Dissolved histamine: a potential habitat marker promoting settlement and metamorphosis in sea urchin larvae

Abstract

Many species of marine invertebrate larvae settle and metamorphose in response to chemicals produced by organisms associated with the adult habitat, and histamine is a cue for larvae of the sea urchin Holopneustes purpurascens. This study investigated the effect of histamine on larval metamorphosis of six sea urchin species. Histamine induced metamorphosis in larvae of three lecithotrophic species (H. purpurascens, Holopneustes inflatus and Heliocidaris erythrogramma) and in one planktotrophic species (Centrostephanus rodgersii). Direct comparisons of metamorphic rates of lecithotrophic and planktotrophic larvae in assays cannot be made due to different proportions of larvae being competent. Histamine (10 μM) induced metamorphosis in 95% of larvae of H. purpurascens and H. inflatus after 1 h, while the coralline alga Amphiroa anceps induced metamorphosis in 40-50% of these larvae. Histamine (10 μM) and A. anceps induced 40 and 80% metamorphosis, respectively, in the larvae of H. erythrogramma after 24 h. Histamine (10 μM) and the coralline alga Corallina sp. induced 30 and 70% metamorphosis, respectively, in the larvae of C.rodgersii after 24 h. No metamorphosis of any larval species occurred in seawater controls. Larvae of two planktotrophic species (Tripneustes gratilla and Heliocidaris tuberculata) did not metamorphose in response to histamine. Seagrasses, the host plants of H. inflatus, induced rapid metamorphosis in larvae of the two Holopneustes species, and several algae induced metamorphosis in C. rodgersii larvae. Histamine leaching from algae and seagrasses may act as a habitat marker and metamorphic cue for larvae of several ecologically important sea urchin species.

Increasing the stocking density in Paracentrotus lividus larviculture: Effects on survival and metamorphosis rates

“…fragments in a mortar and used the obtained solution (GUS) as metamorphosis inducing factor. The presence of inducing factors in the GUS is also proven by the absence of metamorphosis in control samples (FSW), consistently with what is reported for P. lividus and other sea urchin species (Swanson et al, ; De La Uz et al, ).…”

“…As sea water conditioned by the presence of conspecific adult specimens fed on Ulva spp. has been found to induce metamorphosis in P. lividus larvae (Gosselin & Jangoux, ), in our previous experiments (Carbonara et al, ) we assumed that grazed algal fragments release dissolved chemical cues, in accordance with what reported for other sea urchin species (Swanson et al, ). Therefore, in order to mimic the decomposing algal conditions arising from the sea urchins’ grazing activity, we ground Ulva spp.…”

“…Larval metamorphosis success may be highly variable also depending on the settlement inducers (Mos et al, ; De La Uz et al, ). Sea urchin larvae have been found to settle and metamorphose in response to a variety of environmental factors, including the presence of macroalgae, microbial or diatom‐based biofilms and conspecific adults, as the bioactive compounds triggering metamorphosis may be released from algae or from their epiphytic biofilm (Dworjanyn & Pirozzi, ; Mos et al, ; Swanson et al, ; De La Uz et al, ). As sea water conditioned by the presence of conspecific adult specimens fed on Ulva spp.…”

“…FSW was used as a control for the measurement of spontaneous metamorphosis, i.e. not depending on the presence of the inducing factor but on the FWS itself or as a consequence of a drastic reduction in larval selectivity (Swanson et al, ; Swanson, Marshall, & Steinberg, ; De La Uz et al, ).…”

Population biology and recruitment of a vulnerable sea cucumber, Stichopus herrmanni, on a protected reef

“…This leeward habitat is characteristic of shallow inter‐tidal consolidated reef of corals and CCA. It is well known that CCA and associated biofilms trigger settlement in sea cucumber and other echinoderm larvae (Ramofafia et al., ; Dworjanyn & Pirozzi, ; Swanson et al., ), corals (Heyward & Negri, ; Harrington, Fabricius, De'ath, & Negri, ; Price, ) and molluscs (Roberts, Kaspar, & Barker, ; Williams, Craigie, Yeates, & Degnan, ). However, studies on the settlement preferences of sea cucumber larvae are scarce (Mercier, Battaglene, & Hamel, ).…”