Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis
During a survey of the Håkon Mosby mud volcano (HMMV), located on the Bear Island fan in the southwest Barents Sea at ∼1250 m water depth, different habitats inside the volcano caldera and outside it were photographed using a towed camera platform, an Ocean Floor Observation System (OFOS). Three tra...
Published in: | Biogeosciences |
---|---|
Main Authors: | , , , , |
Format: | Text |
Language: | English |
Published: |
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/bg-10-3359-2013 https://www.biogeosciences.net/10/3359/2013/ |
id |
ftcopernicus:oai:publications.copernicus.org:bg18008 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:bg18008 2023-05-15T15:38:53+02:00 Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis Rybakova (Goroslavskaya), E. Galkin, S. Bergmann, M. Soltwedel, T. Gebruk, A. 2018-09-27 application/pdf https://doi.org/10.5194/bg-10-3359-2013 https://www.biogeosciences.net/10/3359/2013/ eng eng doi:10.5194/bg-10-3359-2013 https://www.biogeosciences.net/10/3359/2013/ eISSN: 1726-4189 Text 2018 ftcopernicus https://doi.org/10.5194/bg-10-3359-2013 2019-12-24T09:55:20Z During a survey of the Håkon Mosby mud volcano (HMMV), located on the Bear Island fan in the southwest Barents Sea at ∼1250 m water depth, different habitats inside the volcano caldera and outside it were photographed using a towed camera platform, an Ocean Floor Observation System (OFOS). Three transects were performed across the caldera and one outside, in the background area, each transect was ∼2 km in length. We compared the density, taxa richness and diversity of nonsymbiotrophic megafauna in areas inside the volcano caldera with different bacterial mat and pogonophoran tubeworm cover. Significant variations in megafaunal composition, density and distribution were found between considered areas. Total megafaunal density was highest in areas of dense pogonophoran populations (mean 52.9 ind. m −2 ) followed by areas of plain light-coloured sediment that were devoid of bacterial mats and tube worms (mean 37.7 ind. m −2 ). The lowest densities were recorded in areas of dense bacterial mats (mean ≤1.4 ind. m −2 ). Five taxa contributed to most of the observed variation: the ophiuroid Ophiocten gracilis , lysianassid amphipods, the pycnogonid Nymphon macronix , the caprellid Metacaprella horrida and the fish Lycodes squamiventer . In agreement with previous studies, three zones within the HMMV caldera were distinguished, based on different habitats and megafaunal composition: "bacterial mats", "pogonophoran fields" and "plain light-coloured sediments". The zones were arranged almost concentrically around the central part of the caldera that was devoid of visible megafauna. The total number of taxa showed little variation inside (24 spp.) and outside the caldera (26 spp.). The density, diversity and composition of megafauna varied substantially between plain light-coloured sediment areas inside the caldera and the HMMV background. Megafaunal density was lower in the background (mean 25.3 ind. m −2 ) compared to areas of plain light-coloured sediments inside the caldera. So the effect of the mud-volcano environment on benthic communities is expressed in increasing of biomass, changing of taxa composition and proportions of most taxonomic groups. Text Barents Sea Bear Island Copernicus Publications: E-Journals Barents Sea Bear Island ENVELOPE(-67.250,-67.250,-68.151,-68.151) Biogeosciences 10 5 3359 3374 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
During a survey of the Håkon Mosby mud volcano (HMMV), located on the Bear Island fan in the southwest Barents Sea at ∼1250 m water depth, different habitats inside the volcano caldera and outside it were photographed using a towed camera platform, an Ocean Floor Observation System (OFOS). Three transects were performed across the caldera and one outside, in the background area, each transect was ∼2 km in length. We compared the density, taxa richness and diversity of nonsymbiotrophic megafauna in areas inside the volcano caldera with different bacterial mat and pogonophoran tubeworm cover. Significant variations in megafaunal composition, density and distribution were found between considered areas. Total megafaunal density was highest in areas of dense pogonophoran populations (mean 52.9 ind. m −2 ) followed by areas of plain light-coloured sediment that were devoid of bacterial mats and tube worms (mean 37.7 ind. m −2 ). The lowest densities were recorded in areas of dense bacterial mats (mean ≤1.4 ind. m −2 ). Five taxa contributed to most of the observed variation: the ophiuroid Ophiocten gracilis , lysianassid amphipods, the pycnogonid Nymphon macronix , the caprellid Metacaprella horrida and the fish Lycodes squamiventer . In agreement with previous studies, three zones within the HMMV caldera were distinguished, based on different habitats and megafaunal composition: "bacterial mats", "pogonophoran fields" and "plain light-coloured sediments". The zones were arranged almost concentrically around the central part of the caldera that was devoid of visible megafauna. The total number of taxa showed little variation inside (24 spp.) and outside the caldera (26 spp.). The density, diversity and composition of megafauna varied substantially between plain light-coloured sediment areas inside the caldera and the HMMV background. Megafaunal density was lower in the background (mean 25.3 ind. m −2 ) compared to areas of plain light-coloured sediments inside the caldera. So the effect of the mud-volcano environment on benthic communities is expressed in increasing of biomass, changing of taxa composition and proportions of most taxonomic groups. |
format |
Text |
author |
Rybakova (Goroslavskaya), E. Galkin, S. Bergmann, M. Soltwedel, T. Gebruk, A. |
spellingShingle |
Rybakova (Goroslavskaya), E. Galkin, S. Bergmann, M. Soltwedel, T. Gebruk, A. Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
author_facet |
Rybakova (Goroslavskaya), E. Galkin, S. Bergmann, M. Soltwedel, T. Gebruk, A. |
author_sort |
Rybakova (Goroslavskaya), E. |
title |
Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
title_short |
Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
title_full |
Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
title_fullStr |
Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
title_full_unstemmed |
Density and distribution of megafauna at the Håkon Mosby mud volcano (the Barents Sea) based on image analysis |
title_sort |
density and distribution of megafauna at the håkon mosby mud volcano (the barents sea) based on image analysis |
publishDate |
2018 |
url |
https://doi.org/10.5194/bg-10-3359-2013 https://www.biogeosciences.net/10/3359/2013/ |
long_lat |
ENVELOPE(-67.250,-67.250,-68.151,-68.151) |
geographic |
Barents Sea Bear Island |
geographic_facet |
Barents Sea Bear Island |
genre |
Barents Sea Bear Island |
genre_facet |
Barents Sea Bear Island |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-10-3359-2013 https://www.biogeosciences.net/10/3359/2013/ |
op_doi |
https://doi.org/10.5194/bg-10-3359-2013 |
container_title |
Biogeosciences |
container_volume |
10 |
container_issue |
5 |
container_start_page |
3359 |
op_container_end_page |
3374 |
_version_ |
1766370292642349056 |