European native oyster reef ecosystems are universally collapsed

Philine S.E. zu Ermgassen*, Hannah McCormick, Alison Debney, José M. Fariñas-Franco, Celine Gamble, Chris Gillies, Boze Hancock, Ane T. Laugen, Stéphane Pouvreau, Joanne Preston, William G. Sanderson, Åsa Strand, Ruth H. Thurstan

*Corresponding author for this work

Research output: Contribution to journalLiterature reviewpeer-review

6 Downloads (Pure)

Abstract

Oyster reefs are often referred to as the temperate functional equivalent of coral reefs. Yet evidence for this analogy was lacking for the European native species Ostrea edulis. Historical data provide a unique opportunity to develop a robust definition for this ecosystem type, confirm that O. edulis are large-scale biogenic reef builders, and assess its current conservation status. Today, O. edulis occur as scattered individuals or, rarely, as dense clumps over a few m2. Yet historically, O. edulis reef ecosystems persisted at large scales (several km2), with individual reefs within the ecosystems present at the scale of several hectares. Using the IUCN Red List of Ecosystems Framework, we conclude the European native oyster reef ecosystem type is collapsed under three of five criteria (A: reduction in geographic distribution, B: restricted geographic range, and D: disruption of biotic processes and interactions). Criterion C (environmental degradation) was data deficient, and Criterion E (quantitative risk analysis) was not completed as the ecosystem was already deemed collapsed. Our assessment has important implications for conservation policy and action, highlighting that the habitat definitions on which conservation policies are currently based reflect a highly shifted baseline, and that the scale of current restoration efforts falls far short of what is necessary for ecosystem recovery.

Original languageEnglish
Article numbere13068
Number of pages12
JournalConservation Letters
Volume18
Issue number1
Early online date4 Dec 2024
DOIs
Publication statusPublished - 1 Jan 2025

Keywords

  • habitat restoration
  • historical ecology
  • IUCN Ecosystem Red List
  • Ostrea edulis
  • shellfish reef
  • shifted baseline
  • threats

Fingerprint

Dive into the research topics of 'European native oyster reef ecosystems are universally collapsed'. Together they form a unique fingerprint.

Cite this