The vermetid gastropodDendropoma maximumreduces coral growth and survival

Abstract

These authors contributed equally to this work.Coral reefs are one of the most diverse systems on the planet; yet, only a small fraction of coral reef species have attracted scientific study. Here, we document strong deleterious effects of an often overlooked species-the vermetid gastropod, Dendropoma maximum-on growth and survival of reef-building corals. Our surveys of vermetids on Moorea (French Polynesia) revealed a negative correlation between the density of vermetids and the per cent cover of live coral. Furthermore, the incidence of flattened coral growth forms was associated with the presence of vermetids. We transplanted and followed the fates of focal colonies of four species of corals on natural reefs where we also manipulated presence/absence of vermetids. Vermetids reduced skeletal growth of focal corals by up to 81 per cent and survival by up to 52 per cent. Susceptibility to vermetids varied among coral species, suggesting that vermetids could shift coral community composition. Our work highlights the potential importance of a poorly studied gastropod to coral dynamics.

Vermetid gastropods mediate within-colony variation in coral growth to reduce rugosity

“…colonies with vermetids often appear locally flattened ( Fig. 1b; see also Shima et al 2010). In contrast, massive Porites spp.…”

“…Previous experiments (Colgan 1985;Shima et al 2010Shima et al , 2013 indicate that the vermetid gastropod, Ceraesignum maximum (formerly Dendropoma maximum; see Golding Abstract Intraspecific variation in coral colony growth forms is common and often attributed to phenotypic plasticity. The ability of other organisms to induce variation in coral colony growth forms has received less attention, but has implications for both taxonomy and the fates of corals and associated species (e.g.…”

“…et al 2014 for recent taxonomic revision), reduces the growth and survival of several species of corals and may have the ability to dramatically alter coral growth forms (Colgan 1985;Zvuloni et al 2008;Shima et al 2010). C. maximum produces pelagic larvae (Phillips and Shima 2010) that settle and permanently attach to bare substrate (Phillips et al 2014).…”

Assessing coral health in Moorea, French Polynesia after a regional die-off of the coral antagonist, Dendropoma maxima

“…A well-documented interaction exists between Porites corals and the vermetid gastropod 41 "worm," Dendropoma maxima, on the fringing and back reefs of Mo'orea, French Polynesia 42 (Shima and Osenberg and Stier, 2010). Vermetid worms anchor themselves to hard substrate, 43 grow cylindrical shells, and cast mucus nets into the current to capture food particles (Phillips, 44 2011).…”

Variation in the growth and survival of the tropical vermetid gastropod Ceraesignum maximum is driven by size, habitat, and density

“…At first glance, vermetids appear to be minor players in the reef system. However, vermetids can cause growth anomalies in corals (Colgan 1985;Zvuloni et al 2008;Shima et al 2010Shima et al , 2015, reduce coral growth by up to 80 %, and reduce coral survival by ~50 % (Shima et al , 2013Stier et al 2010). Due to differential effects on coral species (which may also be context-dependent, e.g.…”