Interaction of conspecific cues in Balanus amphitrite Darwin (Cirripedia) settlement assays: Continued argument for the single-larva assay
Titel:
Interaction of conspecific cues in Balanus amphitrite Darwin (Cirripedia) settlement assays: Continued argument for the single-larva assay
Auteur:
Elbourne, Peter D. Veater, Robert A. Clare, Anthony S.
Verschenen in:
Biofouling
Paginering:
Jaargang 24 (2008) nr. 2 pagina's 87-96
Jaar:
2008
Inhoud:
Gregariousness in marine invertebrate larvae is an important regulator of benthic community structure. Previous laboratory settlement assays employing Balanus amphitrite Darwin cyprids found gregarious effects with as few as 3 larvae well-1, together with modulation of such effects by chemical cues. Here, the relationship between settlement rate and larval density was rigorously tested through a fully randomised design. Seawater conditioned with adult B.amphitrite was tested alongside unconditioned seawater to determine the effect of a conspecific cue on gregarious interactions. Gregarious effects were detected in both conditioned and unconditioned seawater at ≤4 larvae well-1. In untreated seawater, settlement rate increased linearly with larval density, levelling off at densities of ≥10 larvae well-1. In conditioned seawater, settlement induction was observed at ≤4 larvae well-1, switching to inhibition at 6, 8 and 10 larvae well-1, before asymptoting at the highest densities tested. These results advocate the use of individual larvae in laboratory assays that investigate factors stimulating barnacle settlement.