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,...

Herbivorous fish maintain a critical ecosystem function on coral reefs by grazing algae and maintaining highly productive algal turf assemblages. Current paradigms implicate habitat complexity, predation and primary productivity as major drivers of the distribution and abundance of herbivorous fish, yet little is known about the relative contribution of these factors. Here, we compare bottom-up and top-down drivers of notional herbivore assemblages across an environmental gradient of wave exposure in the Palau archipelago. We surveyed...

Trait diversity, a key component of biodiversity, mediates many essential ecosystem functions and services. However, the mechanisms behind such relationships at large spatial scales are not fully understood. Here we adopt the functional biogeography approach to investigate how the size composition of phytoplankton communities relates to primary production and export production along a broad latitudinal gradient. Using in situ phytoplankton size distribution data and a trait-based model, we find an increase in the average phytoplankton...

Population declines in shark species have been reported on local and global scales, with overfishing, habitat destruction and climate change posing severe threats. The lack of species-specific baseline data on ecology and distribution of many sharks, however, makes conservation measures challenging. Here we present a fisheries-independent shark survey from the Fiji Islands, where scientific knowledge on locally occurring elasmobranchs is largely still lacking despite the location’s role as a shark hotspot in the Pacific. Juvenile...

Corals and macroalgae release large quantities of dissolved organic matter (DOM), one of the largest sources of organic matter produced on coral reefs. By rapidly taking up DOM and transforming it into particulate detritus, coral reef sponges are proposed to play a key role in transferring the energy and nutrients in DOM to higher trophic levels via the recently discovered sponge loop. DOM released by corals and algae differs in quality and composition, but the...

1. With the increasing anthropogenic impacts on fish habitats, it has become more important to understand which primary resources sustain fish populations. This resource utilization can differ between fish life stages and individuals can migrate between habitats in search of resources. Such lifetime information is difficult to obtain due to the large spatial and temporal scales of fish behaviour. The otolith organic matrix has the potential to indicate this resource utilization and migration with δ13C...