Effects of salinity and temperature on the recruitment of Aurelia coerulea planulae

ABSTRACT

The recruitment of scyphomedusae planulae to the benthic polyp stage is important for population size and may be affected under projected climate change scenarios. In a laboratory study, we determined the combined effects of elevated temperature and reduced salinity on the behaviour, survival and settlement of Aurelia coerulea planulae. Three temperature levels (21, 24 and 27°C) and two salinity levels (31 and 22) were used. Reduced salinity had a significant negative effect on the swimming behaviour and settlement of A. coerulea planulae. The planulae moved quickly and preferred to settle under ambient salinity conditions. The settlement rate of A. coerulea planulae was high during the current ambient summer temperature (24°C), and elevated temperature increased the mortality rate and reduced their settlement rate. A. coerulea planulae were significantly smaller under the combined conditions of elevated temperature and reduced salinity. Our study provides information on the response of A. coerulea planulae to temperature and salinity, which is helpful for understanding how environmental factors will influence the recruitment dynamics of A. coerulea.

SUBJECT EDITOR:

• Stefania Puce

KEYWORDS:

• Jellyfish blooms
• global warming
• hyposaline conditions
• larval behaviour

Acknowledgements

Z.J.D. gratefully acknowledges the visiting scholarship program from China Scholarship Council and Dr. Kylie Pitt at Griffith University as host for the visit.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China (No. 41576152) and Science and Technology Service Network Initiative (STS) Project (No. KFJ-STS-ZDTP-023).