Range expansion of non-indigenous marine benthos introduced into Japan through human activities

Keiji Iwasaki, Kyoko Kinoshita, Kenji Okoshi, Taeko Kimura, Takeharu Kosuge, Takao Suzuki, Eijiroh Nishi, Teruaki Nishikawa, Ikuo Hayashi, Yasuhisa Henmi, Toshio Furota, Hiroshi Mukai, Toshiyuki Yamaguchi, Ryohei Yamanishi

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


The pattern of spread and range expansion of eight species of non-indigenous marine animals introduced into Japan was investigated, using the data obtained from questionnaire surveys. The surveys, asking respondents to send information on the occurrence in the field or published/unpublished records for introduced and cryptogenic species, was conducted by the Committee for the Preservation of the Natural Environment, the Japanese Association of Benthology, in 2002-2003. Over 50 records on occurrence were obtained for each of the eight benthic animals, Crepidula onyx (Gastropoda), Mytilus galloprovincialis (Bivalvia), Xenostrobus securis (Bivalvia), Hydroides elegans (Polychaeta), Balanus amphitrite (Cirripedia), Balanus eburneus (Cirripedia), Balanus improvisus (Cirripedia) and Carcinus aestuarii (Decapoda). All of them were presumed to be introduced via shipping. The spreading distances of the recorded sites from the site of the first record in Japan were potted as a function of time after the year of the first record and were analysed through correlation and regression analyses. Due to rapid expansion soon after the first record or lack of information on the geographic distribution, none of the eight species showed an initial establishment phase during which no range expansion takes place in the initial stage of the invasion. For the five species, C. onyx, M. galloprovincialis, X. securis, B. improvisus, and C. aestuarii, a significant, positive correlation was detected between the farthest distance of the recorded sites from the site of first record in each year and time after the year of first record. Regression of the farthest distance against time revealed that the average speed of spread was 26.4 km year-1 for C. onyx, 10.9 km year-1 for M. galloprovincialis, 23.9 km year-1 for X securis, 13.9 km year-1 for B. improvisus, and 24.7 km year-1 for C. aestuarii. The distance-versus-time curves for the five species showed no saturation phase during which no range expansion takes place in the final stage of invasion. Thus their geographic ranges were considered expanding even recently, from the Pacific coasts to the Japan Sea coasts or northward, without reaching a geographic limit to available space. Range expansion for the two barnacles, B. amphitrite and B. eburneus, was considered to have occurred only in the early stage of invasion and ceased by 10-15 years after the date of first record. Information on the geographic distribution of the remaining one species, H. elegans, was not enough to examine the pattern of its range expansion.

Original languageEnglish
Pages (from-to)132-144
Number of pages13
JournalBulletin of the Plankton Society of Japan
Issue number2
Publication statusPublished - 2004 Aug 1


  • Introduction via shipping
  • Non-indigenous marine animals
  • Questionnaire survey
  • Range expansion
  • Speed of spread

ASJC Scopus subject areas

  • Oceanography
  • Aquatic Science


Dive into the research topics of 'Range expansion of non-indigenous marine benthos introduced into Japan through human activities'. Together they form a unique fingerprint.

Cite this