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Title: Removal of detritivore sea cucumbers from reefs increases coral disease
Abstract

Coral reefs are in global decline with coral diseases playing a significant role. This is especially true for Acroporid corals that represent ~25% of all Pacific coral species and generate much of the topographic complexity supporting reef biodiversity. Coral diseases are commonly sediment-associated and could be exacerbated by overharvest of sea cucumber detritivores that clean reef sediments and may suppress microbial pathogens as they feed. Here we show, via field manipulations in both French Polynesia and Palmyra Atoll, that historically overharvested sea cucumbers strongly suppress disease among corals in contact with benthic sediments. Sea cucumber removal increased tissue mortality ofAcropora pulchraby ~370% and colony mortality by ~1500%. Additionally, farmerfish that killAcropora pulchrabases to culture their algal gardens further suppress disease by separating corals from contact with the disease-causing sediment—functioning as mutualists rather than parasites despite killing coral bases. Historic overharvesting of sea cucumbers increases coral disease and threatens the persistence of tropical reefs. Enhancing sea cucumbers may enhance reef resilience by suppressing disease.

 
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Award ID(s):
1947522 2224354
NSF-PAR ID:
10492577
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Communications
Volume:
15
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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