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talk · Thursday 24 September · 16:02–⁠16:14 · FORUM

Mapping geographical distributions in the World Register of Marine Species

Serge Gofas · From WDSRPD to GeoSchemes: Recording Biodiversity Distributions for Science and Policy

Recording time 7:49:15–8:02:42Open on Vimeo ↗

Summaries and key moments are machine-produced. Check the recording for the speaker’s exact words.

The short versionA country-aware, hierarchical marine geoscheme will let WoRMS and others record and query distributions consistently, pending a solution for defining spatial units in a TDWG standard.

Overview

What this was about

Serge Gofas explained why WoRMS needed a standard set of marine geounits: species distributions were recorded with haphazard units. Neither EEZs (too uneven) nor Marine Ecoregions of the World (ignoring borders) were adequate, so the TDWG GeoSchemes marine task group published a hierarchical proposal with five oceans, ~200 level-two and 577 level-four units, coastal areas split country-wise and high seas based on Watling et al. He raised the unresolved issue of how to write English 'definitions' required by the TDWG standards specification for spatial units, proposing reference to maps in Marine Regions, and outlined uses including national checklists, cross-checking GBIF/OBIS points and global analysis.

Why it matters. It extends a widely used TDWG geographic standard to the oceans, enabling national marine checklists and literature-based distribution records.

Key ideas

In the room

  • WoRMS is curated by 300+ experts and hosted at VLIZ; its distribution tab suffered from inconsistent geounits.
  • EEZs work for small countries but large or multi-coast countries need subdivision.
  • MEOW ignores country borders, making locality assignment ambiguous.
  • Level one: major oceans; level two: coastal areas by biogeographic region plus high seas; level four: 577 units.
  • High seas use Watling et al. with a 3,500 m threshold between bathyal and abyssal.
  • Unit codes are unique across terrestrial and marine parts and can serve as controlled vocabulary strings.
  • Unit sizes (100,000-500,000 km2) are comparable to five-degree grids.
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Notable moments

In their words

Transcript

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Programme abstract

Mapping geographical distributions in the World Register of Marine Species

Serge Gofas

The World Register of Marine Species (WoRMS) is an authoritative database hosted at the Flanders Marine Institute (VLIZ), aiming to provide a comprehensive list of all marine organisms. Associated information on the species includes “Documented distribution” backed by published sources. Since the beginnings of WoRMS this representation has been hampered by the lack of an agreed set of geounits, of homogeneous extension. For this reason the Geoschemes task group of TDWG was set up to undertake a proposal, which will parallel the current “World Geographic Scheme for Recording Plant Distribution” used on land.

Purposes of this set of geounits is twofold: (1) to provide a sensible visual representation of a species’ range, aso able to handle imprecise country-level records from the old literature and (2) to provide bounding boxes for the retrieval of distribution data and species lists, particularly at the country level.

The countries’ Exclusive Economic Zones (EEZs) were either taken as recording units or subdivided where needed, and the High Seas were subdivided according to physiographical features in the bathyal and abyssal stages respectively. A hierarchical set of five Level-1 units, 26 Level-2 units, 232 Level-3 units and 536 Level-4 units is currently under review. Subdivision of the large or complex EEZs followed Marine Ecoregions of the World or the IHO Limits of Oceans and Seas when appropriate, and existing local schemes were adopted for Europe and Australia. Attempts to distinguish habitats were disregarded in view of the advantages of having a standard representation for all the species: therefore, representing a polygon as a distribution record assumes that the species exists “somewhere” inside, not everywhere.

Submitted to the conference programme before the talk, so the talk itself may differ.