Macartney et al. 2020

scientific article | Coral Reefs

Trophodynamics of the sclerosponge Ceratoporella nicholsoni along a shallow to mesophotic depth gradient

Macartney KJ, Pankey MS, Slattery M, Lesser MP


The sclerosponge Ceratoporella nicholsoni is a hyper-calcifying high microbial abundance sponge. This sponge has been observed at high densities throughout the Caribbean in the mesophotic zone (30–150 m), as well as cryptic environments in shallow (< 30 m) depths. Given the densities of this sponge, it could play an important role in the cycling of inorganic and organic sources of carbon and nitrogen at mesophotic depths. Additionally, there is broad interest in this sponge as a tool for paleobiology, paleoclimatology and paleoceanography. As a result, it is increasingly important to understand the ecology of these unique sponges in the underexplored Caribbean mesophotic zone. Here we show that this sponge increases in abundance from shallow depths into the mesophotic zone of Grand Cayman Island. We observed no significant differences in the stable isotope signatures of δ15N and δ13C of sponge tissue between depths. A predictive model of sponge diet with increasing depth shows that these sponges consume dissolved organic matter of algal and coral origin, as well as the consumption of particulate organic matter consistent with the interpretation of the stable isotope data. The taxonomic composition of the sclerosponge microbiome was invariant across the shallow to mesophotic depth range but did contain the Phylum Chloroflexi, known to degrade a variety of dissolved organic carbon sources. These data suggest that the depth distribution of this sponge may not be driven by changes in trophic strategy and is potentially regulated by other biotic or abiotic factors.

Behind the science
Depth range
10- 100 m

Mesophotic “mentions”
53 x (total of 6044 words)

* Presents original data
* Focused on 'mesophotic' depth range
* Focused on 'mesophotic coral ecosystem'

Molecular ecology

Bacteria and Archaea
Porifera (Sponges)

Cayman Islands

SCUBA (open-circuit or unspecified)

Author profiles