Darwin Plus SO Red Listing

Red Listing can protect OT marine biodiversity

Start date
20 September, 2021
End date
30 September, 2022

Darwin Plus logo

The IUCN Red List is the international standard for conservation, a crucial tool to communicate threats to species, which can be applied to all species and ecosystems. Molluscs represent a diverse group with commercial and ecological significance in almost all habitats, from reef-forming mussels to pelagic schools of squid. The first Red List for Antarctic and Subantarctic marine molluscs, for the British Antarctic Territory, Falkland Islands, South Georgia and South Sandwich Islands, funded by Darwin Plus,  will provide conservation tools for both these and global UKOTs. The GSGSSI Marine Protected Area includes a few rare endemic species in submarine volcanic areas recently listed as “Least Concern”, explicitly because of the legal protection in place. This reflects the international impact of GSGSSI local conservation measures. Our area-based project will encompass shelf and coastal species at extreme risk from climate change, combining the IUCN Red List protocol with novel trait-based climate change vulnerability assessments. This project will complete assessments for over 100 species at greatest risk and provide training to empower local agencies in all UKOTs to apply Red List criteria. This project will be a critical step in developing prioritisation mechanisms for conservation action in UK overseas territories through area-based conservation.


Molluscs from the Southern Ocean

Marine ecosystems are under increasing pressure from coastal and offshore development, fish, plastic pollution and from climate change causing sea level rise, and increasing wave heights and sea surface temperatures. Examining potential threats to species shared across Antarctic and Subantarctic UKOTs encompasses the impacts of all these issues, as well as the mitigating effects of conservation measures such as the SGSSI Marine Protected Area.

The IUCN Red List of Threatened Species is recognised as the international standard for conservation, guiding environmental actions and sustainable development by identifying species most at risk. It is widely used to track progress towards internationally agreed biodiversity targets (CBD) and identify conservation success (in conjunction with the IUCN Green List). Inclusion on the Red List provides a robust baseline conservation value; re-assessments are done routinely but may be urgently prompted by a change in habitat status. Marine species remain dramatically under-represented in Red List assessments: of 120,000 species assessed to date, only 15% are marine species (mostly fish and seabirds), and only 212 assessed marine species occur in the Southern Ocean.

IUCN Red List of Threatened Species categories (IUCN.org)

Robust Red List assessments are the strongest basis to protect species and their habitats. A lack of assessment may prevent stakeholders from understanding when species are under threat, and when conservation measures are effective. In addition, robust assessments of climate change vulnerability allow the detection of additional conservation priorities under predicted climate change scenarios. These are universal problems applicable to all UKOTs. The proposed project aims to start filling the assessment gap, using marine molluscs in Antarctic and Subantarctic UKOTs as a case study. Molluscs cover the broadest possible range of habitats and lifestyles, and there is a strong Mollusc Working Group established within the IUCN that is a partner on this project. However, our results will be applicable to all species in all UKOTs.


  • Compilation of a complete species list for molluscs in the region and their distributions, starting with a georeferenced database already available and applying further expert quality controls (updating taxonomy, ensuring consistent nomenclature, etc).
  • Completion of formal Red List assessments for species found in the three OT areas and after IUCN quality control checks, publication on the IUCN website (.
  • Producing a simple easy-to-apply roadmap to facilitate future assessments in these and other UKOTs by compiling data relevant to the assessment process in this region. We will document a practical protocol for assessment, streamlined for this region, that can be applied to Southern Ocean molluscs and other marine invertebrates.
  • Hybrid training workshop to include the project partners and additional stakeholders (e.g., Falklands Conservation, Shallow Marine Surveys Group) and any other scientists from other UKOTs und South American countries. The workshop will provide training to any stakeholders willing to take on future additional assessments or re-assessments of any UKOT species, to continue the UKOT Red Listing project beyond the scope of this one-year programme.