title: Quantification of coral sperm collected during a synchronous spawning event.
abstract: Most studies of coral reproductive biology to date have focused on oocyte numbers and sizes. Only one (ex situ) study has enumerated sperm numbers, even though these data have multiple potential applications. We quantified total coral sperm and eggs per gamete bundle collected from six species in situ during a synchronous spawning event in Singapore. Egg-sperm bundles were captured midwater as they floated towards the surface after being released by the colony. For each sample, a semi-transparent soft plastic bottle was squeezed and released to create a small suction force that was used to 'catch' the bundles. This technique provided several advantages over traditional methods, including low cost, ease of use, no diving prior to the night of collection needed, and the ability to target specific areas of the colony. The six species sampled were Echinophyllia aspera, Favites abdita, F. chinensis, Merulina ampliata, M. scabricula and Platygyra pini. The mean number of sperm packaged within one egg-sperm bundle ranged from 2.04 × 10(6) to 1.93 × 10(7). The mean number of eggs per egg-sperm bundle ranged from 26.67 (SE ± 3.27) to 85.33 (SE ± 17.79). These data are critical for fertilisation success models, but the collection technique described could also be applied to studies requiring in situ spawning data at the polyp level.
authors.affiliation: Department of Biological Sciences, National University of Singapore , Singapore.
authors.forename: Aaron
authors.initials: A
authors.lastname: Teo
authors.affiliation: SECORE International , Johor , Malaysia.
authors.forename: James R
authors.initials: JR
authors.lastname: Guest
authors.affiliation: Tropical Marine Science Institute, National University of Singapore, Singapore; St John's Island Marine Laboratory, National University of Singapore, Singapore.
authors.forename: Mei Lin
authors.initials: ML
authors.lastname: Neo
authors.affiliation: Tropical Marine Science Institute, National University of Singapore , Singapore.
authors.forename: Kareen
authors.initials: K
authors.lastname: Vicentuan
authors.affiliation: Department of Biological Sciences, National University of Singapore , Singapore.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Todd
keywords: Coral; Eggs; Gametes; Model; Reproduction; Sperm