[en] Mesophotic Coral Ecosystems, the deeper
part of coral reefs (below −30/40 m), remain
largely unexplored mainly because difficult
to access by humans. In this study, fish
sounds were used as a proxy to study
Polynesian mesophotic coral reefs. The aim
of the study was to determine how the
acoustic fish biodiversity varied depending
on the depth and the type of island (atoll vs.
high island), two features known to impact
species richness and diversity. The link
between benthic cover and both the acoustic
α-diversity and acoustic fish community
composition was established at −20, −60
and −120 m in three atolls and three high
islands of French Polynesia. More than 45
different fish sound types were described.
In most islands, acoustic α-diversity
(Shannon index based on sound types)
decreased between −20 and −60 m but not
between −60 and −120 m supporting the
existence of a transition zone between two
distinct fish communities. The highest
similarities between acoustic communities
were found between −60 and −120 m, the
lowest between −20 and −120 m. Overall,
acoustic community composition was
mainly driven by depth likely due to benthic
coral cover differences, and to a lesser
extent, by the type of island. These results
show fish sounds exhibit a bathymetric
stratification. Moreover, differences can
reflect different habitat features. It opens
new perspectives in the study and
monitoring of mesophotic coral ecosystems
using passive acoustics.
Research Center/Unit :
FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
Disciplines :
Zoology
Author, co-author :
Raick, Xavier ; Université de Liège - ULiège > Freshwater and OCeanic science Unit of reSearch (FOCUS)
Lucia, Di Iorio
Cédric, Gervaise
Laetitia, Hédouin
Under The Pole Consortium
Gonzalo, Pérez-Rosales
Héloïse, Rouzé
Bertucci, Frédéric ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Morphologie fonctionnelle et évolutive
Parmentier, Eric ; Université de Liège - ULiège > Freshwater and OCeanic science Unit of reSearch (FOCUS) ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Morphologie fonctionnelle et évolutive
Language :
English
Title :
Passive acoustic monitoring of fish diversity in mesophotic coral ecosystems, potential global-change refuges
Publication date :
29 April 2022
Event name :
BIODIVERSITY 2022 « Biodiversity in a rapidly changing world »
Event organizer :
Biodiversity Research Centre, UCLouvain
Event place :
Louvain-la-Neuve, Belgium
Event date :
28/04/2022-29/04/2022
Audience :
International
Peer reviewed :
Peer reviewed
References of the abstract :
Mesophotic Coral Ecosystems, the deeper
part of coral reefs (below −30/40 m), remain
largely unexplored mainly because difficult
to access by humans. In this study, fish
sounds were used as a proxy to study
Polynesian mesophotic coral reefs. The aim
of the study was to determine how the
acoustic fish biodiversity varied depending
on the depth and the type of island (atoll vs.
high island), two features known to impact
species richness and diversity. The link
between benthic cover and both the acoustic
α-diversity and acoustic fish community
composition was established at −20, −60
and −120 m in three atolls and three high
islands of French Polynesia. More than 45
different fish sound types were described.
In most islands, acoustic α-diversity
(Shannon index based on sound types)
decreased between −20 and −60 m but not
between −60 and −120 m supporting the
existence of a transition zone between two
distinct fish communities. The highest
similarities between acoustic communities
were found between −60 and −120 m, the
lowest between −20 and −120 m. Overall,
acoustic community composition was
mainly driven by depth likely due to benthic
coral cover differences, and to a lesser
extent, by the type of island. These results
show fish sounds exhibit a bathymetric
stratification. Moreover, differences can
reflect different habitat features. It opens
new perspectives in the study and
monitoring of mesophotic coral ecosystems
using passive acoustics.
