Geographic distribution of nonindigenous marine invertebrates on 64 islands in Japanese waters
別タイトル
日本の64の島嶼における外来海産無脊椎動物の地理的分布
著者
岩崎, 敬二
(Iwasaki, Keiji)
奈良大学文学部
版
publisher
出版地
奈良
出版者
奈良大学
上位タイトル
奈良大学紀要
(Memoirs of the Nara University).
No.48
(2020.
2)
,p.1-
18
識別番号
ISSN
03892204
抄録
Surveys of nonindigenous marine invertebrates (NMI) were conducted at 424 sites (218 harbors and 206 rocky, boulder, or embanked shores outside of the harbors) on 64 inhabited islands in Japanese waters from 2014 to 2017. Eleven species of NMI were discovered during the surveys: the calyptraeid slipper snail, Crepidula onyx; three mytilid mussels, Mytilus galloprovincialis, Perna viridis, and Xenostrobus securis; five balanid barnacles, Amphibalauns amphitrite, A. eburneus, A. improvisus, Balanus glandula, and Perforatus perforatus; the portunid crab, Carcinus aestuarii; and the ascidiid ascidian, Asicidiella aspersa. One or more species of NMI were found at 177 sites on 55 islands. In total, one or more species of NMI were present at more than 40% of the study sites and more than 85% of islands surveyed. They occurred exclusively at the harbors (148 out of 206 harbors), while they were rarely found on the shores (29 out of 206 shores). Multiple Poisson regression analysis revealed that the latitude, the index of artificial environment , and the number of indigenous sessile invertebrate species at a site had positive relationships with the unmbere of NMI at a site, and the number of indigenous motile invertebrate species at a site had a negative relationship with the number of NMI. This suggested that high latitude, a higher degree of artificial environment, and higher species abundance of indigenous sessile invertebrates had positive effects on the occurrence of NMI, and the species abundance of indigenous motle invertebrates had a negative effect on NMI.
