Vol. 61, 2022
Transplantation Tests of
Precious Coral Fragments Using Small-sized Artificial Substratum
Tatsuki Koido1,*, Sho Toshino1,
Fujio Kumon2,3, Shu Nakachi4, Noriyoshi Yoshimoto5,
and Takuma Mezaki1
Biological Research Foundation, 560 Nishidomari, Otsuki, Kochi
788-0333, Japan. *Correspondence: E-mail: firstname.lastname@example.org
E-mail: email@example.com (Toshino); firstname.lastname@example.org (Mezaki)
2Faculty of Science, Shinshu University, 3-1-1 Asahi,
Matsumoto 390-8621, Japan. E-mail: email@example.com (Kumon)
3Center for Advanced Marine Core Research, Kochi University, 200
Monobe-Otsu, Nankoku, Kochi, 783-8502, Japan. E-mail:
4Natural History Lab, Suogata, Otsuki, Kochi 788-0313, Japan. E-mail:
5Non-Government Organization of the Precious Coral Protection and
Development Association, 5F, Kearney-Place Bldg., 1-3-20 Honmachi,
Kochi 788-0870, Japan. E-mail: firstname.lastname@example.org (Yoshimoto)
Received 15 February 2022 / Accepted
30 May 2022
Communicated by Nozawa Yoko
the Roman era, precious corals have been used to make ornaments
worldwide, and their demand has recently increased. As a basic study
for artificial cultivation, we transplanted Corallium japonicum
fragments. In 2016 and 2017, 132 fragments approximately 3–5 cm in
length were attached to small-sized artificial substratums using marine
epoxy on land. These artificial substratums, acting as transplant
substrates, were then transported and sunk to a depth approximately 100
m off the coast of Otsuki Town and Tosashimizu City, Kochi Prefecture,
where precious corals once flourished. From six months to three years
post-submersion, we successfully recovered the transplanted substrates
and found a total of 107 fragments (81%). We confirmed that 106 of
these fragments were alive 177 to 936 days after transplantation.
Although we could not measure growth rates due to the initial damage
caused by the transplantation, we observed growth of coenenchyme
tissues, new polyps and new branches in the 104 surviving fragments.
This result suggests there is great potential to artificially multiply
precious corals, which could aid in the development of a sustainable
precious coral industry.
Key words: Coralliidae, Corallium japonicum, Mesophotic
zone, Kochi, Japan.
Koido T, Toshino S, Kumon F, Nakachi S, Yoshimoto N, Mezaki T. 2022.
Transplantation tests of precious coral fragments using small-sized
artificial substratum. Zool Stud 61:46.