The effects of food and temperature on settlement of Aurelia aurita planula larvae and subsequent somatic growth

Effects of hyposalinity on survival and settlement of moon jellyfish (Aurelia aurita) planulae

“…In this study, A. aurita planulae avoided swimming in the water column, preferring to swim either at the surface near the settlement film or along the bottom of the well. This observation is in accordance with previous descriptions of behavior of planulae of A. aurita from the North Sea (Holst and Jarms, 2007) and is hypothesized to be an adaptive behavior for avoiding turbulence or predation (Webster and Lucas, 2012), or for increasing likelihood of contact with settlement substrates (Holst and Jarms, 2007). The effect of salinity on the geotaxis of planulae is complex; it was negative in 32, 25, and 20, but positive in 15, at least during the first 4 h of exposure.…”

“…Duarte et al, 2012;Vermeij et al, 2006;Webster and Lucas, 2012). This design is often justified on the basis that larvae exhibit high mortality rates, and therefore multiple larvae may be necessary to obtain sufficient results.…”

A matter of tolerance: Distribution potential of scyphozoan polyps in a changing environment

“…Larval settlement and metamorphosis into polyps was still possible after exposure to extreme temperature differences (∆ max = 13°C). Low water temperature (4°C) resulted in an extended planktonic phase until settlement combined with significantly higher settlement rates, as has been documented for planula larvae collected from medusae in southern England (Webster & Lucas, ). A positive correlation between temperature and metabolic rates (Webster & Lucas, ) is supported by increased numbers of settled planula larvae and reduced growth rates of early polyp stages at low temperature.…”

“…Low water temperature (4°C) resulted in an extended planktonic phase until settlement combined with significantly higher settlement rates, as has been documented for planula larvae collected from medusae in southern England (Webster & Lucas, ). A positive correlation between temperature and metabolic rates (Webster & Lucas, ) is supported by increased numbers of settled planula larvae and reduced growth rates of early polyp stages at low temperature. The present results further demonstrate good physiological condition of A. aurita polyps in a wide temperature range (4–15°C), confirming previous observations on negligible effects of changes in water temperature for the survival of benthic scyphozoans (Willcox, Moltschaniwskyj, & Crawford, ).…”

Long-Term Fluctuations in Circalunar Beach Aggregations of the Box Jellyfish Alatina moseri in Hawaii, with Links to Environmental Variability

“…Jellyfish are known to increase growth rates and reach larger adult sizes in response to increased food availability [74], and since body size positively correlates with fecundity in jellyfish, more eggs (and more larvae) are produced when food is readily available [75], [76], potentially increasing larval recruitment [54]. At the same time, increased food availability in the water column can also affect the amount of food reaching the benthos [77], [78], [79], and jellyfish polyps are known to increase budding rates (i.e., asexual production of new polyps) in response to an increase in food supply [80], [81], [82], [83], potentially translating into higher numbers of medusae released via strobilation during periods with high zooplankton biomass compared to years of low zooplankton biomass. In polyps of the box jellyfish A. moseri ( =  A. mordens , [41]) increased feeding frequency resulted in increased budding rates [55], with similar results obtained for a related species [84].…”