Vol. 58, 2019

(update: 2019.07.26; 09.17)
 

Expansion of the Northern Geographical Distribution of Land Hermit Crab Populations: Colonization and Overwintering Success of Coenobita purpureus on the Coast of the Boso Peninsula, Japan

Tetsuya Sanda^1,2, Katsuyuki Hamasaki^1,*, Shigeki Dan¹, and Shuichi Kitada¹

¹Department of Marine Biosciences, Tokyo University of Marine Science and Technology, Konan, Minato, Tokyo 108-8477, Japan. *Correspondence: E-mail: hamak@kaiyodai.ac.jp. E-mail: sdan@kaiyodai.ac.jp (Dan); kitada@kaiyodai.ac.jp (Kitada)
²Present Address: Research Center for Subtropical Fisheries, Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Fukai-Ota, Ishigaki, Okinawa 907-0451, Japan. E-mail: sanda@affrc.go.jp (Sanda)

Received 22 April 2019 / Accepted 22 July 2019
Communicated by Benny K.K. Chan

The present study aimed to elucidate the population dynamics of land hermit crabs on the coast of the Boso Peninsula, Chiba Prefecture, Japan, which is the northern limit of their geographical distribution. We conducted monthly field surveys at four sites from April 2012 to December 2014 and visually searched for crabs. Laboratory experiments were also conducted to evaluate the overwintering ability of two species, Coenobita purpureus and C. rugosus, which were detected during the field surveys; adult crabs and laboratory-raised juveniles were exposed to low-temperature conditions that simulated the in situ temperatures during the early overwintering period. Newly landed juveniles first appeared in August. They were identified as either C. purpureus or C. rugosus, with C. purpureus being the dominant species. Early juveniles grew until October. The abundance of early juveniles decreased with decreasing air temperatures, and dead individuals were found during the overwintering period. The low-temperature tolerance ability of C. purpureus was stronger than that of C. rugosus. Some crabs successfully overwintered, and all were identified as C. purpureus. The growth and overwintering success of juveniles varied among the survey sites depending on the local temperature regime. Our results highlight the frontier for expanding the northern geographical distribution of land hermit crab populations by the colonization and overwintering success of C. purpureus.

Key words: Terrestrial hermit crabs, Biogeography, Larval dispersal, Thermal adaptation, Low-temperature tolerance.

Citation: Sanda S, Hamasaki K, Dan S, Kitada S. 2019. Expansion of the northern geographical distribution of land hermit crab populations: colonization and overwintering success of Coenobita purpureus on the coast of the Boso Peninsula, Japan. Zool Stud 58:25. doi:10.6620/ZS.2019.58-25.

Supplementary Materials: Fig. S1 | Fig. S2 | Fig. S3 | Fig. S4 | Fig. S5A | Fig. S5B | Fig. S5C | Fig. S6 | Fig. S7
                                                 Table S1 | Table S2 | Table S3 | Table S4 | Table S5 | Table S6 | Table S7 | Table S8 | Table S9