Gradual and rapid shifts in the composition of assemblages of hydroids (Cnidaria) along depth and latitude in the deep Atlantic Ocean

Details

• Journal Title:
  Journal of Biogeography
• Personal Author:
  Fernandez, Marina O. ; Collins, Allen G. ; Marques, Antonio C.
• NOAA Program & Office:
  NMFS (National Marine Fisheries Service) ; OST (Office of Science and Technology)
• Description:
  Aim
  
  Despite growing knowledge on deep‐sea benthic fauna, patterns of changes in species composition combining both bathymetric and latitudinal variation are still poorly known. In the first synthesis on the beta diversity patterns of assemblages of hydroids across an entire ocean basin, our aim was to infer limits and gradients of species distribution along depth and latitude.
  
  Location
  
  Atlantic Ocean and adjacent polar seas.
  
  Taxon
  
  Hydrozoa.
  
  Methods
  
  Hydroids from 50 to 5,330 m deep were studied primarily based on museum collections. Identifications were made by the authors, improving uniformity within the dataset by avoiding variations in taxonomic interpretation. Data totalled 3,699 records belonging to 432 species, at 1,444 unique sites. Records were assigned to three depth strata (50–200, 201–1,000 and 1,001–5,330 m) and eight latitudinal bands of 20° each, totalling 24 sample areas. We conducted non‐metric multidimensional scaling (NMDS) ordination, clustering and PERMANOVA analyses of species compositions and abundances per area to examine differences and relationships in hydroid assemblages among areas.
  
  Results
  
  Assemblages primarily differentiate between those to the north and south of 40°S, regardless of depth, with southern ones separated between Patagonian and Antarctic. Northwards of 40°S, assemblages differentiate gradually along both depth and latitude, although a faunal turnover occurs at 1,000 m deep. Also, assemblages at 1,001–5,330 m deep tend to be more similar to each other than assemblages at shallower strata, suggesting significant connectivity over great distances in the deep sea. We note the problem of largely unequal hydroid sampling in the Atlantic Ocean across depths and latitudes, especially in the southern hemisphere and below 1,000 m deep.
  
  Main Conclusions
  
  Assemblages of hydroids differentiate gradually along latitude and depth, with more rapid shifts in species composition occurring at 40°S, 60°S and at 1,000 m deep. Greater similarity was found among deeper water assemblages.
  
  
• Keywords:
  Biogeography Hydrozoa Deep-sea Benthos Marine Biogeography
• Source:
  Journal of Biogeography 47(7): 1541-1551, 2020
• DOI:
  https://doi.org/10.1111/jbi.13853
• Document Type:
  Journal Article
• Place as Subject:
  Atlantic Ocean
• Rights Information:
  Accepted Manuscript
• Rights Statement:
  The NOAA IR provides access to this content under the authority of the government's retained license to distribute publications and data resulting from federal funding. While users may legally access this content, the copyright owners retain rights that govern the reproduction, redistribution, and re-use of this work. The user is solely responsible for complying with applicable copyright law.
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:8fa1f0b67b7ef27c27b8f95761b3dfc2847e34ec0811d21acd0a01240ded62d70a288d57a25d35892e6da5938ad425e80f8b064ca1b28186e06536c6fc0b3c84
• Download URL:
  https://repository.library.noaa.gov/view/noaa/29174/noaa_29174_DS1.pdf
• File Type:
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