An investigation on the impact of substrate type, temperature, and iodine on moon jellyfish production.

Jellyfish are a popular public aquarium species, however, their collection from natural populations is undesirable due to impact on species abundance and bycatch. Thus, a sustainable supply of jellyfish bred in-house would be highly desirable. Here we describe an investigation into developing a sustainable moon jellyfish, Aurelia aurita, breeding program by determining the impact of substrate type on reattachment of polyps and the influence of iodine and temperature on strobilation and ephyra production. To test whether reattachment and growth of moon jellyfish polyps are influenced by substrate type polyps were provided with anthropogenic and natural substrates after being dislodged in experimental aquaria. Polyps selectively re-attached to plastics rather than natural materials. However, polyp growth was similar on all tested substrates. We tested whether cooling and addition of iodine affected strobilation. A period of cooling of around 10 °C while also introducing soluble iodine to the polyps enhanced strobilation rate. This method produced ephyra at a reliable rate in captivity negating the need for collection of wild individuals providing a supply of individuals for exhibit and for conservation research within a public aquarium. These results demonstrate that plastics should be adopted as an easier to colonize substrate and the use of cooling with iodine addition can enhance sustainable breeding protocols of moon jellyfish and may be relevant to the production of comparable jellyfish species.