Vol. 60, 2021

(update: 2021.05.20; 07.13)
 

Seasonal Growth of the Purple Sea Urchin Heliocidaris crassispina Revealed by Sequential Fluorochrome Tagging

Juan Diego Urriago Suarez^1,2,3, Jane C.Y. Wong², Gilbert Lui⁴, Clement P. Dumont⁵, Jian-Wen Qiu^2,3, and Monthon Ganmanee^1,*

¹Department of Animal Production Technology and Fisheries, Faculty of Agricultural Technology, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand. *Correspondence: E-mail: monthon.ga@kmitl.ac.th (Ganmanee). Tel: +6623298140.
E-mail: urriago@gmail.com (Suarez)
²Department of Biology, Hong Kong Baptist University, Hong Kong, China. E-mail: chingyanw11@gmail.com (Wong)
³Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China. E-mail: qiujw@hkbu.edu.hk (Qiu)
⁴Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China. E-mail: csglui@gmail.com (Lui)
⁵School of Biological Sciences, The University of Hong Kong, Hong Kong, China. E-mail: clement@asc.run (Dumont)

Received 8 January 2020 / Accepted 6 May 2021
Communicated by Yoko Nozawa

Many studies have applied fluorochrome tagging to examine the growth of animals with calcified skeletons, but most of them have used only a single tag to determine the annual growth rate. We used sequential fluorochrome tagging to study the seasonal growth of the purple sea urchin Heliocidaris crassispina in Hong Kong waters from February 2012 to February 2013. Sea urchins ranging from 18.9 to 42.7 mm in test diameter had a yearly growth from 0.6 to 13.0 mm. During that year, the sea urchins grew from 0.6 to 5.0 mm in test diameter during the first six months, and from 0.4 to 10.2 mm in test diameter in the second six months. The seasonal differences in growth were confirmed using the von Bertalanffy model. The growth was clear for young sea urchins, especially for individuals less than 5 years old, but was not evident for sea urchins older than 7 years. The seasonal differences in growth were probably related to the reproductive cycle and the seasonal differences in environmental conditions. Our empirical results provide the first evidence of seasonal changes in growth for H. crassispina, demonstrating the usefulness of sequential fluorochrome tagging in studying the growth of sea urchins in the field. We also identify the problem of low recovery of tagged individuals and provide recommendations to improve the tagging procedure.

Key words: Calcein, Calcein blue, Fluorochrome, Seasonal growth model, Sea urchin, Tagging.

Citation: Suarez JDU, Wong JCY, Lui G, Dumont CP, Qiu JW, Ganmanee M. 2021. Seasonal growth of the purple sea urchin Heliocidaris crassispina revealed by sequential fluorochrome tagging. Zool Stud 60:38. doi:10.6620/ZS.2021.60-38.

Supplementary Materials: Fig. S1 | Fig. S2 | DataSet S1