Résumé
Determining whether many functionally complementary species or only a
subset of key species are necessary to maintain ecosystem functioning and
services is a critical question in community ecology and biodiversity
conservation. Identifying such key species remains challenging, especially
in the tropics where many species co-occur and can potentially support the
same or different processes. Here, we developed a new community-wide scan
(CWS) approach, analogous to the genome-wide scan, to identify fish
species that significantly contribute, beyond the socio-environmental and
species richness effects, to the biomass and coral cover on Indo-Pacific
reefs. We found that only a limited set of species (51 out of ~400,
approximately 13%), belonging to various functional groups and
evolutionary lineages, are strongly and positively associated with fish
biomass and live coral cover. Many of these species have not previously
been identified as functionally important and thus, may be involved in
unknown, yet important, biological mechanisms that help sustain healthy
and productive coral reefs. CWS has the potential to reveal species that
are key to ecosystem functioning and services and to guide management
strategies as well as new experiments to decipher underlying causal
ecological processes.