs have incorporated management plans. To establish suitable management policies, it is required to implement monitoring strategies that account for these diverse community dynamics and how they may be influenced by environmental drivers. Elucidating deepsea benthic community dynamics, represents an important challenge for future research especially as management of human impacts becomes a priority. The Cold Water Community Dynamic's project (CWCC-Dynamics) main objectives are to assess the dynamics in CWC communities' and other vulnerable marine ecosystems and examine how different environmental factors may be influencing them.
The CWCC-Dynamics project has been structured around two work packages (WP): WP1, focused on the assessment of temporal variability in cold water coral (CWC) communities’ structure and structural complexity and WP2, focused on the identification of environmental forcing factors driving changes in CWC communities’ structure and structural complexity.
During the first 16 months of the project, the fellow focused on fulfilling WP1 by assessing: i) changes on the structural complexity of CWC colonies as well as other sessile taxa that play a paramount role in creating a complex three-dimensional structure such as sponge or actinians; ii) and by characterizing changes in species diversity and abundance to assess changes in community composition at different time scales. To achieve these goals integrated standard benthic image analyses approaches, such as the measurement of CWC colony and sponge surface with the open-source software Image J, with state-of-the-art convolutional neural networks (CNN), such as Mask-R-CNN or You Only Look Once (Yolo) using the free open-source programming language Python were combined.
From month 12 to 24 of the proposal, the fellow worked on the development of WP2. To fulfil this objective atmospheric data were acquired from meteorological buoys in the proximities of the study areas and sea surface chlorophyll concentrations were acquired from the European Union Earth observatory Programme, Copernicus. After correcting potential outliers, the relationship between variations in structural complexity and community composition were explored by means of different statistical approaches.
The main results achieved during the CWCC-Dynamics are summarised in 2 main blocks:
1) The Lofoten-Vesterålen cabled video-observatory (LoVe), equipped with oceanographic multiparametric sensors, has been monitoring a D. pertusum reef, located at 260 m depth. From October 2013 to January 2018 this reefs dynamics were studied. Non-metric multi-dimensional scaling analysis revealed that assemblage composition significantly changed among seasons: autumn assemblages were characterized by pandalid shrimps and pagurid crabs, winter assemblages were depicted by squat lobsters and crinoids, and spring assemblages were characterized by gorgonocephalid ophiuroids and the actinian Prothoptea simplex. Organism counts fluctuated seasonally (Figure 1). These shifts in community composition and variations in organism abundance appeared to be linked to changes in primary productivity and the occurrence of different water masses. The present results were presented in the 8th International Symposium of Deep Sea Corals (29th of May to 2nd of June 2023, Edinburgh, Scotland) and were used in formation activities held at NIOZ graduate student Summer School (18th of July, 2023).
2) First quantitative characterization of temporal dynamics of a Vazella pourtalesii and actinian grounds in the Sambro bank conservation area, North Western Atlantic Shelf:
Community dynamics in a V. pourtalesii ground were studied. An unidentified actinian and the red fish Sebastes fasciatus were the most abundant species accounting for 93% and 4% of all observed organisms, respectively. Non-metric multidimensional scaling analysis revealed that assemblage composition did not significantly differ between seasons. However, it was observed that sessile taxa abundances decreased during benthic storms that influence the near-bed hydrodynamics. These storms could last for several days causing high sediment resuspension and the dislodgment or partial burial of sponge and actinian individuals.
These results have been disseminated in international congresses, pier review articles and higher education activities.
During the first 16 months of the project, the fellow focused on fulfilling WP1 by assessing: i) changes on the structural complexity of CWC colonies as well as other sessile taxa that play a paramount role in creating a complex three-dimensional structure such as sponge or actinians; ii) and by characterizing changes in species diversity and abundance to assess changes in community composition at different time scales. To achieve these goals integrated standard benthic image analyses approaches, such as the measurement of CWC colony and sponge surface with the open-source software Image J, with state-of-the-art convolutional neural networks (CNN), such as Mask-R-CNN or You Only Look Once (Yolo) using the free open-source programming language Python were combined.
From month 12 to 24 of the proposal, the fellow worked on the development of WP2. To fulfil this objective atmospheric data were acquired from meteorological buoys in the proximities of the study areas and sea surface chlorophyll concentrations were acquired from the European Union Earth observatory Programme, Copernicus. After correcting potential outliers, the relationship between variations in structural complexity and community composition were explored by means of different statistical approaches.
The main results achieved during the CWCC-Dynamics are summarised in 2 main blocks:
1) The Lofoten-Vesterålen cabled video-observatory (LoVe), equipped with oceanographic multiparametric sensors, has been monitoring a D. pertusum reef, located at 260 m depth. From October 2013 to January 2018 this reefs dynamics were studied. Non-metric multi-dimensional scaling analysis revealed that assemblage composition significantly changed among seasons: autumn assemblages were characterized by pandalid shrimps and pagurid crabs, winter assemblages were depicted by squat lobsters and crinoids, and spring assemblages were characterized by gorgonocephalid ophiuroids and the actinian Prothoptea simplex. Organism counts fluctuated seasonally (Figure 1). These shifts in community composition and variations in organism abundance appeared to be linked to changes in primary productivity and the occurrence of different water masses. The present results were presented in the 8th International Symposium of Deep Sea Corals (29th of May to 2nd of June 2023, Edinburgh, Scotland) and were used in formation activities held at NIOZ graduate student Summer School (18th of July, 2023).
2) First quantitative characterization of temporal dynamics of a Vazella pourtalesii and actinian grounds in the Sambro bank conservation area, North Western Atlantic Shelf:
Community dynamics in a V. pourtalesii ground were studied. An unidentified actinian and the red fish Sebastes fasciatus were the most abundant species accounting for 93% and 4% of all observed organisms, respectively. Non-metric multidimensional scaling analysis revealed that assemblage composition did not significantly differ between seasons. However, it was observed that sessile taxa abundances decreased during benthic storms that influence the near-bed hydrodynamics. These storms could last for several days causing high sediment resuspension and the dislodgment or partial burial of sponge and actinian individuals.
These results have been disseminated in international congresses, pier review articles and higher education activities.
It was initially ambitioned that the CWCC-Dynamics project would generate 3 scientific articles, however the research results from this project have a greater potential and 6 articles will be generated. So far 2 articles addressing the dynamics of megabenthic species and the development of CWC structures have been published in open access journals:
Grinyó, J., Aguzzi, J., Kenchington, E., Costa, C., Hanz, U., & Mienis, F. (2023). Occurrence and behavioral rhythms of the endangered Acadian redfish (Sebastes fasciatus) in the Sambro Bank (Scotian Shelf). Frontiers in Marine Science, 10, 1158283.
Corbera, G., Lo Iacono, C., Simarro, G., Grinyó, J., Ambroso, S., Huvenne, V. A., Mienis, F., Carreiro-Silva, M., Martin, I., Mano, B., Orejas, C., Larsson, A., Hennige, S., & Gori, A. (2022). Local-scale feedbacks influencing cold-water coral growth and subsequent reef formation. Scientific Reports, 12(1), 20389.
Four additional articles are in different stages of development, one of which has already been submitted to a peer review journal while the others are in different stages of development.
Grinyó, J., Aguzzi, J., Ortensi, L., Kenchington, E., Kenchington, T., Violino, S., Hanz, U., Santín, A., Nattkemper, T.W. & Mienis, F. (Submitted September 2023) What glass sponges do when no one is looking? Vazella pourtalesii phenology: responses to sediment deposition, passive movement, and contracting behavior. Deep-Sea Research Part I.
Grinyó, J., Aguzzi, J., Garcia, R., Ruscio, F., Kenchington, E., Canepa, A., Costa, C., Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Temporal dynamics of megabenthis species on a Vazella pourtalesii sponge ground.
Grinyó, J., Aguzzi, J., Hassan., A., Saha, A., Canepa, A., Garcia, R., Ruscio, F. Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Cold water community dynamics in a Desmophyllum pertusum reef on the Norwegian continental shelf.
Grinyó, J., Aguzzi, J., Hassan., A., Saha, A., Garcia, R., Ruscio, F. Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Benthic storm effects on several deep-sea vulnerable marine ecosystems on the North Atlantic.
The CWCC-Dynamics results will be useful to identify the vulnerability of cold-water coral communities to environmental change and apply this knowledge to maximize the protection, management, and restoration efforts in the North Atlantic.
Grinyó, J., Aguzzi, J., Kenchington, E., Costa, C., Hanz, U., & Mienis, F. (2023). Occurrence and behavioral rhythms of the endangered Acadian redfish (Sebastes fasciatus) in the Sambro Bank (Scotian Shelf). Frontiers in Marine Science, 10, 1158283.
Corbera, G., Lo Iacono, C., Simarro, G., Grinyó, J., Ambroso, S., Huvenne, V. A., Mienis, F., Carreiro-Silva, M., Martin, I., Mano, B., Orejas, C., Larsson, A., Hennige, S., & Gori, A. (2022). Local-scale feedbacks influencing cold-water coral growth and subsequent reef formation. Scientific Reports, 12(1), 20389.
Four additional articles are in different stages of development, one of which has already been submitted to a peer review journal while the others are in different stages of development.
Grinyó, J., Aguzzi, J., Ortensi, L., Kenchington, E., Kenchington, T., Violino, S., Hanz, U., Santín, A., Nattkemper, T.W. & Mienis, F. (Submitted September 2023) What glass sponges do when no one is looking? Vazella pourtalesii phenology: responses to sediment deposition, passive movement, and contracting behavior. Deep-Sea Research Part I.
Grinyó, J., Aguzzi, J., Garcia, R., Ruscio, F., Kenchington, E., Canepa, A., Costa, C., Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Temporal dynamics of megabenthis species on a Vazella pourtalesii sponge ground.
Grinyó, J., Aguzzi, J., Hassan., A., Saha, A., Canepa, A., Garcia, R., Ruscio, F. Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Cold water community dynamics in a Desmophyllum pertusum reef on the Norwegian continental shelf.
Grinyó, J., Aguzzi, J., Hassan., A., Saha, A., Garcia, R., Ruscio, F. Hanz, U., Nattkemper, T.W. & Mienis, F. (in prep) Benthic storm effects on several deep-sea vulnerable marine ecosystems on the North Atlantic.
The CWCC-Dynamics results will be useful to identify the vulnerability of cold-water coral communities to environmental change and apply this knowledge to maximize the protection, management, and restoration efforts in the North Atlantic.