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㇏⏣㸦ᑠ㇂㔝㸧 ᭷ຍ 1*ࠊᗈ℩ 㞞ே 2ࠊ୰㔝 ᬛஅ 3ࠊᑠᯇ ᾈ඾ 4ࠊᑎ⏣ ❳ኴ 5㇏⚟ 㧗ᚿ 6, 7 㛗஭ ⿱ᏘᏊ 4, 6 ࠊ௒஭ ோ 1ࠊᑠᒣ⏣ భ㍜ 1ࠊྥ ဴႹ 8ࠊᕝཱྀ ኱ᮁ 8     㧗ᕊ ᫓ኵ 9ࠊ㝯୍ 1ࠊ᳃ ⱥ❶ 1ࠊ୕Ꮿ ⿱ᚿ 2Preliminary report of marine macrofauna of Nishinoshima Island

Yuka TOYOYA (KOYANO) 1*, Masato HIROSE2, Tomoyuki NAKANO3,

Hironori KOMATSU4, Ryuta TERADA5, Takashi TOYOFUKU6, 7, Yukiko NAGAI4, 6,

Hitoshi IMAI1, Yusuke OYAMADA1, Akitsugu MUKAI8, Dairo KAWAGUCHI8,

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Haruo TAKAMINE9㸪Ryuichi MINATO1, Hideaki MORI1 & Hiroshi MIYAKE2

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1. ୍⯡㈈ᅋἲே⮬↛⎔ቃ◊✲ࢭࣥࢱ࣮㸦ࠛ130-8606 ᮾி㒔ቚ⏣༊Ụᮾᶫ 3-3-7㸧
Japan Wildlife Research Center, 3-3-7 Kotobashi, Sumida, Tokyo 130-8606, Japan.
2㸬໭㔛኱Ꮫᾏὒ⏕࿨⛉Ꮫ㒊㸦ࠛ252-0373 ⚄ዉᕝ┴┦ᶍཎᕷ༡༊໭㔛 1-15-1㸧
School of Marine Biosciences, Kitasato University, 1-15-1 Kitasato, Minami, Sagamihara,

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Kanagawa 252-0373, Japan.
3. ி㒔኱Ꮫࣇ࢕࣮ࣝࢻ⛉Ꮫᩍ⫱◊✲ࢭࣥࢱ࣮℩ᡞ⮫ᾏᐇ㦂ᡤ㸦ࠛ649-2211 ࿴ḷᒣ┴す∹፝㒆ⓑ὾⏫ 459㸧

Seto Marine Biological Laboratory, Field Science and Education Center, Kyoto University, 459

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Shirahama, Nishimuro, Wakayama 649-2211, Japan.
4. ᅜ❧⛉Ꮫ༤≀㤋㸦ࠛ305-0005 Ⲉᇛ┴ࡘࡃࡤᕷኳஂಖ 1-12-30㸧
Natural Museum of Nature and Science, 1-12-30 Amakubo, Tsukuba, Ibaraki 305-0005, Japan.
5. 㮵ඣᓥ኱Ꮫ኱Ꮫ㝔㐃ྜ㎰Ꮫ◊✲⛉㸦ࠛ890-0065 㮵ඣᓥ┴㮵ඣᓥᕷ㒆ඖ 1- 21-24㸧
United Graduate School of Agricultural Sciences, Kagoshima University, 1-21-24 Koorimoto,

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Kagoshima, Kagoshima 890-0065, Japan.
6. ᅜ❧◊✲㛤Ⓨἲேᾏὒ◊✲㛤Ⓨᶵᵓ ㉸ඛ㗦◊✲㛤Ⓨ㒊㛛 (X-star)㸦ࠛ237-0061 ⚄ዉᕝ┴ᶓ㡲㈡ᕷኟᓥ⏫ 2-15㸧

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X-Star, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15Natsushima-cho, Yokosuka, Kanagawa 237-0061, Japan.

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7. ᮾிᾏὒ኱Ꮫᾏὒ㈨※⎔ቃᏛ㒊㸦ࠛ108-8477 ᮾி㒔 ༊ ༡ 4 ୎┠ 5−7㸧Tokyo University of Marine Science and Technology (TUMSAT) , 4-5-7 Konan, Minato, Tokyo

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108-8477, Japan.
8. ୍⯡♫ᅋἲே ࢔࢖ࣛࣥࢬࢣ࢔㸦ࠛ100-2211 ᮾி㒔ᑠ➟ཎᮧẕᓥᏐ㟼ἑ㸧
Islands Care, Shizusawa, Hahajima, Ogasawara, Tokyo 100-2211, Japan.
9. HARUKA-MARU㸦ࠛ100-2101 ᮾி㒔ᑠ➟ཎᮧ∗ᓥᏐΎ℩㸧
HARUKA-MARU, Kiyose, Chichijima, Ogasawara, Tokyo 100-2101, Japan.

*ytoyota@jwrc.or.jp (author for correspondence)

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2021 ᖺ 7 ᭶࡟すஅᓥ࿘ᅖࡢᾏὒ⎔ቃ࠾ࡼࡧᾏὒ⏕≀┦ㄪᰝࢆ⾜ࡗࡓࠋすஅᓥࡢすഃࡢᾏ
ᇦ࡛ࡣᄇⅆࡢᙳ㡪࡜ᛮࢃࢀࡿኚⰍᇦࡀ☜ㄆࡉࢀࠊ໭ഃࡢᾏᗏࡣⅆᒣ⅊࡛そࢃࢀ࡚࠾ࡾࠊ3m
௨ୖࡢ⁐ᒾᵝࡢᒾࡸᄇ▼࡜ᛮࢃࢀࡿᑤࡗࡓᒾ▼ࡀⅬᅾࡋ࡚࠸ࡓࠋᮏㄪᰝ࡛ࡣࠊ14 㛛 253✀௨ୖࡀ୺࡟すஅᓥ໭ഃࡢᾏᓊ࠾ࡼࡧᾏᇦࡼࡾ☜ㄆࡉࢀࡓࠋᗏ⏕⏕≀ࡢከᵝᛶࡣపࡃࠊ኱
ᆺࡢᾏ⸴㢮ࡸࢧࣥࢦ㢮ࡣ☜ㄆࡉࢀ࡞࠿ࡗࡓࠋᾏᗏࡢᒾ▼ୖ࡟≉࡟௜╔ᩘࡀከ࠿ࡗࡓࡶࡢࡣ
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ࡿศ㢮⩌࡛࠶ࡿࡇ࡜࠿ࡽࠊ௒ᅇほᐹࡋࡓすஅᓥ࿘㎶ࡢᾏᗏ⎔ቃࡣࠊ⩌㞟ࡢ෌⏕ึᮇࡢ≧ែ࡛࠶ࡿ࡜⪃࠼ࡽࢀࡿࠋࡲࡓࠊࣉࣛࣥࢡࢺࣥࡢ⏕≀㔞ࡀ㠀ᖖ࡟ᑡ࡞ࡃࠊ㈋ᰤ㣴≧ែ࡛࠶ࡾࠊ
ᗏ⏕⏕≀ࡢᗂ⏕ࡣࣉࣛࣥࢡࢺࣥ඲యࡢ 1.5㸣࡟ࡍࡂ࡞࠿ࡗࡓࠋ௨ୖ࠿ࡽࠊすஅᓥ࡬ࡢᗏ⏕⏕≀ࡢຍධ࡜ᐃ╔࡟ࡘ࠸࡚ࡣ᫬㛫ࡀ࠿࠿ࡿ࡜ᛮࢃࢀࡿࠋࡋ࠿ࡋࡑࡢ୍᪉࡛ࠊ2020 ᖺ 7 ᭶ࡢ኱つᶍᄇⅆᚋ࡟࠾࠸࡚ࡶࠊすஅᓥ࿘㎶ࡢỈ῝ࡢ῝࠸ሙᡤ࡟ࡣࠊඖࡢ⏕≀⩌㞟ࡀṧࡗ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡾࠊࡑࡇ࠿ࡽࡢᗂ⏕ຍධࡀ࠶ࢀࡤࠊࡼࡾ᪩ࡃ⏕≀ࡢ㑄⛣ࡀࡍࡍࡴ࡜ᛮࢃࢀࡿࠋ
ᮏㄪᰝ࡛ࡣࠊᾏὒᓥ࡟࠾ࡅࡿ⏕ែ⣔ࡢ୍ḟ㑄⛣ࡢึᮇẁ㝵ࢆグ㘓࡛ࡁࡓࠋ௒ᚋࡣࠊすஅᓥ࿘㎶ࡢ῝ᾏᇦ࠾ࡼࡧࠊ࿘㎶ࡢᾏὶࡢ≧ἣࡸྛ⏕≀✀ࡢ⦾Ṫࢩ࣮ࢬࣥ࡞࡝ࡶ⪃៖࡟ධࢀࠊᾏ

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1㸬ࡣࡌࡵ࡟ すஅᓥ࡛ࡣࠊ㏆ᖺάⓎ࡞ⅆᒣάືࡀぢࡽࢀ࡚࠾ࡾࠊ1973 ᖺ࡟すஅᓥ㏆ഐ࡛ᾏᗏⅆᒣࡀᄇⅆࡋ࡚௨㝆ࠊᓥࡢ㠃✚ࢆ኱ᖜ࡟ᣑ኱ࡋ࡚ࡁࡓࠋ2013 ᖺ࡟ࡣࠊ40 ᖺࡪࡾ࡟すஅᓥ༡ᮾἈ࡛
ᾏᗏⅆᒣࡀᄇⅆࡋࠊ⁐ᒾ࡟ࡼࡾᪧすஅᓥࡢ 95㸣௨ୖࡀᒾ▼ࡢୗ࡟ᇙࡲࡗࡓࠋࡑࡢᚋࠊ2017ᖺ࠾ࡼࡧ 2018 ᖺ࡟ᄇⅆࡀ⏕ࡌࠊ㠃✚ࡣ 2.95km2 ࡟㐩ࡋࡓࠋࡉࡽ࡟ 2020 ᖺ 7 ᭶ࡢ኱つᶍ࡞ᄇⅆ࡟ࡼࡗ࡚ࠊᪧすஅᓥࡣ⁐ᒾ࡟ࡼࡾࡍ࡭࡚ᇙࡲࡾࠊࡑࡢᚋࡶ 2021 ᖺ 9 ᭶࡟ᑠつᶍ࡞ᄇⅆࡀ㉳ࡇࡿ࡞࡝ࠊάⓎ࡞ⅆᒣάືࡀ⥆࠸࡚࠸ࡿࠋ1973 ᖺࡢᄇⅆ࠿ࡽࡇࢀࡲ࡛࡟ࠊ⏕≀ࡸᆅ

− 114 −

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ᙧࠊᆅ㉁࡟㛵ࡍࡿୖ㝣ㄪᰝࡣ 2019 ᖺࡢࡶࡢࢆྵࡵࠊᑡ࡞ࡃ࡜ࡶ 14 ᅇ⾜ࢃࢀࡓ㸦᳃࡯࠿ࠊ2020㸧
ࠋ୍᪉ࠊすஅᓥ࿘ᅖࡢᾏᇦࡢ⏕≀┦ࡢㄪᰝࡣࠊᪧᓥ࡜᪂ᓥࡀ⤖ྜࡍࡿ๓ࡢ 1974 ᖺ 3᭶࡟㨶㢮࡜ື≀ࣉࣛࣥࢡࢺࣥࢆྵࡴㄪᰝ࡜ࠊ⤖ྜᚋࡢ 1975 ᖺ 6 ᭶࡟ࢽࢩࣀࢩ࣐࣍࢘࢟࢞
ࢽ࡞࡝࢝ࢽ㢮ࢆྵࡴἢᓊᇦࡢᗏ⏕⏕≀ࡢㄪᰝࡀࠊࡑࢀࡒࢀ⾜ࢃࢀࡓࡢࡳ࡛࠶ࡿ㸦Takeda &Kurata, 1977㸧
ࠋࡲࡓࠊ2019 ᖺࡢୖ㝣ㄪᰝ᫬࡟ࡶᾏᇦࡢ⏕≀┦ࡢㄪᰝࡣ₻㛫ᖏࢆ㝖ࡁ⾜ࢃࢀࡎࠊ㏆ᖺࡢᾏᇦࡢ⏕≀┦࡟ࡘ࠸࡚ࡢ▱ぢࡣஈࡋ࠸ࠋ

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すஅᓥࡢࡼ࠺࡟ᄇⅆ࡟ࡼࡗ࡚᪂ࡓ࡞㝣ᆅࡀᙧᡂࡉࢀࡓ౛࡜ࡋ࡚ࠊ࢖ࣥࢻࢿࢩ࢔ࡢࢡࣛ࢝
ࢱ࢘ᓥࡸ࢔࢖ࢫࣛࣥࢻࡢࢫࣝࢶ࢙࢖ᓥࡀ▱ࡽࢀࡿࡀࠊ࠸ࡎࢀࡶ኱㝣ᓥ࡛࠶ࡿ࡜࡜ࡶ࡟ࠊ㏆㞄ࡢ᭷ேᓥ࠿ࡽ㏆㊥㞳࡟࠶ࡿࡓࡵࠊᓥ࿘ᅖࡢᾏὒ⏕ែ⣔ࡣࡑࡢᙳ㡪ࢆẚ㍑ⓗ▷ᮇ㛫࡛ཷࡅࠊᅇ᚟ࡋࡓ࡜⪃࠼ࡽࢀࡿ㸦Sigurdsson, 2000; Barber et al., 2002; Gunnarson & Hauksson, 2009;
Starger et al., 2010㸧ࠋ୍᪉ࠊすஅᓥࡣࠊ᭱ࡶ㏆࠸᭷ேᓥࡢ∗ᓥ࠿ࡽ⣙ 130km 㞳ࢀ࡚࠸ࡿᏙ❧ࡋࡓ↓ேࡢᾏὒᓥ࡛࠶ࡿࠋ୍᪦ᓥࡢⅆཱྀ࠿ࡽ኱㔞ࡢ⁐ᒾࡢᄇฟࡀ㉳ࡇࢀࡤࠊἢᓊࡢ⏕≀┦ࡣࡍ࡭࡚ࠊ⁐ᒾ࡟↝ࡁᑾࡃࡉࢀࠊ⁐ᒾ࡟そࢃࢀࠊࡉࡽ࡟኱㔞ࡢⅆᒣ⅊࡟ࡶᇙࡶࢀ࡚ࡋࡲ࠸ࠊ
ᓥ࿘ᅖࡢᾏὒ⏕ែ⣔ࡣࠊ୍ḟ㑄⛣ࡢึᮇ࡟ࣜࢭࢵࢺࡉࢀࡿࠋᓥ࿘ᅖࡢᾏὒ⏕ែ⣔ࡢᅇ᚟࡟ࡣ୍ᐃࡢᮇ㛫ࡀ࠿࠿ࡾࠊ࠿ࡘࡑࡢᅇ᚟ࡢ㐣⛬࡟ࡣேⅭⓗ࡞ᙳ㡪ࡀᑡ࡞࠸࡜⪃࠼ࡽࢀࡿࡓࡵࠊすஅᓥࡣࡇࡢᆅ⌫ୖ࡛⌧ᅾࠊ၏୍ᾏὒᓥ࡟࠾ࡅࡿ⏕ែ⣔ࡢ୍ḟ㑄⛣ࢆほᐹ࡛ࡁࡿሙᡤ࡛࠶ࡿࠋすஅᓥࡢࡼ࠺࡟Ꮩ❧ࡋࡓᾏὒᓥࡢᄇⅆᚋࡢᓥ࿘ᅖࡢᾏὒ⏕ែ⣔࡟ࡘ࠸࡚グ㘓ࡋࡓ౛ࡣᑡ࡞ࡃࠊ2020 ᖺࡢ኱つᶍ࡞ᄇⅆᚋࡢ⌧ᅾࡣࠊᄇⅆ࡟ࡼࡗ࡚኱ࡁࡃ࠿ࡃ஘ࡉࢀࡓ⏕ែ⣔ࡀᅇ᚟ࡍࡿ㐣⛬ࢆグ㘓ࡍࡿୡ⏺࡛ࡶ㢮ࢆぢ࡞࠸㈗㔜࡞ᶵ఍࡜࠸࠼ࡿࠋࡑࡇ࡛ᮏㄪᰝ࡛ࡣࠊすஅᓥ࿘ᅖࡢᾏᇦࡢ⎔ቃ࡜⏕≀┦ࡢ㑄⛣ࡢึᮇ≧ែࢆグ㘓ࡍࡿࡇ࡜ࢆ┠ⓗ࡜ࡋࡓࠋᮏ◊✲ࡣࠊ᪂ࡓ࡟ㄌ⏕ࡋࡓᾏὒᓥࡢᾏὒ⏕ែ⣔ࡢᡂࡾ❧ࡕࡢゎ᫂࡟ࡶ㈉⊩ࡍࡿࡶࡢ࡜⪃࠼ࡽࢀࡿࠋ

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㆙ᡄ⠊ᅖእࡢすஅᓥࡢ୺࡟໭ഃࡢᾏᇦ࡛⾜ࡗࡓ㸦ᅗ 1㸧ࠋ୍㒊ࡢỈ㉁ㄪᰝ࠾ࡼࡧࣉࣛࣥࢡࢺ
ࣥㄪᰝ࡟㛵ࡋ࡚ࡣࠊすஅᓥࡢ໭ഃࡢᾏᇦ௨እ࡟ࡘ࠸࡚ࡶ⾜ࡗࡓ㸦ᅗ 1㸧ࠋࢧࣥࣉࣜࣥࢢࡣ୺
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 すஅᓥ࿘ᅖࡢᾏᗏᆅᙧࡢኚ໬ࢆᢕᥱࡍࡿࡓࡵࠊ2017 ᖺ࡟ᾏୖಖᏳᗇࡀⓎ⾜ࡋࡓ᪥ᮏ༡᪉
ㅖᓥ➨ 6556 ྕ 8㸦ᾏୖಖᏳᗇࠊ2017㸧࡜⯪⯧㐠⯟ࡢᏳ඲ୖࠊཧ⪃ࡢࡓࡵ࡟➨୕㛤ὒ୸ࡼࡾྲྀᚓࡉࢀࡓᾏᗏᆅᙧᅗ㸦᳃࡯࠿ࠊ2023㸧ࢆẚ㍑ࡋࡓࠋࡲࡓࠊᾏὒ⎔ቃࢆᢕᥱࡍࡿࡓࡵࠊ7᭶ 9㹼12 ᪥࡟ St.1㹼5ࠊ7ࠊ8 ࡛ࡣ࣓࣮ࣔࣜCTD㸦RINKO Profiler, JFE ࢔ࢻࣂࣥࢸࢵࢡᰴᘧ఍
♫㸧ࢆ⏝࠸࡚ࠊSt.S1㹼S4 ࡛ࡣ࣓࣮ࣔࣜCTD ࡲࡓࡣ CTD㸦ACTD-CMP, JFE ࢔ࢻࣂࣥࢸࢵ
ࢡᰴᘧ఍♫㸧ࢆ⏝࠸࡚ࠊࡑࢀࡒࢀỈ㉁ㄪᰝࢆ⾜ࡗࡓࠋࡲࡓࠊ13 ᪥࡟ࡣ࣓࣮ࣔࣜCTD ࠾ࡼࡧࣉࣛࣥࢡࢺࣥࢿࢵࢺ࡟๓㏙ࡢ CTD ࢆྲྀࡾ௜ࡅ࡚すஅᓥ࿘ᅖ 8 ᪉఩ࡢỈ㉁ࡢㄪᰝࢆ⾜ࡗࡓࠋࣉࣛࣥࢡࢺࣥࢿࢵࢺ࡟ྲྀࡾ௜ࡅࡓ CTD ࡢグ㘓ࡣࠊ࣓࣮ࣔࣜCTD ࡢ⤖ᯝ࡜㔜」ࡍࡿࡓ
ࡵᮏሗ࿌࡛ࡣ┬␎ࡍࡿࠋ࣓࣮ࣔࣜCTD ࡛ࡣྛࠎࡢỈ῝࡟࠾ࡅࡿỈ ࠊሷศࠊࢡࣟࣟࣇ࢕ࣝ aࠊ⃮ᗘࠊDO ࢆグ㘓ࡋࠊCTD ࡛ࡣࠊྛࠎࡢỈ῝࡟࠾ࡅࡿỈ ࠊሷศࢆグ㘓ࡋࡓࠋࡲࡓࠊ
7 ᭶ 9 ᪥࡟ࡣ St.1ࠊ2ࠊ4 ࡛㏱᫂ᗘᯈࢆ⏝࠸࡚ᾏỈࡢ㏱᫂ᗘࢆ ᐃࡋࡓࠋ
2-2㸬₻㛫ᖏ⏕≀ すஅᓥࡢ₻㛫ᖏࡢ⏕≀┦ࢆᢕᥱࡍࡿࡓࡵࠊ7 ᭶ 7 ᪥࡟ୖ㝣ᆅࡢ᥈⣴ࢆ⾜ࡗࡓ㝿࡟₻㛫ᖏࡢほᐹࢆ⾜࠸ࠊ┠ど࡛☜ㄆࡉࢀࡓ⏕≀ࢆ᥇ྲྀࡋࡓࠋ
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2-3㸬ᗏ⏕⏕≀ すஅᓥࡢᗏ⏕⏕≀┦ࢆᢕᥱࡍࡿࡓࡵࠊ7 ᭶ 9 ᪥࡟ St.E1ࠊE2ࠊE4 ࡛ 15 cm ᅄ᪉ࡢᑠᆺ࢚
ࢡ࣐ࣥࣂ࣮ࢪ᥇Ἶჾ㸦㞳ྜ♫㸧ࢆ⏝࠸࡚ᗏ⏕⏕≀࡜ᗏ㉁ࡢ᥇㞟ࢆ⾜ࡗࡓࠋࡲࡓࠊ7 ᭶ 10㹼
12 ᪥࡟ St.S1㹼S4 ࡛₯Ỉ࡟ࡼࡿᗏ⏕⏕≀ࡢ᧜ᙳ࠾ࡼࡧࢧࣥࣉࣜࣥࢢࢆ⾜ࡗࡓ㸦ᅗ 2ࠊ3㸧ࠋ
St.S1 ࠾ࡼࡧ St.S4 ࡛ࡣᾏᗏ࡟ 1m×1m ࡢ᪉ᙧᯟࢆタ⨨ࡋࠊࡑࡢᯟෆࡢᗏ㉁ࢆ࣓࡛࢝ࣛ᧜ᙳ
ࡍࡿ࡜࡜ࡶ࡟ࠊᯟෆࡢ 50cm×50cm ࡢᗏ㉁ࢆࢫࢥࢵࣉ࡛ࡍࡃࡗ࡚᥇㞟ࡋࡓࠋ᥇㞟ࡋࡓᗏ⏕⏕≀࡜ᗏ㉁ࡣ⫗║࡟ࡼࡿࢯ࣮ࢸ࢕ࣥࢢࢆ⾜ࡗࡓᚋ㸪70㹼99%࢚ࢱࣀ࣮ࣝࡶࡋࡃࡣ 2㹼10%ᾏỈ࣐࡛࣍ࣝࣜࣥᅛᐃࡋᶆᮏ࡜ࡋࡓࠋࡲࡓࠊ୍㒊ࡢศ㢮⩌࡟ࡘ࠸࡚ࡣᅛᐃࢆ⾜ࢃࡎ෭෾࡛
ಖᏑ࣭㍺㏦ࡋࡓࠋ◊✲ᐊ࡟ᣢࡕᖐࡗࡓᶆᮏࡣᐇయ㢧ᚤ㙾㸦SZX16, Olympus ♫㸧࠾ࡼࡧ௜ᒓࡢ࣓࢝ࣛ㸦DP73㸪Olympus ♫㸧࡛ほᐹ࣭᧜ᙳࡋࠊ⏕≀ࡢྠᐃࢆ⾜ࡗࡓࠋ₯Ỉㄪᰝ࡛ࡣ୺
࡟ࠊ᫨⾜ᛶ⏕≀ࡢほᐹ࡜᥇㞟࡜࡞ࡿࡓࡵࠊኪ⾜ᛶ⏕≀ࡢㄪᰝࢆ┠ⓗ࡜ࡋ࡚ St.A ࡜ St.8 ࡛ࡶࢇ࡝ࡾ㸦࠾㨶࣮࢟ࣛ, TAKAMIYA㸧ࢆࠊSt.A ࡛⥳Ⰽࡢࢣ࣑࢝ࣝࣛ࢖ࢺ࡜㗽ࢆධࢀࡓࣛ࢖
ࢺࢺࣛࢵࣉ㸦ᅗ 4㸧ࢆࠊࡑࢀࡒࢀࡋ࠿ࡅࠊኪ⾜ᛶࡢ⏕≀ࡢᤕ⋓ࢆヨࡳࡓࠋࡶࢇ࡝ࡾ࡟ࡣࣖ
࣐࣋㸦ࣁ࢚㸧㔮ࡾ⏝ᐤࡏ࢚ࢧ㸦ᐤࡏኴ㑻, ࣐࣮ࣝ࢟ࣘᰴᘧ఍♫㸧࠾ࡼࡧ࣐ࢧࣂࢆ㣵࡜ࡋ࡚ධࢀࡓࠋ
2-4㸬᭷Ꮝ⹸ ₯Ỉㄪᰝ᫬࡟St.S1㹼S4 ࡢᾏᗏ࡛50ml ࢩࣜࣥࢪࡲࡓࡣ300ml ࡢࢧࣥࣉࣝ⎼ࢆᕪࡋ㎸ࢇ࡛ሁ✚≀ࢆ᥇ྲྀࡋࡓࠋSt.S1 ࡛ࡣ 2 ࠿ᡤࠊSt.S2㹼S4 ࡛ࡣࡑࢀࡒࢀ 1 ࠿ᡤ࡛᥇ྲྀࢆ⾜ࡗࡓࠋ1࠿ᡤ࡟ࡘࡁ 3 ᮏࡢࢧࣥࣉࣝࢆ᥇ྲྀࡋࠊィ 15 ᮏࡢࢧࣥࣉࣝࢆᚓࡓࠋ᥇ྲྀࡋࡓሁ✚≀ࡣࡑࡢ− 116 −

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᪥ࡢ࠺ࡕ࡟࣮ࣟࢬ࣋ࣥ࢞ࣝᾏỈ࢔ࣝࢥ࣮࡛ࣝᅛᐃࡋࠊᐇ㦂ᐊ࡟ᣢࡕᖐࡗࡓࠋྛࢧࣥࣉࣝࡢ
ሁ✚≀ࢆ 500μm ࡜ 32μm ࡢ⠠࡟࠿ࡅྛศ⏬ࡈ࡜࡟஝⇱ࡉࡏࠊࡑࡇ࠿ࡽᐇయ㢧ᚤ㙾㸦SteREO
Discovery. V12, Zeiss ♫㸧ࢆ౑⏝ࡋࠊࣁࣥࢻࣆࢵࢡ࡛ᣠ࠸ฟࡋࡓࠋᢳฟࡉࢀࡓ᭷Ꮝ⹸ࡣᐇయ
㢧ᚤ㙾࡛ほᐹࡋࡓࠋ
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2-5㸬࣓࢖࢜࣋ࣥࢺࢫ㸦᭷Ꮝ⹸௨እ㸧 ࣓࢖࢜࣋ࣥࢺࢫ㸦meiobenthos㸧ࡣ୍⯡ⓗ࡟ 1mm ࡢ⠠ࢆࡍࡾᢤࡅࠊ32- 36μm ࡢ⠠࡟␃ࡲࡿᑠᆺࡢᗏ⏕⏕≀ࢆᣦࡍ㸦ᒣᓮ࡯࠿ࠊ2019㸧
ࠋSt.E1 ࠾ࡼࡧ St.E2 ࡛᥇Ἶࡋࡓᗏ㉁ࠊ࠾ࡼࡧ
ྛ₯ỈㄪᰝᆅⅬ࡛᥇ྲྀࡋࡓᗏ㉁ࡣ⯪ୖ࡛ࡣ෭෾ࡶࡋࡃࡣ࣐࣍ࣝࣜࣥᅛᐃ࡛ಖᏑ࣭㍺㏦ࡋࠊ
◊✲ᐊ࡟ᣢࡕᖐࡗࡓᚋ࡟Ὑ࠸ฟࡋἲ㸦ᒣᓮ࡯࠿ࠊ2019㸧࡟ࡼࡗ࡚࣓࢖࢜࣋ࣥࢺࢫࢆ༢㞳ࡋࡓࠋᢳฟࡉࢀࡓ࣓࢖࢜࣋ࣥࢺࢫࡣᐇయ㢧ᚤ㙾㸦SZX16, Olympus ♫㸧࠾ࡼࡧಽ❧㢧ᚤ㙾
㸦CKX41, Olympus ♫㸧࡛ほᐹࡋࠊᐇయ㢧ᚤ㙾௜ᒓࡢ࣓࢝ࣛ㸦DP73㸪Olympus ♫㸧࠾ࡼࡧಽ❧㢧ᚤ㙾࡟ྲྀࡾ௜ࡅࡓࢹࢪࢱ࣓ࣝ࢝ࣛ㸦EOS Kiss X5㸪Canon㸧࡛᧜ᙳࡋࡓᚋࠊྍ⬟࡞⠊ᅖ࡛ྠᐃࡋࡓࠋ
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2-6㸬㨶㢮 すஅᓥ࿘㎶ᾏᇦࡢ㨶㢮┦ࢆᢕᥱࡍࡿࡓࡵࠊ₯Ỉㄪᰝ୰࡟᧜ᙳࡋࡓ෗┿࠾ࡼࡧᫎീࢆࡶ࡜
࡟ྠᐃࢆ⾜ࡗࡓࠋᮏㄪᰝࡣ୺࡟すஅᓥ࿘㎶ᾏᇦࡢᗏ⏕⏕≀࠾ࡼࡧࣉࣛࣥࢡࢺࣥࡢ⏕≀┦ㄪᰝࢆ┠ⓗ࡜ࡋ࡚࠸ࡓࡓࡵࠊ㨶㢮ࢆ┠ⓗ࡜ࡋࡓ᧜ᙳࡣ࡯࡜ࢇ࡝⾜ࢃ࡞࠿ࡗࡓࠋ
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2-7㸬ࣉࣛࣥࢡࢺࣥ すஅᓥ࿘㎶ᾏᇦࡢࣉࣛࣥࢡࢺࣥ┦ࢆᢕᥱࡍࡿࡓࡵࠊ7 ᭶ 9㹼11 ᪥ࡢ᫨㛫࡟ St.3ࠊ5ࠊ7ࠊ8
࡟࡚ྛ 2 ᅇࡎࡘィ 8 ᅇ໭ཎᘧ⾲ᒙࣉࣛࣥࢡࢺࣥࢿࢵࢺ㸦ཱྀᚄ 30cm, ⥙┠ 0.1mm㸧ࢆ㖄┤ᘬࡁࡋࡓࠋࡲࡓࠊ7 ᭶ 10㹼12 ᪥ࡢ᪥ἐ᫬࠾ࡼࡧ᪥ἐ 1 ᫬㛫ᚋ࡟ྛ 2 ᅇࡎࡘ St. P㸦ᮾഃࠊすഃࠊ༡ഃ㸧࡟࡚ィ 12 ᅇ CTD ࢆࡘࡅࡓ໭ཎᘧ⾲ᒙࣉࣛࣥࢡࢺࣥࢿࢵࢺ㸦ཱྀᚄ 30cm, ⥙┠0.1mm㸧ࢆ 20m ฟࡋ࡚ഴᩳᘬࡁࡋࡓࠋ7 ᭶ 13 ᪥ࡢ༗๓୰࡟ࠊすஅᓥࡢඵ᪉఩ࠊᾏᓊ⥺࠿ࡽ⣙ 1 km ࡢ 8 ᆅⅬ࡛ࠊCTD ࢆࡘࡅࡓ໭ཎᘧ⾲ᒙࣉࣛࣥࢡࢺࣥࢿࢵࢺ㸦ཱྀᚄ 30cm, ⥙┠0.1mm㸧ࢆ 20m ฟࡋ࡚ഴᩳᘬࡁࡋࡓࠋ᥇㞟ࡉࢀࡓࣉࣛࣥࢡࢺࣥࡣࢧࣥࣉࣝ⎼㸦࢔࢖࣮࣎࢖
250ml, ࢔ࢬ࣡ࣥ㸧࡟ධࢀࠊ⤊⃰ᗘ 3㸣࡟࡞ࡿࡼ࠺ᾏỈ࣐࡛࣍ࣝࣜࣥᅛᐃࡋࠊ◊✲ᐊ࡟ᣢࡕᖐࡗࡓࠋࣉࣛࣥࢡࢺࣥࢆᐇయ㢧ᚤ㙾㸦SZM10, Olympus㸧࡛ほᐹࡋࠊ࡛ࡁࡿ㝈ࡾୗ఩ࡢศ
㢮⩌ࡲ࡛✀ࢆྠᐃࡋࡓࠋ
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2-8㸬⁻ὶ≀すஅᓥ࿘㎶ᾏᇦ࡟࠾࠸࡚ࠊ7 ᭶ 9ࠊ11ࠊ12 ᪥࡟┠ど࡛⏥ᯈୖࡼࡾ☜ㄆࡉࢀࡓ⁻ὶ≀ࢆࡓࡶ⥙࡛ᥒ࠸࠶ࡆࠊ⁻ὶ≀࡟௜╔ࡍࡿ⏕≀࠾ࡼࡧ⁻ὶ≀ࢆ㞃ࢀᐙ࡜ࡋ࡚฼⏝ࡋ࡚࠸ࡓ⏕≀ࢆ᥇㞟ࡋࡓࠋᚓࡽࢀࡓ⏕≀ࡣ 70㹼99%࢚ࢱࣀ࣮ࣝࡶࡋࡃࡣ 2㹼10%ᾏỈ࣐࡛࣍ࣝࣜࣥᅛᐃࡋ

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ᶆᮏ࡜ࡋࡓࠋࡲࡓࠊ୍㒊ࡢศ㢮⩌࡟ࡘ࠸࡚ࡣᅛᐃࢆ⾜ࢃࡎ෭෾࡛ಖᏑ࣭㍺㏦ࡋࡓࠋ◊✲ᐊ࡟ᣢࡕᖐࡗࡓᶆᮏࡣᐇయ㢧ᚤ㙾㸦SZX16, Olympus ♫㸧࠾ࡼࡧ௜ᒓࡢ࣓࢝ࣛ㸦DP73㸪Olympus♫㸧࡛ほᐹ࣭᧜ᙳࡋࠊ⏕≀ࡢྠᐃࢆ⾜ࡗࡓࠋ2-9㸬⎔ቃ DNA すஅᓥࡀཎグ㍕ᆅ࡛࠶ࡿࢽࢩࣀࢩ࣐࣍࢘࢟࢞ࢽࢆࡣࡌࡵ࡜ࡍࡿすஅᓥ࿘㎶ᾏᇦ࡟⏕ᜥࡀண᝿ࡉࢀࡿ⇕Ỉᄇฟᇦ࡟⏕ᜥࡍࡿ⏕≀ࢆ☜ㄆࡍࡿࡓࡵࠊ7 ᭶ 9㹼11ࠊ13 ᪥࡟ St.2ࠊ3ࠊ6ࠊ
7ࠊ8ࠊ໭す㸦ኚⰍᇦ㸧࡟࠾࠸࡚ 1 ᆅⅬ࡟ࡘࡁ 4㹼6L ࡢᾏỈࢆࣂࣥࢻ࣮ࣥ᥇Ỉჾ㸦5026-A, 㞳ྜ♫㸧࡛᥇Ỉࡋࡓࠋ᥇ỈࡋࡓᾏỈࡣ⤊⃰ᗘ 0.01㸣ࡢሷ໬࣋ࣥࢨࣝࢥࢽ࣒࡛࢘ᅛᐃࡋࡓ≧ែ࡛⯪ෆࡢ◊✲ᐊ࡟ᣢࡕᖐࡾࠊࡑࡢ᪥ࡢ࠺ࡕ࡟ 0.22 μm ࡢ࣓ࣥࣈࣞࣥࣇ࢕ࣝࢱ࣮㸦࣓ࣝࢡ࣑࣏ࣜ࢔㸧ࢆ౑⏝ࡋ࡚྾ᘬࢁ㐣ࢆ⾜ࡗࡓࠋ1 ᪥ࡢ᥇Ỉ࣭ࢁ㐣ᕤ⛬ࡀࡍ࡭࡚⤊஢ࡋࡓᚋ࡟⵨␃
Ỉࢆࢥࣥࢺ࣮ࣟࣝ࡜ࡋ࡚ࠊ0.22 μm ࡢࢫࢸࣜ࣋ࢡࢫࣇ࢕ࣝࢱ࣮㸦࣓ࣝࢡ࣑࣏ࣜ࢔㸧࡛ࢁ㐣ࡋࡓࠋࣇ࢕ࣝࢱ࣮ୖ࡟ࢁ㐣ࡋࡓ DNA ࡣࢁ㐣ᚋࡓࡔࡕ࡟-20℃࡛ಖᏑࡋࠊ෭෾᮲௳࡛◊✲ᐊ࡟ᣢࡕᖐࡗࡓࠋࣇ࢕ࣝࢱ࣮࠿ࡽࡢ DNA ࡢᢳฟ࡜⢭〇ࡣ⎔ቃ DNA Ꮫ఍㸦2020㸧ࡢᡭ㡰࡟ᚑࡗ࡚⾜࠸ࠊࣜ࢔ࣝࢱ࢖࣒ PCR ࡣ MyGo Mini S Real Time PCR㸦IT-IS Life Science Ltd.㸧ࢆ⏝࠸ࡓࠋ
3㸬⤖ᯝ࠾ࡼࡧ⪃ᐹ
3-1. すஅᓥ࿘㎶ࡢᾏᗏᆅᙧࡢኚ໬࡜ᾏὒ⎔ቃ ୺࡟ㄪᰝࢆ⾜ࡗࡓすஅᓥࡢ໭㒊ࡢὸᾏᇦ࡛ࡣࠊሙᡤ࡟ࡼࡗ࡚ࡣ 2017 ᖺࡼࡾࡶ 10㹼20m⛬ᗘỈ῝ࡀὸࡃ࡞ࡗ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡿ㸦ᅗ 5㸧ࠋ౛࠼ࡤ St.S1 ࡛ࡣ 10m ⛬ᗘࠊSt.S3ࠊS4
࡛ࡣ 20m ⛬ᗘỈ῝ࡀὸࡃ࡞ࡗ࡚࠸ࡿྍ⬟ᛶࡀ♧၀ࡉࢀࡓࠋ୍᪉ࠊ᥇Ἶ࡜ࣉࣛࣥࢡࢺࣥ᥇
㞟ࢆ⾜ࡗࡓỈ῝ 50m ௨῝ࡢ࣏࢖ࣥࢺࡣỈ῝ࡢኚ໬ࡣᑡ࡞࠸ࡼ࠺࡟ᛮࢃࢀࡿࠋ₯Ỉㄪᰝࢆ⾜ࡗࡓ࣏࢖ࣥࢺࡢᾏᗏ࡟ࡣேࡢ⫼ࡢ㧗ࡉࡢᩘಸࡢ⁐ᒾᵝࡢᒾࡸᄇ▼࡜ᛮࢃࢀࡿᑤࡗࡓᒾ
▼ࡀⅬᅾࡋࠊ◁⢏ࡣ⢒ࡃࠊᑠ▼ࡀΰࡊࡗ࡚࠸ࡓࠋ すஅᓥࡢすഃࡢᾏᇦ࡛ࡣࠊᄇⅆࡢᙳ㡪࡜ᛮࢃࢀࡿኚⰍᇦࡀぢࡽࢀࡓ㸦ᅗ 6㸧ࠋすஅᓥ࿘㎶ᾏᇦࠊ᥇Ἶ࠾ࡼࡧ᥇ỈᆅⅬࠊ₯ỈᆅⅬࡢỈ ࠊሷศࠊDOࠊࢡࣟࣟࣇ࢕ࣝ a ࡢศᕸࡣᅗ 7- 1
㹼7-3ࠊ
8-1㹼8-4ࠊ9-1㹼9-2ࠊ10 ࡢ㏻ࡾ࡛࠶ࡿࠋ
༡す㹼す㹼໭すഃࡣᓥࡢᾏᓊ࠿ࡽ 500㹼1,000m⛬ᗘ࡛Ỉ῝ࡀᛴ⃭࡟῝ࡃ࡞ࡿࡓࡵࠊ῝ᒙ࠿ࡽࡢ‪᪼ὶ࡟ࡼࡾࠊ௚ᆅⅬࡼࡾࡶỈ ࡀపࡃ࡞ࡗ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋㄪᰝ୰ࡣ㞵ࡀ㝆ࡽ࡞࠿ࡗࡓࡇ࡜ࠊࡲࡓすஅᓥ࡟ࡣᕝ࡞࡝ࡢ㝣Ỉࡀ࡞࠸ࡓࡵሷศࡣ඲࿘ᅖ࡛࡯ࡰ୍ᵝ࡛࠶ࡗࡓࠋDO ࡣỈ῝ 30m ࠿ࡽ 100m ࠶ࡿ࠸ࡣ 130m ௨῝࡟⾲ᒙ࡜ẚ㍑ࡋ್࡚ࡀ㧗࠸Ỉሢࡀࡳࡽࢀࡓࠋ㏱᫂ᗘࡣ ᐃࡋࡓ 3 ᆅⅬ࡛ࠊ17.0m㸦╔ᗏ㸧ࠊ
31.8mࠊ39.0m ࡛࠶ࡾ㏱᫂ᗘࡣ㧗࠿ࡗࡓࠋࢡࣟࣟࣇ࢕ࣝ a ࡢ್ࡣ୍ᵝ࡟పࡃࠊ㈋ᰤ㣴ࡢᾏᇦ࡛࠶ࡿࡇ࡜ࡀࢃ࠿ࡗࡓࠋࡲࡓࠊࢡࣟࣟࣇ࢕ࣝ a ࡢ್ࡣ༡ᮾഃ࢝ࣝࢹࣛୖࢆ㝖ࡁࠊ⾲ᒙࡼࡾࡶỈ῝ 60㹼150m ௜㏆࡛㧗ࡃ࡞ࡾࠊ⾲ᒙ࡛ࡣࠊ㏱᫂ᗘࡀ㧗ࡃࠊගྜᡂࡢᙉග㜼ᐖࡀ࠶ࡿࡶ

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− 118 −

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ࡢ࡜⪃࠼ࡽࢀࡿࠋࡲࡓࠊ⃮ᗘࡣ༡㹼༡す㹼すࢆ㝖ࡁ㧗࠸ࡀࠊࡈࡃ⾲ᒙ࡟㝈ࡽࢀ࡚࠸ࡿࡇ࡜
࠿ࡽࠊᾏᗏ࠿ࡽࡢᄇฟ≀࡟ࡼࡿࡶࡢ࡛ࡣ࡞ࡃࠊすஅᓥ࠿ࡽࡢὶฟ≀࡟ࡼࡿࡶࡢ࡜ᛮࢃࢀࡿࠋ

3-2㸬すஅᓥࡢᾏὒ⏕≀┦ ඲ㄪᰝ࡛☜ㄆࡉࢀࡓ⏕≀ࡣ 14 㛛 253 ✀௨ୖ࡛࠶ࡗࡓ㸦⾲ 2㸧ࠋ௨ୗ࡟ྛㄪᰝ࡛☜ㄆࡉࢀࡓ⏕≀࡟ࡘ࠸࡚ヲ⣽ࢆグࡍࠋ࡞࠾ࠊ3-2-1.㹼3-3.ࡢ☜ㄆࡉࢀࡓ✀ࢆࡲ࡜ࡵࡓ⾲࡟ࡣࠊ⾲ 2 ࡟
ᥖ㍕ࡉࢀ࡚࠸࡞࠸ゎᯒ୰ࡢ✀ࡶグࡍࠋ
3-2-1㸬₻㛫ᖏ⏕≀⸴㢮 1 ✀ࠊ㈅㢮 1 ✀ࠊ⏥Ẇ㢮 1 ✀ࡀ☜ㄆࡉࢀࡓ㸦⾲ 3-1~ 3-5ࠊᅗ 11㸧ࠋࡇࢀࡽࡣࠊ2020ᖺ 7 ᭶ࡢᄇⅆ࡛ᪧᓥ඲యࡀ⁐ᒾ➼࡛ᇙࡲࡗࡓ࠶࡜࡟ຍධࡋࡓ࡜⪃࠼ࡽࢀࡿࠋࢩ࣑࢜ࢻࣟ┠ࡢ⸴㢮ࡣࠊ₻㛫ᖏ࠿ࡽ₞῝ᖏࡢ⸴㢮⩌㞟࡛ࡼࡃࡳࡽࢀࡿ✀࡛ࠊ⯪⯲ࡢᗏ࡞࡝᪂ࡋ࠸ᇶ㉁࡟
᪩ࡃ࡟ຍධࡍࡿࡓࡵࠊᄇⅆᚋࡢすஅᓥ࡟ࡶ᪩ᮇ࡟ຍධࡋࡓࡶࡢ࡜ᛮࢃࢀࡿࠋࢥ࢘ࢲ࢝ࢱ࣐
࢟ࣅࠊ࢝ࢡࣞ࢖࣡࢞ࢽࡣࠊ2019 ᖺࡢㄪᰝ࡛ࡶぢࡘ࠿ࡗ࡚࠾ࡾࠊ㑄⛣ࡢึᮇẁ㝵࡛☜ㄆࡉࢀ࡚࠸ࡿ✀࡛࠶ࡿࠋ࡝ࡕࡽࡶᾋ㐟ᗂ⏕ᮇࡀ㛗ࡃࠊ஝⇱࡟㠀ᖖ࡟ᙉ࠸✀࡛࠶ࡾࠊⅆᒣᓥ࡞࡝࡬
ࡢ㐺ᛂຊࡢ㠀ᖖ࡟㧗࠸✀࡛࠶ࡿ࡜ᛮࢃࢀࡿࠋࢶࣈ࢖࣎ࢩࣙ࢘ࢪࣥ࢞ࢽࡣࠊᮏㄪᰝ࡛ࡶᮾி
㒔ࡢሗ࿌㸦ᑠ➟ཎ⮬↛ᩥ໬◊✲ᡤࠊ2017㸧࡛ࡶேᕤ≀࡟஌ࡗ࡚⁻ὶࡍࡿᵝᏊࡀ☜ㄆࡉࢀ࡚࠾ࡾࠊࡲࡓᮏㄪᰝ࡛ࡣ₻㛫ᖏ࡛ࡶ☜ㄆࡉࢀ࡚࠸ࡿࡓࡵࠊすஅᓥ࡬ࡢ⏕≀ࡢຍධ⤒㊰ࡢ୍ࡘࡀேᕤ≀ࡢ⁻╔࡛࠶ࡿྍ⬟ᛶࢆ♧၀ࡋ࡚࠸ࡿࠋ

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3-2-2㸬ᗏ⏕⏕≀㸦ᗏ㉁୰௨እ㸧

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ࣄࢻࣟ⹸㢮 3 ✀ࠊࣄ࣒ࣛࢩ㢮 1 ✀ࠊ㈅㢮 14 ✀㸦࠺ࡕ 7 ✀ࡣᗂ㈅㸧
ࠊከẟ㢮 8 ✀ࠊ࣍ࢩ࣒ࢩ㢮 1 ✀ࠊ࣑࢘ࢢࣔ㢮➼ᑠᆺࡢ⠇㊊ື≀ 5 ✀ࠊࣇࢪࢶ࣎㢮 2 ✀ࠊ࢚ࣅ࣭࢝ࢽ㢮 13 ✀ࠊࢥࢣ࣒ࢩ㢮 14 ✀ࠊ࢘ࢽ㢮 2 ✀ࠊ㨶㢮 1 ✀ࡀ☜ㄆࡉࢀࡓ㸦⾲ 3-2㹼3-4ࠊᅗ 12-1ࠊ12-2㸧ࠋᾏᗏࡢᒾ▼ୖ࡟≉࡟௜╔ᩘࡀከ࠿ࡗࡓࡶࡢࡣࣄࢻࣟ⹸㢮࡜ࢥࢣ࣒ࢩ㢮࡛࠶ࡗࡓࠋࡇࢀࡽࡣᾏᗏ
ࡢ〄ᆅ࡟࠾ࡅࡿ⩌㞟ᙧᡂࡢึᮇ࡟ຍධࡍࡿศ㢮⩌࡛࠶ࡿࡇ࡜࠿ࡽࠊ௒ᅇほᐹࡋࡓすஅᓥ࿘㎶ࡢᾏᗏ⎔ቃࡣࠊ⩌㞟ࡢ෌⏕ึᮇࡢ≧ែ࡛࠶ࡿ࡜⪃࠼ࡽࢀࡿࠋࡇࡢ࠺ࡕࠊࣄࢻࣟ⹸㢮࡟ࡘ࠸࡚ࡣࠊࢩࣟ࢞ࣖᒓࡢ୍✀㸦Aglaophenia sp.㸧ࠊࣁࢿ࢞ࣖᒓࡢ୍✀㸦Plumlaria sp.㸧ࠊ࣍ࢯ࢞ࣖᒓࡢ୍✀㸦Halecium sp.㸧࡛࠶ࡾࠊ௜╔ࡋ࡚࠸ࡿᒾ࡞࡝࡟ࡣࢫࢫ࢟㔝ཎࡢࡼ࠺࡟୍㠃࡟ࢥࣟࢽ࣮ࢆᙧᡂࡋ࡚࠸ࡓࠋࡲࡓࠊࢥࢣ࣒ࢩ㢮ࡣྜࢃࡏ࡚ 13 ✀ࡀᒾ⾲㠃࠿ࡽᚓࡽࢀ࡚࠾ࡾࠊ
≉࡟ࢡࢲࢥࢣ࣒ࢩ⛉ࡢ୍✀㸦Tubulipora spp.࠾ࡼࡧ Exidmonea sp.㸧ࠊࣁࢢࢳࢥࢣ࣒ࢩ⛉ࡢ୍✀㸦Pleurocodonellina sp.㸧ࠊ࣑࢝ࢯࣜࣁ࢖ࢥࢣ࣒ࢩ㏆ఝ✀㸦Aetea sp.㸧ࠊ࣑ࢧ࢟࢔࣑ࢥࢣ࣒ࢩ
㏆ఝ✀㸦Reteporellina cf. denticulata㸧࡞࡝ࡀከࡃᚓࡽࢀࡓࠋࢥࢣ࣒ࢩ࡛ࡣࡇࡢ࡯࠿࡟ࠊ࢝ࢢ
ࢶࢳࢥࢣ࣒ࢩᒓࡢ୍✀㸦Rhynchozoon sp.㸧ࠊࣔࣟࢸࢥࢣ࣒ࢩ⛉ࡢ୍✀㸦Hippomenella sp.㸧ࠊ࢖ࢱࢥࣈࢥࢣ࣒ࢩ⛉ࡢ୍✀㸦Drepanophora sp.㸧ࠊ࣑ࢬ࢝࢟ࢥࢣ࣒ࢩࡢ୍✀㸦Escharina sp.㸧ࠊ
Triticella ᒓࡢ୍✀㸦Triticella sp.㸧ࡶᚓࡽࢀࡓࠋࡇࡢ࠺ࡕࣁࢢࢳࢥࢣ࣒ࢩ⛉ࡢ୍✀ࡸ࣑ࢧ࢟− 119 −

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࢔࣑ࢥࢣ࣒ࢩ㏆ఝ✀ࠊ࢖ࢱࢥࣈࢥࢣ࣒ࢩ⛉ࡢ୍✀ࠊ࣑ࢬ࢝࢟ࢥࢣ࣒ࢩࡢ୍✀ࡣࠊ ᬮ࡞ᾏᇦ࡟⏕ᜥࡍࡿ༡᪉✀࡜ࡋ࡚ࡶ▱ࡽࢀࡿࠋࡲࡓࠊTriticella ᒓࡢ୍✀࡟ࡘ࠸࡚ࡣࠊಶ⹸ࡢ኱ࡁࡉࠊゐᡭᩘࠊ࠾ࡼࡧᅛ╔ᇶ㉁࠿ࡽࠊᮍグ㍕✀࡛࠶ࡿ࡜⪃࠼ࡽࢀࡿࠋ㉳❧ᛶࡢ✀࡟ࡘ࠸࡚ࡣࠊ
ࡑࢀࡽࡢ⩌యࡢᢡࢀࡓ◚∦ࡀ┤ୗࡢᾏᗏᇶ㉁୰࠿ࡽࡶ☜ㄆࡉࢀ࡚࠾ࡾࠊࡇࢀࡽࡀᚋ㏙ࡢᾋ㐟ᛶ㈅㢮ࡢṚẆ࡜࡜ࡶ࡟ࠊⅆᒣ⅊ࡸࢫࢥࣜ࢔࡛ࡢࡳᙧᡂࡉࢀ࡚࠸ࡓᾏᗏࡢᇶ㉁ࡢከᵝᛶᙧᡂ࡟ࡶᐤ୚ࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋ࡞࠾ࠊᾏᗏࡢ⏕≀ࢧࣥࣉࣝ୰࠿ࡽࡣࠊ」ᩘಶయࡢ࢖࣎
࣑࢘ࢢࣔ⛉ࡢ୍✀ࡶᚓࡽࢀࡓࠋ࣑࢘ࢢࣔࡢ୰࡟ࡣ่⬊ື≀ࡸࢥࢣ࣒ࢩ㢮ࢆᤕ㣗ࡍࡿࡶࡢࡶ
Ꮡᅾࡍࡿࡇ࡜࠿ࡽࠊࡇࢀࡽࡣㄪᰝᾏᇦࡢ⎔ቃ୰࡟㇏ᐩ࡟Ꮡᅾࡍࡿࣄࢻࣟ⹸㢮ࡸࢥࢣ࣒ࢩ㢮ࢆ㣵ᩱ࡜ࡋ࡚ᤕ㣗ࡋ࡚࠸ࡿྍ⬟ᛶࡶ⪃࠼ࡽࢀࡿࠋࣚࢶࣁ࢖ࢩ࢞ࢽ࡜ࣄ࣓࣋ࢽࢶࢣ࢞ࢽࡣᑠ
➟ཎㅖᓥ࿘㎶ᾏᇦ࡛ࡣࠊึࡵ࡚☜ㄆࡉࢀࡓࠋ࠸ࡎࢀࡶ࢖ࣥࢻ࠿ࡽすኴᖹὒ࡟ᗈࡃศᕸࡍࡿ

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ᬑ㏻✀࡛࠶ࡿࠋ㈅㢮ࡣᑠ➟ཎㅖᓥ࿘㎶࡛ᬑ㏻࡟ぢࡽࢀࡿࡶࡢࡀከ࠿ࡗࡓࠋ

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3-2-3㸬ᗏ㉁୰ࡢ⏕≀

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᭷Ꮝ⹸ 1 ✀ࠊ⥺⹸㢮 2 ✀ࠊከẟ㢮 3 ✀ࠊ࣍ࢩ࣒ࢩ㢮 1 ✀ࠊࢯࢥ࣑ࢪࣥࢥ㢮 4 ✀ࠊࢥࢣ࣒ࢩ㢮 2 ✀ࠊ࢘ࢽ㢮 2 ✀ࠊ㨶㢮 1 ✀ࡀ☜ㄆࡉࢀࡓ㸦⾲ 3-5ࠊᅗ 13ࠊ14㸧ࠋᗏ⏕᭷Ꮝ⹸㢮ࡣ St.S2
ࡢ 32μm ௨ୖࡢศ⏬࡟࠾࠸࡚࣮ࣟࢬ࣋ࣥ࢞ࣝ࡟ᰁⰍࡉࢀ࡚࠸࡞࠸ Rosalina globularis ࡀ 2ಶయ☜ㄆࡉࢀࡓࠋࡇࢀࡣࠊ୍⯡ⓗ࡞ሁ✚≀࡜ẚ㍑ࡋ࡚᭷Ꮝ⹸ᐦᗘ࡜ከᵝᛶࡀప࠸ࠋRosalinaᒓࡣ⸴㢮ࡢⴥୖࡸᒾ▼⾲㠃࡞࡝࡟௜╔ࡋ࡚⏕άࡋ࡚࠸ࡿ✀㢮࡛࠶ࡾࠊSt.S2 ࡢ◁ࡀࡕ࡞ሁ✚≀࡛ࡣ࠶ࡲࡾぢࡽࢀ࡞࠸ࡇ࡜ࠊ᭷ᶵ≀࡟཯ᛂࡍࡿ࣮ࣟࢬ࣋ࣥ࢞ࣝ࡟ࡼࡿᰁⰍࡀぢࡽࢀ࡞࠸ࡇ࡜࠿ࡽࠊ␗࡞ࡿᆅⅬ࠿ࡽὶࢀ㎸ࢇࡔ㑇㧁ࡢྍ⬟ᛶࡶྰᐃ࡛ࡁ࡞࠸ࠋࡍ࡞ࢃࡕࠊ௒ᅇࡢ
St.S2 ࠿ࡽࡣ⏕ࡁࡓ᭷Ꮝ⹸ࡀ᳨ฟ࡛ࡁ࡞࠿ࡗࡓྍ⬟ᛶࡀ㧗࠸ࠋ௒ᅇࡢ₯ỈㄪᰝᆅⅬࡣ௨๓࡟ẚ࡭ࡿ࡜኱ᖜ࡟Ỉ῝ࡀὸࡃ࡞ࡗ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡿࡇ࡜࠿ࡽࠊ᭱㏆࡟࡞ࡗ࡚ሁ✚ࡋࡓⅆᒣᄇฟ≀࡛࠶ࡾࠊ᭷Ꮝ⹸ࡣᮍຍධࡢ≧ែࢆᤊ࠼࡚࠸ࡿ࡜⪃࠼࡚࠸ࡿࠋ௒ᚋࠊࣔࢽࢱࣜࣥࢢ
ࢆ⤒ᖺⓗ࡟ᐇ᪋ࡍࡿࡇ࡜࡛ࠊ᭷Ꮝ⹸ࡀ࠸࡞࠸≧ែ࠿ࡽࠊ࡝ࡢࡼ࠺࡟ኚ㑄ࡋ࡚࠸ࡃ࠿ࢆ㏣㊧ㄪᰝ࡛ࡁࡿ࡜⪃࠼ࡽࢀࡿࠋ௒ᚋࡣࠊ௒ᅇᚓࡽࢀࡓ St.S2 ௨እࡢヨᩱࡶヲ⣽࡟ㄪ࡭ࡿணᐃ࡛
࠶ࡿࠋᚓࡽࢀࡓࢧࣥࣉࣝࡢከࡃ࡛ࠊࢯࢥ࣑ࢪࣥࢥ㢮ࠊ㈅ᙧ⹸㢮ࠊࣀࣛࣜ࢘ࣟࢥ࣒ࢩ⛉ࡢPisione ᒓ㸦㛫㝽ᛶከẟ㢮㸧࠾ࡼࡧࢧࢩࣂࢦ࢝࢖⛉ࡸ࢘ࣟࢥ࣒ࢩள┠࡟ᒓࡍከẟ㢮ࠊࢡ࣐ࣟࢻࣛ┠ࡢ⮬⏤⏕άᛶࡢ⥺⹸㢮㸦Draconematidae ⛉࡯࠿㸧ࡀࡳࡽࢀࡓࠋࡇࡢ࡯࠿ࠊ஧ᯛ㈅ࡢ⛶㈅ࡸᑠᆺࡢᕳ㈅㢮ࡢẆ㸦ᾋ㐟ᛶᕳ㈅㢮ࡢẆࡶྵࡴ㸧ࡶᚓࡽࢀࡓࠋࡇࡢࡇ࡜࠿ࡽࠊᗏ㉁ࡢ㛫㝽⎔ቃ࡟࠾࠸࡚ࡣࠊࡇࢀࡽࡢ⏕≀ࡀ⩌㞟෌⏕ࡢẚ㍑ⓗึᮇࡢẁ㝵࡛ຍධࡋ࡚࠸ࡿࡇ࡜
ࡀ᫂ࡽ࠿࡜࡞ࡗࡓࠋPisione ᒓࡣ㛫㝽⎔ቃ࡟࠾ࡅࡿ௚ࡢ㛫㝽⏕≀ࡢᤕ㣗⪅࡛࠶ࡿ࡜⪃࠼ࡽࢀ࡚࠸ࡿࡇ࡜࠿ࡽࠊࡇࢀࡽࡀከࡃࡢࢧࣥࣉࣝ୰࡛ᚓࡽࢀࡓࡇ࡜ࡣࠊ㣵ᩱ࡜࡞ࡿ⏕≀ࡀ㇏ᐩ࡟Ꮡᅾࡍࡿࡇ࡜ࢆ♧၀ࡍࡿ࡜⪃࠼ࡽࢀࡿࠋࡲࡓࠊࡇࡢ࡯࠿࡟ㄪᰝ᫬࡟኱ᆺಶయࡀ☜ㄆ࡛ࡁ࡞࠿ࡗࡓᲲ⓶ື≀࡟ࡘ࠸࡚ࡶࠊᩘ✀ࡢ⛶࢘ࢽࡀᚓࡽࢀࡓࡇ࡜࠿ࡽࠊࡇࢀࡽࡢᗂ⏕ࡣすஅᓥ࿘㎶ᾏᇦ࡟ࡶ฿㐩࣭╔ᗏࡋ࡚࠾ࡾࠊ௒ᚋࠊ㣵ᩱ⎔ቃࡀᨵၿࡉࢀࢀࡤࡑࢀࡽࡀᡂ㛗ࡋᐃ╔ࡋ࡚࠸ࡃ࡜⪃࠼ࡽࢀࡿࠋ኱ᆺࡢ⸴㢮ࡸ㐀♋ᛶࡢࢧࣥࢦ㢮ࡀࡳࡽࢀ࡞࠸ࡇ࡜࠿ࡽࠊㄪᰝᾏᇦ࡟࠾

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ࡇ࡜࠿ࡽࠊࡇࢀࡽࡢ⏕≀ࡢᐃ╔࡟࡜ࡗ࡚༑ศ࡞᫬㛫ࡀ⤒㐣ࡋ࡚࠸࡞࠸ࡇ࡜ࠊ࠾ࡼࡧࡑࢀࡽ
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すஅᓥࡢᾏᓊ⥺࠿ࡽ⣙ 1 ࢟ࣟ㞳ࢀࡓ࿘ᅖࡢ 8 ᪉఩࡛ࡢ༗๓୰࡛ࡢࢧࣥࣉࣜࣥࢢ࠾ࡼࡧすஅᓥᮾഃ࡛ࡢ᪥ἐ 1 ᫬㛫ᚋࡢࢧࣥࣉࣜࣥࢢ࡟࠾࠸࡚ࠊ᭷᷸ື≀㛛 1 ✀ࠊ่⬊ື≀㛛 11 ✀ࠊ⎔ᙧື≀㛛 19 ✀ࠊ㌾యື≀㛛 11 ✀ࠊ⠇㊊ື≀㛛 38 ✀ࠊẟ㢡ື≀㛛 4 ✀ࠊ⬨⣴ື≀㛛 10✀ࠊࡑࡢ௚ྵࡵ࡚ 105 ✀௨ୖ㸦࠺ࡕᗏ⏕⏕≀ࡢᗂ⏕ࡣ 25 ✀㸧ࡀ☜ㄆࡉࢀࡓ㸦⾲ 4ࠊᅗ 15㸧ࠋ⾲ 2ࠊ⾲ 4 ࡟ࡣࠊ࠶ࡿ⛬ᗘྠᐃࡀ㐍ࢇࡔ✀ࡢࡳᥖ㍕ࡋࡓࠋ᪥୰ࡢࢧࣥࣉࣜࣥࢢ࡟࠾࠸࡚ࡣࠊ໭࠿ࡽ໭すࡲ࡛᫬ィᅇࡾ࡟ 8 ᪉఩࡟࠾࠸࡚ࠊࡑࢀࡒࢀ
21, 23, 25, 27, 33, 35, 27, 36 ✀ࡢ⏕≀ࡀ☜ㄆࡉࢀࠊすഃ༙ศ࡛⏕≀ࡢ✀ࡀከࡃぢࡽࢀࡓࠋࡇࡢ࡜ࡁࠊすഃ༙ศ࡟࠾࠸࡚ࡣࠊỈ ࡀᮾഃࡼࡾࡶపࡃࠊすᆅⅬ࡟࠾࠸࡚Ỉ῝ 20m ࡛⾲ᒙࡼࡾࡶ 3Υప࠸ᾏỈࡀୖࡀࡗ࡚ࡁ࡚࠸ࡓࡓࡵࠊࡑࡢ୧ഃ࡛⏕≀✀ࡀከࡃ࡞ࡗࡓ࡜⪃࠼ࡽࢀࡿࠋࡲࡓࠊ᪥୰ࡢᖹᆒฟ⌧✀ᩘࡀ⣙ 28 ✀࡛࠶ࡗࡓࡀࠊ᪥ἐᚋ࡟࠾࠸࡚ࡣ 48 ✀ぢࡽࢀࠊ࣓࢚ࣘࣅ㢮ࡸ᪥୰࡟ࡣぢࡽࢀ࡞࠿ࡗࡓ㈅ᙧ㢮ࡀከࡃぢࡽࢀࡓࠋ⥲ィ࡛⣙ 4,200 ಶయᚓࡽࢀࡓ
ࡀࠊࡑࡢ࠺ࡕᗏ⏕⏕≀ࡢᗂ⏕ࡣࠊከẟ㢮ࡀ 1.02㸣ࠊ㌾యື≀㛛ࡀ 0.24%ࠊ⏥Ẇ㢮ࡢ㛗ᑿ㢮ࠊ␗ᑿ㢮ࠊ▷ᑿ㢮ࡢᗂ⏕ࡀ 0.24%࡛࠶ࡗࡓࠋすஅᓥ࡬ࡣ₻ὶ࡟ࡼࡾᗏ⏕⏕≀ࡢᗂ⏕ࡀ㐠ࡤࢀ࡚ࡁ࡚࠸ࡿࡇ࡜ࡀᮏㄪᰝ࡛☜ㄆ࡛ࡁࡓࠋࡋ࠿ࡋࠊすஅᓥ࿘㎶ᾏᇦࡣࠊ᪥୰࡟࠾࠸࡚ࡣ඲࡚
ࡢື≀ࣉࣛࣥࢡࢺࣥࢆ࠶ࢃࡏ࡚ࡶ⣙ 1,000 ಶయ࣭m-3 ࡜⏕≀㔞ࡀ㠀ᖖ࡟ᑡ࡞ࡃࠊ㈋ᰤ㣴≧ែ࡛࠶ࡾࠊᗏ⏕⏕≀ࡢᗂ⏕ࡣࡑࡢ࠺ࡕࡢ 1.5㸣࡟ࡍࡂ࡞࠸ࠋࡇࡢࡇ࡜࠿ࡽࠊすஅᓥ࡬ࡢᗏ⏕⏕≀ࡢຍධ࡜ᐃ╔࡟ࡘ࠸࡚ࡣ᫬㛫ࡀ࠿࠿ࡿ࡜ᛮࢃࢀࠊ௒ᚋࡢࣔࢽࢱࣜࣥࢢࡢ㔜せᛶࡀ࠺࠿ࡀࢃࢀࡓࠋࡋ࠿ࡋࠊ2020 ᖺ 7 ᭶ࡢ኱つᶍᄇⅆᚋ࡟࠾࠸࡚ࡶࠊすஅᓥ࿘㎶ࡢ῝࠸ሙᡤ࡟ࡣࠊ
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෗┿࠾ࡼࡧᫎീࡢ᧜ᙳ࡟ࡼࡾࠊ㨶㢮ࡣ 49 ✀☜ㄆࡉࢀࡓ㸦⾲ 5ࠊᅗ 16㸧ࠋすஅᓥ࡛௒ᅇ☜ㄆࡉࢀࡓ✀ࡣ඲✀㢮ᑠ➟ཎㅖᓥ࡛グ㘓ࡀ࠶ࡿ✀ࡔࡗࡓ㸦ᒸᮧ࣭ᑽᒸࠊ2007㸹୰ᆓࠊ2013㸹ᑠ➟ཎ⮬↛ᩥ໬◊✲ᡤࠊ2017㸧ࠋࡓࡔࡋࠊ㔝ཱྀ࡯࠿㸦2023㸧࡟ࡼࡿ AUV ࡢㄪᰝ࡛᧜ᙳࡉࢀ
ࡓᫎീ࡟ࡶ㨶㢮ࡀ᧜ᙳࡉࢀ࡚࠾ࡾࠊ௒ᚋゎᯒࡀᚲせ࡛࠶ࡿࠋ

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3-3㸬すஅᓥ࿘㎶ᾏᇦ࡟ὶࢀ╔ࡃ⁻ὶ≀๓㏙ࡢ㏻ࡾࠊすஅᓥࡣ୍␒㏆࠸∗ᓥ࠿ࡽ 130km 㞳ࢀ࡚࠸ࡿࡀࠊ5 ᪥㛫ࡢㄪᰝ୰࡟ 6 ಶࡢ⁻╔≀ࡀ᥇ྲྀࡉࢀࡓ㸦ᅗ 17㸧
ࠋ⁻╔≀࡟ࡣࠊ⸴㢮 2 ✀ࠊ࢖ࢯࢠࣥࢳࣕࢡ 1 ✀ࠊࣄ࣒ࣛࢩ㢮
1 ✀ࠊ㈅㢮 5 ✀ࠊከẟ㢮 4 ✀ࠊ࣍ࢩ࣒ࢩ㢮 1 ✀ࠊ࢚࣎ࢩ࢞࢖ 1 ✀ࠊࣚࢥ࢚ࣅ➼ᑠᆺࡢ⏥Ẇ
㢮 4 ✀ࠊ࢝ࢽ㢮 3 ✀ࠊ㨶㢮 4 ✀ࡀ☜ㄆࡉࢀࡓࠋࡑࡢ࡯࠿ࠊࢩ࢔ࣀࣂࢡࢸࣜ࢔࡜ᛮࢃࢀࡿ✀ࡶ☜ㄆࡉࢀࡓ㸦⾲ 6-1㹼6-5㸧
ࠋ⁻ὶ≀ୖ࡛☜ㄆࡉࢀࡓ࢜࢟ࢼ࢞ࣞ࢞ࢽࠊࣄࢤࢼ࢞ࣚࢥ࢚ࣅ
⛉ᩘ✀㸦ࢽࢵ࣏ࣥࣔࣂࣚࢥ࢚ࣅ㏆ఝ✀࡞࡝㸧ࠊ࢘ࣟࢥ࣒ࢩ⛉ࡸ࣑࢘ࢣ࣒ࢩ⛉ࠊࢧ࣓ࣁࢲ࣍
ࢩ࣒ࢩ⛉ࡢ⎔ᙧື≀ࠊ࠸ࡃࡘ࠿ࡢᑠᆺࡢ㈅㢮㸦஧ᯛ㈅࠾ࡼࡧᕳ㈅㸧
ࠊࣄ࣒ࣛࢩ㢮࡞࡝ࡢ࠺ࡕ࠸ࡃࡘ࠿ࡣ⁻ὶ≀ࢆ᳇ࡳᐙ࡜ࡋ࡚⏝࠸ࡿࡇ࡜ࡀ▱ࡽࢀ࡚࠸ࡿࠋࡲࡓࠊᅛ╔ᛶࡢື≀࡜ࡋ࡚ࠊ࢚࢝ࣝ࣎ࢩ㸦Lepas (Anatifa) anserifera㸧ࠊࢳࢠࣞ࢖ࢯࢠࣥࢳࣕࢡ㏆ఝ✀㸦Exaiptasia cf.
pallida㸧ࠊࢧ࣓ࣁࢲࢥࢣ࣒ࢩᒓࡢ୍✀㸦Jellyella eburnea ㏆ఝ✀㸧ࡀᚓࡽࢀࡓࠋࡇࢀࡽࡣ࠸
ࡎࢀࡶ⁻ὶ≀ୖ࡟ࡳࡽࢀࡿࡇ࡜ࡀࡼࡃ▱ࡽࢀࡓ✀࡛࠶ࡿࠋࡇࡢ࠺ࡕࢧ࣓ࣁࢲࢥࢣ࣒ࢩᒓࡢ
୍✀㸦Jellyella eburnea ㏆ఝ✀㸧ࡣୡ⏺୰ࡢ⁻ὶ≀ୖ࠿ࡽሗ࿌ࡀ࠶ࡿ✀࡛ࠊᾋ㐟ᛶ㈅㢮ࡸᾏ⸴㢮ࡢ࡯࠿ࠊࢽ࣮ࣗࢪ࣮ࣛࣥࢻ࡛ࡣࣉࣛࢫࢳࢵࢡ࣎ࢺࣝୖ࠿ࡽࡢሗ࿌ࡶ࠶ࡿࠋᮏ✀ࡣࡇࢀࡲ࡛ᅜෆ࠿ࡽࡢṇᘧ࡞ሗ࿌ࡣ࡞࠸ࡀࠊࡑࡢศᕸᇦ࠿ࡽすஅᓥ࿘㎶ࡢ⁻ὶ≀ୖ࡟࠾࠸࡚ࡶ
ᬑ㏻࡟ࡳࡽࢀࡿࡶࡢ࡜⪃࠼ࡽࢀࡿࠋ㈅㢮ࡣ࢘࢟ࢶ࣎࡞࡝ᗈᇦศᕸ✀ࡀ☜ㄆࡉࢀࡓࠋ௒ᅇᚓ
ࡽࢀࡓ⁻ὶ≀ୖࡢ⏕≀┦ࡣ⁻ὶ≀࡟≉᭷ࡢࡶࡢࡀከࡃࡳࡽࢀࡓࠋࡇࢀࡽ⁻ὶ≀࡟ࡼࡿすஅᓥἢᓊᇦ࡬ࡢຍධࡀࠊすஅᓥ࿘㎶ᾏᇦࡢᗏ⏕⏕≀┦࠾ࡼࡧࡑࡢ⩌㞟ᙧᡂ࡟࡝ࢀ࡯࡝ࡢᙳ㡪ࢆཬࡰࡍࡢ࠿ࠊ௒ᚋࡢᐃᮇⓗ࡞ࣔࢽࢱࣜࣥࢢ࡟ࡼࡾ᫂ࡽ࠿࡟࡞ࡿࡶࡢ࡜ᛮࢃࢀࡿࠋ
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3-4㸬⎔ቃ DNA ࢽࢩࣀࢩ࣐࣍࢘࢟࢞ࢽࡢ㑇ఏᏊ᝟ሗࡣ࡞࠸ࡓࡵࠊࢽࢩࣀࢩ࣐࣍࢘࢟࢞ࢽࡢࢩࣀࢽ࣒࡛࠶
ࡿྍ⬟ᛶࡢ㧗࠸ࢱ࢖࣡ࣥ࣍࢘࢟࢞ࢽࡢ㑇ఏᏊ᝟ሗࢆ⏝࠸࡚ࠊࣉࣛ࢖࣐࣮ࢆస〇ࡋࡓࠋࡋ࠿
ࡋࠊ⎔ቃ DNA ࢧࣥࣉ࡛ࣝࡢ㝧ᛶ཯ᛂࡣ⌧ẁ㝵࡛ࡣᚓࡽࢀ࡚࠸࡞࠸ࠋࢽࢩࣀࢩ࣐࣍࢘࢟࢞
ࢽࡣ⇕Ỉᇦ࡟ࡋ࠿⏕ᜥࡋ࡞࠸ࠋ௒ᅇࡢㄪᰝ࡛ࡣࠊ⇕Ỉࡢฟ࡚࠸ࡿᆅᇦࡀไ㝈༊ᇦෆ࡟ධࡗ
࡚࠸ࡓࡓࡵࠊࡑࡢ⎔ቃỈࢆ┤᥋ᚓࡽࢀ࡞࠿ࡗࡓࡢࡀཎᅉ࠿࡜ᛮࢃࢀࡿࠋࡲࡓࠊ୍᪉࡛ࢽࢩ
ࣀࢩ࣐࣍࢘࢟࢞ࢽࡀࡲࡔᐃ╔ࡋ࡚࠸࡞࠸ྍ⬟ᛶࡶ࠶ࡿࠋࢱ࢖࣡ࣥ࣍࢘࢟࢞ࢽࡣᘧ᰿ᓥࡢỈ῝ 15m ࡟࠶ࡿᾏᗏ Ἠ࡛ぢࡘ࠿ࡗ࡚࠾ࡾࠊᘧ᰿ᓥࡢ໭ᮾἈࠊỈ῝ 200㹫࡟࠶ࡿ኱ᐊࡔࡋ࡟
ࡶࢱ࢖࣡ࣥ࣍࢘࢟࢞ࢽࡀ⏕ᜥࡋ࡚࠸ࡿ㸦Miyake et al., 2019㸧ࠋࡇࢀࡽ 2 ᆅⅬ࠿ࡽ᥇ྲྀࡋࡓ࣍
࢘࢟࢞ࢽࡢ㑇ఏᏊゎᯒࢆ⾜࠺࡜ࠊࡇࢀࡽࡢಶయ⩌㛫࡛㑇ఏⓗ஺ὶࡀ࠶ࡿࡇ࡜ࡀ᫂ࡽ࠿࡟࡞
ࡗ࡚࠸ࡿ㸦Oda et al., 2023㸧
ࠋࡇࡢࡇ࡜ࡶ⪃៖࡟ධࢀࡿ࡜ࠊすஅᓥ༡ᮾ㒊ࡢỈ῝ 200m ⛬ᗘࡢ࡜ࡇࢁ࡟ࡣ࢝ࣝࢹࣛࡀ࠶ࡾࠊࡑࡇ࡟ࡣ⇕Ỉࡀᄇ࠸࡚࠸ࡿྍ⬟ᛶࡀ༑ศ࡟࠶ࡿࡓࡵࠊࡑࡇ
࡟ࢽࢩࣀࢩ࣐࣍࢘࢟࢞ࢽࡀ⏕ᜥࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋ௒ᚋࠊすஅᓥἢᓊࡢ࣍࢘࢟࢞ࢽࡣ
⤯⁛ࡋࡓ࡜ࡋ࡚ࡶࠊࢽࢩࣀࢩ࣐࣍࢘࢟࢞ࢽࡣᾏᗏ࢝ࣝࢹࣛࡢ⇕Ỉᇦ࡟⏕ᜥࡋ࡚࠾ࡾࠊࡑࡇ
࠿ࡽᗂ⏕ࡀศᩓࡋ࡚すࣀᓥἢᓊ࡟ᐃ╔ࡍࡿࡶࡢ࡜ᛮࢃࢀࡿࠋࢱ࢖࣡ࣥ࣍࢘࢟࢞ࢽࡢ⏘༸᫬ᮇࡣึኟ࠿ࡽ⛅࡛࠶ࡿࡇ࡜࠿ࡽࠊ2020 ᖺ 7 ᭶ࡢ኱つᶍᄇⅆᚋ࡟ᗂ⏕ࡀຍධࡍࡿ᫬㛫ࡀ↓࠿

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4-1㸬すஅᓥ࿘㎶ᾏᇦࡢᾏᗏᆅᙧࡢኚ໬࡜ᾏὒ⎔ቃ ௒ᅇ₯Ỉㄪᰝࢆ⾜ࡗࡓ࣏࢖ࣥࢺࡣࠊ඲࣏࢖ࣥࢺ࡛Ỉ῝ࡀ 2017 ᖺࡼࡾࡶ 10㹼20m ⛬ᗘὸࡃ࡞ࡗࡓྍ⬟ᛶࡀ࠶ࡾࠊࡑࡢࡼ࠺࡞ሙᡤ࡛ࡣࠊᄇฟ≀ࡢὶධ࠾ࡼࡧ㝆ࡾ✚ࡶࡾ࡟ࡼࡾࠊ2020
ᖺࡢᄇⅆ๓ࡢᾏᗏࡢ⏕≀┦ࡣ୍ᤲࡉࢀࡓ࡜᥎ ࡉࢀࡿࠋ୍᪉ࠊ᥇Ἶㄪᰝࢆ⾜ࡗࡓ 50m ௨῝ࡢ࣏࢖ࣥࢺࡣࠊ2017 ᖺ࠿ࡽỈ῝ࡢኚ໬ࡣ࠶ࡲࡾ࡞࠿ࡗࡓ࡜ᛮࢃࢀࡿࡀࠊ2019 ᖺ௨๓ࡢᾏᗏࡢᵝᏊ࡟ࡘ࠸࡚ᾏᗏᆅᙧᅗ௨እࡢグ㘓ࡀṧࡗ࡚࠸࡞࠸ࡓࡵࠊ᥎ ࡢᇦࢆฟ࡞࠸ࠋᮏㄪ
ᰝ࡟ࡼࡾࠊすஅᓥ࿘㎶ࡢỈ㉁ࡣࠊኚⰍᇦࡢཎᅉ࡜ᛮࢃࢀࡿᓥ࠿ࡽࡢὶฟ≀ࡢᏑᅾࢆ㝖ࡃ࡜୍⯡ⓗ࡞ள⇕ᖏࡢᓥࠎ࿘ᅖࡢᾏὒ⎔ቃ࡜ྠᵝ࡛࠶ࡿࡇ࡜ࡀ♧၀ࡉࢀࡓࠋ
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4-2㸬すஅᓥ࿘㎶ᾏᇦࡢ⏕≀┦ ୺࡟ㄪᰝࢆ⾜ࡗࡓすஅᓥࡢ໭㒊ࡢᾏᇦ࡛ࡣࠊᒾ▼ୖ࡟ࡣ∗ᓥิᓥࠊẕᓥิᓥ➼࡛ඃ༨ࡋ࡚࠸ࡿࢧࣥࢦ㢮ࡣぢࡽࢀ࡞࠿ࡗࡓࠋࢧࣥࢦ㢮࡟㛵ࡋ࡚ࡣࠊ2020 ᖺࡢすஅᓥࡢ኱つᶍ࡞ᄇⅆ࡟ࡼࡗ࡚ࠊすஅᓥࡢᾏᗏࡶ୍ᤲࡉࢀࡓࡀࠊࡑࡢ᫬ᮇࡀ 7 ᭶࡛࠶ࡾࠊࢧࣥࢦ㢮ࡢ⦾Ṫࢩ࣮ࢬࣥࡀ⤊ࢃࡗࡓᚋ࡛࠶ࡗࡓࡢ࡛ࠊ2021 ᖺ௨㝆࡟⦾Ṫࡋࡓᗂ⏕ࡀຍධࡍࢀࡤࠊ௒ᚋ┠࡟ࡘࡃࡼ࠺࡟࡞ࡿ࡜ᛮࢃࢀࡿࠋࡲࡓࠊ⸴㢮ࡸᾏ⥥㢮ࠊ࣍ࣖ㢮࡞࡝ࡢ኱ᆺࡢ⏕≀ࡶぢࡽࢀࡎࠊᒾ▼ୖࡣࣄࢻࣟ⹸㢮࡜ࢥࢣ࣒ࢩ㢮࡛そࢃࢀ࡚࠸ࡓࠋ◁Ἶ୰࡟ࡣࠊࢦ࢝࢖㢮ࠊ᭷Ꮝ⹸࡞࡝ࡀⓎぢࡉࢀ࡚࠸ࡿࡀࠊࡑࡢᩘࡣᑡ࡞ࡃࠊ࢘ࢽ㢮ࡣ☜ㄆࡉࢀࡓࡀ 2 ಶయࡢࡳ࡛ࠊࣄࢺࢹ㢮ࠊࢼ࣐ࢥ㢮ࡣ☜ㄆࡉࢀ࡞࠿ࡗࡓࠋ㈅㢮ࠊ኱ᆺࡢ⏥Ẇ㢮ࡶ✀ࡢከᵝᛶࡀప࠸ࠋ୍᪉࡛ࠊࣉࣛࣥࢡࢺࣥ㢮ࡢ୰࡟ࡣࠊࢡ࣐࢚ࣝࣅ㢮ࠊከẟ㢮ࠊࣄࢺࢹ㢮࡞࡝ࡢ࣋ࣥࢺࢫࡢᗂ⏕ࡀ☜ㄆࡉࢀ࡚࠾ࡾࠊ௒
ᚋᗏ⏕⏕≀ࡢከᵝᛶࡀ㧗ࡃ࡞ࡗ࡚࠸ࡃ࡜ᛮࢃࢀࡿࠋ㨶㢮ࡣ∗ᓥิᓥࠊẕᓥิᓥ➼࡜ẚ㍑ࡍ
ࡿ࡜✀ᩘࡀᑡ࡞࠸ࡶࡢࡢࠊྠᵝࡢ✀ࡀⓎぢࡉࢀࡓࠋ㨶㢮ࡣᑓ㛛ࡢㄪᰝࢆ⾜ࡗ࡚࠸࡞࠸ࡓࡵࠊ
☜ㄆᩘࡀᑡ࡞࠿ࡗࡓྍ⬟ᛶࡶ࠶ࡿࠋ ௨ୖࡼࡾࠊᮏㄪᰝ࡛ࡣࠊᾏὒᓥ࡟࠾ࡅࡿ⏕ែ⣔ࡢ୍ḟ㑄⛣ࡢึᮇẁ㝵ࢆグ㘓࡛ࡁࡓࠋ≉࡟⏕≀ࡢ⏕άᆺ࡟ࡼࡗ࡚ࠊࡑࡢฟ⌧ࡢᵝᏊࡀ㐪࠸ࠊ࣋ࣥࢺࢫ࡟㛵ࡋ࡚ࡣࠊࡲࡉ࡟㑄⛣ࡢึᮇẁ㝵ࢆほᐹ࡛ࡁࡓ࡜ᛮࢃࢀࡿࠋ୍᪉࡛ࠊࣉࣛࣥࢡࢺࣥࠊࢿࢡࢺࣥࡣࠊᄇⅆ࡟ࡼࡿ⁐ᒾࡸⅆᒣ⅊࡟そࢃࢀࡿᙳ㡪ࡀᑡ࡞ࡃࠊ࿘ᅖ࡟⏕ᜥࡋ࡚࠸ࡿࡶࡢࡀຍධࡋ࡚ࡁ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡓࠋすஅᓥࡢ኱つᶍᄇⅆᚋࡢᾏᇦࡢ⏕ែ⣔ࡣ✀ࡢከᵝᛶࡀపࡃࠊ㑄⛣ࡢึᮇࡢẁ㝵࡟࠶ࡿࠋ
1973 ᖺࡢᄇⅆࡢ⣙ 1 ᖺᚋ࡟⾜ࢃࢀࡓ 1974 ᖺࡢ಴⏣ࡽࡢㄪᰝ࡟ࡼࡾࠊᾏᗏࡢᄇ▼ୖ࡟ࢧࣥࢦࡢ⏕⫱ࡀほᐹࡉࢀ࡚࠸ࡿࡇ࡜࠿ࡽࡶ㸦Takeda & Kurata, 1977㸧
ࠊ௒ᚋすஅᓥࡢᄇⅆࡀⴠࡕ╔ࡅࡤᾏᇦࡢ⏕ែ⣔ࡢ㑄⛣ࡣẚ㍑ⓗ᪩ࡃ᥎⛣ࡍࡿྍ⬟ᛶࡀ⪃࠼ࡽࢀࠊ✀ᩘࡢቑຍࠊಶయᩘ
ࡢቑຍࡣ㡰ḟ㉳ࡇࡿࡶࡢ࡜᥎ ࡉࢀࡿࠋ
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4-3㸬すஅᓥ࿘㎶ࡢᾏὒ⏕≀┦ㄪᰝࡢ௒ᚋࡢᒎᮃ
ᮏㄪᰝࡣ▷ᮇ㛫ࡢㄪᰝ࡛࠶ࡗࡓࡀࠊᾏὒ⎔ቃࢆᢕᥱࡍࡿࡓࡵ࡟ࡣ࿘ᖺࡢㄪᰝࡀᚲせ࡟࡞ࡿࠋḟᅇࡢㄪᰝࡶᾏὒ⎔ቃࡢㄪᰝ࡜⏕≀┦ࡢㄪᰝࢆඹ࡟⥆ࡅࡿࡇ࡜࡟ࡼࡾࠊάືⓗ࡞ⅆᒣᓥࡀ࿘ᅖࡢᾏᇦࡢ⏕ែ⣔࡟୚࠼ࡿᙳ㡪࡟ࡘ࠸࡚ࠊ௒ᚋ᫂ࡽ࠿࡟࡞ࡗ࡚࠸ࡃࡶࡢ࡜♧၀ࡉࢀࡿࠋ⏕≀ࡢ᥇㞟᪉ἲ࡟ࡘ࠸࡚ࠊ࢚ࢡ࣐ࣥࣂ࣮ࢪ࡛ࡢ᥇㞟࠾ࡼࡧࡶࢇ࡝ࡾ࡛ࡢᤕ⋓ࡣすஅᓥ࡟࠾࠸࡚ࡣຠᯝⓗ࡛ࡣ࡞࠿ࡗࡓࠋᒾ▼ࡀከࡃࠊࡲࡓᾏᗏࡀ◁Ἶᗏ࡛࠶ࡗ࡚ࡶᑠ▼ࡀከࡃྵࡲࢀࠊ࢚ࢡ࣐ࣥࣂ࣮ࢪࡀ㛢ࡌᗏ㉁ࡀ᥇㞟࡛ࡁ࡞࠸ࡇ࡜ࡀከࡃ࠶ࡗࡓࠋࡲࡓࠊࡶࢇ࡝ࡾࢆኪ
㛫ᾏᗏ࡟㟼⨨ࡋࡓ࡜ࡇࢁࠊࢧ࣓࡜ᛮࢃࢀࡿ⏕≀࡟㱎ࡽࢀ࡚◚ቯࡉࢀࡓࠋすஅᓥ࡛ࡣ₯Ỉ࡟ࡼࡿ⏕≀┦ㄪᰝࡀ⾜ࢃࢀࡓグ㘓ࡀ࡞࠿ࡗࡓࡓࡵࠊᮏㄪᰝࡣᏳ඲⟶⌮ࢆ᭱ඃඛࡋ࡚ࡢㄪᰝ࡜
࡞ࡗࡓࠋすஅᓥ࿘㎶ࡣ᫬㛫ᖏ࡟ࡼࡗ࡚₻ࡢὶࢀࡀ㏿ࡃࠊ
7 ᭶ 10㹼12 ᪥ࡢ₯Ỉㄪᰝࡢᮇ㛫୰ࠊ₯Ỉ࡟㐺ࡋࡓ᫬㛫ᖏࡣ᪩ᮅࡢ‶₻᫬࠿ࡽ᫨ࡢୗࡆ₻ࡢ᫬㛫ᖏ࡟㝈ࡽࢀࡓࠋࡲࡓࠊᾏᗏࡢᆅ
ᙧ࠾ࡼࡧ₻ࡢὶࢀࡢ㏿ࡉࡢࡓࡵࠊ㘌ࡀ࠿࠿ࡾ࡟ࡃࡃࠊ኱ᆺ⯪ࢆ೵⯪࡛ࡁࡿ࣏࢖ࣥࢺࡶ㝈ࡽࢀ࡚࠸ࡓࠋᮏㄪᰝ࡛ࡣ₯Ỉ࡟㐺ࡋࡓሙᡤ࠾ࡼࡧ᫬㛫ᖏࡀ㝈ࡽࢀࡿࡶࡢࡢࠊᾏᗏࡢ⏕≀┦࡬ࡢᙳ㡪ࢆ᭱ᑠ㝈࡟ࡋ࡚ࠊ࠿ࡘຠ⋡ⓗ࡟ࢧࣥࣉࣝ᥇ྲྀࢆ⾜࠼ࡿㄪᰝ᪉ἲࡣ₯Ỉ࡛࠶ࡗࡓࠋࡲ
ࡓࠊᮏㄪᰝ࡛ࡣⅆཱྀ࠿ࡽࡢ㆙ᡄ⠊ᅖࡀ 1.5km ࠿ࡽ⦰ᑠࡏࡎࠊỈ῝ 0㹼30m ⛬ᗘࡢὸᾏᇦࡀ
Ꮡᅾࡍࡿ໭ഃᇦࡢࡳࡋ࠿ㄪᰝࡀ࡛ࡁ࡞࠿ࡗࡓࠋḟᅇࡢㄪᰝ࡛ࡣࠊすஅᓥ࿘ᅖࡢᾏὒ⏕≀┦ࢆᢕᥱࡍࡿࡓࡵ࡟ࠊ2019 ᖺࡢすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡛ⴭ⪅ࡢྥࡽ࡟ࡼࡾࢧࣥࢦ㢮ࡀほᐹࡉࢀ࡚࠸ࡿ㸦ᮍⓎ⾲㸧すഃࢆࡣࡌࡵࠊᮾഃࠊ༡ഃࡢᾏᇦࡶㄪᰝࡍࡿࡇ࡜ࡀᮃࡲࡋ࠸ࠋࢫࣝࢶ࢙
࢖ᓥ࿘㎶ᾏᇦࡢㄪᰝࡣࠊᄇⅆᚋ 5 ᖺ㛫ࡣ㐃⥆ࡋ࡚ࠊࡑࡢᚋࡣ 3 ᖺࡈ࡜࡟⾜ࢃࢀ࡚࠾ࡾ
㸦Sigurdsson, 2000㸧ࠊ㑄⛣ࡢ⤒㐣ࢆグ㘓ࡍࡿࡓࡵ࡟ࡣࠊ௒ᚋ 4 ᖺ⛬ᗘࡣẖᖺࠊࡑࡢᚋࡣ 3ᖺ⛬ᗘࡈ࡜࡟ㄪᰝࡍࡿࡇ࡜ࡀᮃࡲࡋ࠸ࠋ
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5. ㅰ㎡
 ᮏ◊✲ࡢᡂᯝࡣࠊ⎔ቃ┬ࡀ୺ദࡋ࡚ᐇ᪋ࡋࡓ௧࿴ 2 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟ࡼࡿࡶࡢ
࡛࠶ࡿࠋᾏὒ⏕≀┦ㄪᰝࢆ⾜࠺ୖ࡛ࡣࠊㄪᰝ㝲ࡢࢧ࣏࣮ࢺ࡜ࡋ࡚ࠊᾏὒ࢚ࣥࢪࢽ࢔ࣜࣥࢢ
ᰴᘧ఍♫ࡢ኱ཎ ṇᐶẶࠊ➨୕㛤ὒ୸ࡢἈᓮ ೺ḟ⯪㛗ࠊᚋ⸨ ὒྐ୍➼⯟ᾏኈ࡯࠿஌⤌ဨࡢⓙᵝ࡟ከ኱࡞ࡿ༠ຊࢆ࠸ࡓࡔ࠸ࡓࠋ㈅㢮ࡢྠᐃ࡟ࡣࠊᒸᒣ኱Ꮫࡢ⚟⏣ᏹ༤ኈࠊࡁࡋࢃࡔ⮬↛㈨ᩱ㤋ࡢ᯽ᑿ⩧Ặࡢ୧Ặ࡟ࡶࡈᑾຊ࠸ࡓࡔ࠸ࡓࠋࡲࡓࠊ᭷Ꮝ⹸ࡢྠᐃ࡟ࡣࠊᅜ❧◊✲㛤Ⓨἲேᾏὒ◊✲㛤Ⓨᶵᵓࡢᓊୖዉࠎ⨾Ặࠊᒾ㤋᭷ᕼẶ࡟ࡈ༠ຊ࠸ࡓࡔ࠸ࡓࠋࡇࡇ࡟῝࠸ឤㅰࡢពࢆ⏦ࡋୖࡆࡿࠋ࡞࠾ࠊᮏ◊✲ࡢ୍㒊ࡣ JSPS ⛉◊㈝ 21K05638㸦୕Ꮿ㸧ࡢຓᡂࢆཷࡅ࡚⾜ࢃࢀࡓࠋ
6. ᘬ⏝ᩥ⊩Barber PH, Moosa MK & Palumbi SR (2002) Rapid recovery of genetic diversity of stomatopod
populations on Krakatau: temporal and spatial scales of marine larval dispersal. Proceedings ofthe Royal Society of London 269: 1591-1597.

− 124 −

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Gunnarsson K & Hauksson E (2009) Succession and benthic community development in the
sublittoral zone at the recent volcanic island, Surtsey, southern Iceland. Surtsey Research 12:

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161-166.
ᾏୖಖᏳᗇ (2017) ἢᓊࡢᾏࡢᇶᮏᅗ➨ 6556 ྕ 8 すஅᓥ㸬ᾏୖಖᏳᗇ㸬⎔ቃ DNA Ꮫ఍ (2020) ⎔ቃ DNA ㄪᰝ࣭ᐇ㦂࣐ࢽࣗ࢔ࣝ Ver 2.2㸬https://ednasociety.org/wp-content/uploads/2022/06/eDNA_manual_ver2_2.pdf㸦᭱⤊㜀

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ぴ᪥㸸2023 ᖺ 1 ᭶ 20 ᪥㸧, 105p.
Miyake H, Oda A, Wada S, Kodaka T & Kurosawa S (2019) First record of a shallow hydrothermalvent crab, Xenograpsus testudinatus, from Shikine-jima Island in the Izu archipelago.

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Biogeography 21: 31-36.
᳃ ⱥ❶࣭

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ኵ࣭Ọ㔝 ⿱࣭ᑎ⏣ ๛࣭᪥㧘 ⿱⳹࣭Ᏻ㰻 ཭ᕭ࣭Ⳣ㔝 ᗣ♸࣭ᶓᒣ ┤ே㸦2020㸧➨ 1

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ᅇすஅᓥ⥲ྜᏛ⾡ㄪᰝࡢᴫ␎. ᑠ➟ཎ◊✲ 46: 1-35.
᳃ ⱥ❶࣭

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ᖺ࡟࠾ࡅࡿすஅᓥ⥲ྜᏛ⾡ㄪᰝࡢᴫ␎. ᑠ➟ཎ◊✲ 49: 1-43.
୰ᆓ ᚭḟ⦅㸦2013㸧ࠗ᪥ᮏ⏘ 㨶㢮᳨⣴ ඲✀ࡢྠᐃ ➨ 3 ∧࠘ᮾᾏ኱Ꮫฟ∧఍, 2428p.
㔝ཱྀ ౡせ࣭㛵᳃ ♸ᶞ࣭ᕳ ಇᏹ (2023) ⮬ᚊᆺᾏ୰ࣟ࣎ࢵࢺࢩࢫࢸ࣒࡟ࡼࡿすஅᓥᾏᗏㄪ
ᰝ. ᑠ➟ཎ◊✲ 49: 97-112
Oda A, Kayama Watanabe H, Ohtsuka S, Wada S, Kondo Y & Miyake H (2023) Does the Kuroshio
Current transport planktonic larvae of the hydrothermal-vent crab Xenograpsus Takeda &

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Kurata, 1977 (Decapoda: Brachyura: Grapsoidea)? Journal of Crustacean Biology 42: 1-8.
ᑠ➟ཎ⮬↛ᩥ໬◊✲ᡤ (2017) ᖹᡂ 28 ᖺᗘᑠ➟ཎㅖᓥᾏᇦ⏕ែㄪᰝጤクሗ࿌᭩. ᮾி㒔ᑠ➟ཎᨭᗇ, 506p.
ᒸᮧ ཰࣭ᑽᒸ 㑥ኵ㸦2007㸧ࠗ᪥ᮏࡢᾏỈ㨶࠘ᒣ࡜῱㇂♫, 783p.
Sigurdsson A (2000) A survey of the benthic coastal fauna of Surtsey in 1992 and a comparison withearlier data. Surtsey Research 11: 75-83.
Starger CJ, Barber PH, Ambariyanto & Baker AC (2010) The recovery of coral genetic diversity in
the Sunda Strait following the 1883 eruption of Krakatau. Coral Reefs 29: 547-565.
Takeda M & Kurata Y (1977) Crabs of the Ogasawara Islands. IV. A collection made at the new
volcanic island, Nishino-shima-shinto, in 1975. Bulletin of the National Science Museum, Tokyo,

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㝯୍࣭ᑠᒣ⏣ భ㍜࣭ᕝୖ ࿴ே࣭ྥ ဴႹ࣭ᕝཱྀ ኱ᮁ࣭㧗ᕊ ᫓ኵ࣭㇏⏣㸦ᑠ㇂㔝㸧 ᭷ຍ࣭ᮧୖ ຬᶞ࣭Ọ㔝 ⿱࣭᪥㧘 ⿱⳹࣭Ᏻ㰺 ཭ᕭ࣭Ᏺ ᐜᖹ㸦2023㸧2021

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㝯୍࣭ᑠᒣ⏣ భ㍜࣭ᕝୖ ࿴ே࣭኱‖ 㝯㞝࣭ྥ ဴႹ࣭ᕝཱྀ ኱ᮁ࣭㧗ᕊ ᫓Ser. A (Zoology) 3: 91-111.
ᒣᓮ ༤ྐ࣭⸨ᮏ ᚰኴ࣭⏣୰ 㞙ே㸦2019㸧ᾏ⏘࣓࢖࢜࣋ࣥࢺࢫ㸦ᑠᆺᗏ⏕⏕≀ࡢ᥇㞟࠾ࡼࡧᢳฟ᪉ἲ. ࢱࢡࢧ ᪥ᮏື≀ศ㢮Ꮫ఍ㄅ 46㸸40-53㸬

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− 125 −

ᅗ 1ㄪᰝᆅⅬa㸬Ỉ㉁ㄪᰝᆅⅬ b㸬᥇ỈᆅⅬ c㸬ᗏ⏕⏕≀᥇㞟ᆅⅬ d㸬ࣉࣛࣥࢡࢺࣥ᥇㞟ᆅⅬ e㸬⁻ὶ≀᥇ྲྀᆅⅬࠋ Ỉ㉁ㄪᰝᆅⅬࠊ ᥇ỈᆅⅬࠊ㸩᥇ἾᆅⅬࠊࠐ₯ỈㄪᰝᆅⅬࠊ‫ڧ‬ኪ⾜ᛶࡢ⏕≀᥇㞟ᆅⅬࠊ‫ࣥࢺࢡࣥࣛࣉڹ‬᥇㞟ᆅⅬࠊ‫ە‬⁻ὶ≀᥇ྲྀᆅⅬࠋa~e㸬ᮏㄪᰝ࡛➨୕ᾏὒ୸ࡼࡾྲྀᚓࡉࢀࡓᾏᗏᆅᙧᅗ㸦ཧ⪃ࢹ࣮ࢱ㸧ࢆᨵኚࠋⓑࡃᢤࡅ࡚࠸ࡿ㒊ศࡣࢹ࣮ࢱࢆྲྀᚓࡋ࡚࠸࡞࠸ࠋd㸬ᾏୖಖᏳᗇ㸦2017㸧࡟ᮏㄪᰝ࡛ྲྀᚓࡉࢀࡓᾏᗏᆅᙧᅗ㸦ཧ⪃ࢹ࣮ࢱ㸧ࢆ㏣グࠋ− 126 −

Figure 1. Survey locations around Nishinoshimaa. Water quality survey sites, b. Water sampling sites, c. Benthos sampling sites, d. Plankton
sampling sites, e. Drifting object sampling sites. Survey location: Water quality survey sites,
Water sampling sites, 㸩Mud sampling sites, ࠐScuba diving survey sites, ‫ڧ‬Sampling of
nocturnal animals sites, ‫ڹ‬Plankton sampling sites, ‫ە‬Drifting object sampling sites. a~d. The
maps modified from bathymetric chart from No.3 KAIYO MARU. White space describes nodata. d. The map modified from bathymetric chart from No.3 KAIYO MARU and Japan

Coast Guard (2017).

ᅗ 2₯ỈㄪᰝᆅⅬࡢᾏᗏ㸦᧜ᙳ㸸a㸬c㸬ᗈ℩ࠊb㸬d㸬㇏⏣㸧a㸬 St. S1ࠋb㸬St. S2ࠋc㸬St. S3ࠋd㸬St. S4ࠋ

Figure 2. Landscapes at the scuba diving survey locations

a. St.S1. b. St.2. c. St.3. d. St.4. (Photos a and c by M. Hirose, and b and d by Y. Toyota)

− 127 −

ᅗ 3. ₯ỈㄪᰝࡢᵝᏊa㸬ᗏ⏕⏕≀ࡢ᥇ྲྀࠋb㸬᪉ᙧᯟෆࡢᗏ㉁ࡢ᥇ྲྀࠋ
㸦᧜ᙳ㸸a㸬ྥࠊb㸬㇏⏣㸧Figure 3. Scuba diving survey

a. Benthos sampling. b. Mud sampling in a quadrat.㸦Photos a by A. Mukai and b by Y. Toyota)

ᅗ 4ࣛ࢖ࢺࢺࣛࢵࣉ㸦᧜ᙳ㸸ྥ㸧

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

Figure 4. Plankton trap with lights. (Photo by A. Mukai)− 128 −

ᅗ 5. すஅᓥ࿘㎶ࡢᾏᗏᆅᙧࡢኚ໬
a㸬 2017 ᖺࠋẚ㍑ࡢࡓࡵ 2021 ᖺࡢㄪᰝᆅⅬࢆ⾲♧ࠋb㸬2021 ᖺࠋ㸩᥇ἾᆅⅬࠊࠐ₯ỈㄪᰝᆅⅬࠊ‫ڧ‬ኪ⾜ᛶࡢ⏕≀᥇㞟ᆅⅬࠋa㸬ᾏୖಖᏳᗇ㸦2017㸧࡟㏣グࠋb㸬ᮏㄪᰝ࡛➨୕㛤ὒ୸ࡼࡾྲྀᚓࡉࢀࡓᾏᗏᆅᙧᅗ㸦2021 ᖺ㸧ࠋⓑࡃᢤࡅ࡚࠸ࡿ㒊ศࡣࢹ࣮ࢱࢆྲྀᚓࡋ࡚࠸࡞࠸ࠋ
Figure 5. Bathymetric change around Nishinoshima Islanda. in 2019. Survey locations in 2021 described for comparison. b. in 2021. Survey location:㸩Mudsampling, ࠐScuba diving sampling, ‫ڧ‬Sampling of nocturnal animals. a. The map modified
from Japan Coast Guard (2017). b. The map modified from bathymetric chart from No.3 KAIYO
MARU. White space describes no data.

− 129 −

ᅗ 6すஅᓥすഃࡢᾏỈࡢኚⰍᇦ㸦᧜ᙳ㸸ᗈ℩
Figure 6. Discoloration of water around the southern area of Nishinoshima Island (Photo by M.

Hirose)

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− 130 −

ᅗ 7-1すஅᓥ࿘㎶ᾏᇦࡢỈ㉁ࠋa㸬St. N Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧
ࠋb㸬St. N ࢡࣟࣟࣇ࢕ࣝ a㸦μg /L㸧ࠊ⃮ᗘ㸦FTU㸧௨ୗྠᵝࠋc㸬d㸬St. NE ࠋe㸬f㸬St. Eࠋ
Figure 7-1. Sea water quality around Nishinoshima Islanda. St. N Water temperature (℃), Salinity, DO (mg/L). b. St. N Chlorophyll-a (μg /L), Turbidity(Formazin Turbidity Unit). The same shall apply hereafter. c. d. St. NE., e. f. St. E.

− 131 −

ᅗ 7-2すஅᓥ࿘㎶ᾏᇦࡢỈ㉁ࠋg㸬St. SE Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧
ࠋh㸬St. SE ࢡࣟࣟࣇ࢕ࣝ a㸦μg /L㸧ࠊ⃮ᗘ㸦FTU㸧௨ୗྠᵝࠋi㸬j㸬St. S ࠋk㸬l㸬St. SWࠋ
Figure 7-2. Sea water quality around Nishinoshima Islandg. St. SE Water temperature (℃), Salinity, DO (mg/L). h. St. SE Chlorophyll-a (μg /L), Turbidity(FTU). The same shall apply hereafter. i. j. St. S., k. l. St. SW.

− 132 −

ᅗ 7-3. すஅᓥ࿘㎶ᾏᇦࡢỈ㉁ࠋm㸬St. W Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧
ࠋn㸬St. W ࢡࣟࣟࣇ࢕ࣝ a㸦μg /L㸧ࠊ⃮ᗘ㸦FTU㸧௨ୗྠᵝࠋo㸬p㸬St. NWࠋ
Figure 7-3. Sea water quality around Nishinoshima Islandm. St. W Water temperature (℃), Salinity, DO (mg/L). n. St. W Chlorophyll-a (μg /L), Turbidity

(FTU). The same shall apply hereafter. o. p. St. NW.

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
− 133 −

ᅗ 8-1すஅᓥ࿘ᅖࡢỈ㉁㸦➼್⥺ᅗ㸧ࠋa㸬Ỉ 㸦℃㸧ࠋb㸬Ỉ῝ 20m ௨ὸࡢỈ 㸦℃㸧

Figure 8-1. Water quality around Nishinoshima Island (Contour figure)a. Water temperature (Υ). b. Water temperature over 20m depth (Υ).

− 134 −

ᅗ 8-2すஅᓥ࿘㎶ᾏᇦࡢỈ㉁㸦➼್⥺ᅗ㸧c㸬ሷศࠋd㸬Ỉ῝ 20m ௨ὸࡢ⃮ᗘ㸦FTU㸧
ࠋFigure 8-2. Water quality around Nishinosnima Island (Contour figure)c. Salinity. d. Turbidity over 20m depth (FTU).




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
− 135 −

ᅗ 8-3. すஅᓥ࿘㎶ᾏᇦࡢỈ㉁㸦➼್⥺ᅗ㸧ࠋe㸬DO㸦mg/L㸧ࠋf㸬Ỉ῝ 20m ௨ὸࡢ DO㸦mg/L㸧

Figure 8-3. Water quality around Nishinoshima Island(Contour figure)e. DO (mg/L). f. DO over 20m depth (mg/L).

− 136 −

ᅗ 8-4. すஅᓥ࿘㎶ᾏᇦࡢỈ㉁㸦➼್⥺ᅗ㸧ࠋg㸬ࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧ࠋh㸬Ỉ῝ 20m ௨ὸࡢࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧

Figure 8-4. Water quality around Nishinoshima Island (Contour figure)g. Chlorophyll-a (μg/L). h. Chlorophyll-a over 20m depth (μg/L).

− 137 −

ᅗ 9-1᥇ἾᆅⅬ࠾ࡼࡧ᥇ỈᆅⅬࡢỈ㉁a㸬St. 1 Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L)ࠋb. St. 1 ࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧ࠊ⃮ᗘ㸦FTU)ࠋ௨
ୗྠᵝࠋc㸬d㸬St. 2ࠋe㸬f㸬St. 3ࠋ
Figure 9-1. Water quality at mud sampling and water sampling locations
a. St. 1 Water temperature (℃), Salinity, DO (mg/L). b. St. W Chlorophyll-a (μg /L), Turbidity(FTU). The same shall apply hereafter. c. d. St. 2., e. f. St.3.

− 138 −

ᅗ 9-2᥇ἾᆅⅬ࠾ࡼࡧ᥇ỈᆅⅬࡢỈ㉁g㸬St. 4 Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧
ࠋh㸬St. 4 ࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧ࠊ⃮ᗘ㸦FTU㸧ࠋ௨ୗྠᵝࠋi㸬j㸬St. 5ࠋ
Figure 9-2. Water quality at mud sampling and water sampling locations
g. St. 4 Water temperature (℃), Salinity, DO (mg/L). h. St. 4 Chlorophyll-a (μg /L), Turbidity (FTU).

The same shall apply hereafter. i. j. St. 5.




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


− 139 −

ᅗ 10₯Ỉㄪᰝ୰㸦a- e㸧ࡲࡓࡣ₯ỈㄪᰝᆅⅬ㸦f ࡢỈ㉁a㸬St. S1 Ỉ 㸦℃㸧ࠊሷศࠋb㸬St. S2 Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧
ࠋc㸬St. S2 ࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧ࠊ⃮ᗘ㸦FTU)ࠋd㸬St. S3 Ỉ 㸦℃㸧
ࠊሷศࠊDO㸦mg/L㸧ࠋe㸬St. S3 ࢡࣟࣟࣇ࢕ࣝ a㸦μg/L㸧ࠊ⃮ᗘ㸦FTU㸧
ࠋf㸬St. S4 Ỉ 㸦℃㸧ࠊሷศࠋ a㸬f㸬ࡢࡳ
CTD ࡛ ᐃࠋ௚ࡣ࣓࣮ࣔࣜCTD ࡛ ᐃࠋ
− 140 −

Figure 10. Water quality during scuba diving (a- e) and at scuba diving survey location (f).
a. St. S1 Water temperature (℃), Salinity. b. St. S2 Water temperature (℃), Salinity , DO (mg/L). c.
St. 2 Chlorophyll-a (μg /L), Turbidity (FTU). d. St. S3 Water temperature (℃), Salinity, DO (mg/L).
e. St. S3 Chlorophyll-a (μg /L), Turbidity (FTU). f. St. S4 Water temperature (℃). a. f. measured by

CTD and other by memory CTD.

ᅗ 11すஅᓥࡢ₻㛫ᖏ࡛☜ㄆࡉࢀࡓ⏕≀࢔࢟ࢿࢺࢫࢺ࣏ࣛ⛉ࡢ୍✀ࠋ㸦᧜ᙳ㸸ᑎ⏣㸧
Figure 11. Seaweed recorded in the intertidal zone of Nishinoshima Island

Acinetosporaceae sp. (Photo by R.Terada)− 141 −


図 12-1西之島周辺海域で確認された底生生物
a．シロガヤ属の一種。b．ミナミアカフジツボ。c．ハグチコケムシ科の一種。d．クダコ
ケムシ科の一種。e．アミコケムシ科、カゲロウガイ。 f．ツノヒラムシ近似種。g．フサ（撮影：a．b．e．
ゴカイ亜科の一種。h．サシバゴカイ科の一種。 i．シロガヤ属の一種。

豊田、c~d、f~i．広瀬）Figure 12-1. Benthos recorded around Nishinoshima Islanda. Aglaophenia sp. b. Megabalanus occator c. Tubuliporidae. d. Tubuliporidae. e.Phidoloporidae,
Streptopinna saccata. f. Planocera cf. reticulataf. g.Terebellinae. h. Phyllodocidae. i. Aglaophenia

sp. (Photos a, b and e by Y. Toyota and c-d and f~i by M. Hirose)

− 142 −

ᅗ 12-2. すஅᓥ࿘㎶ᾏᇦ࡛☜ㄆࡉࢀࡓᗏ⏕⏕≀j㸬ࣁࢿ࢞ࣖᒓࡢ୍✀ࠋk㸬Triticella spࠋl. Euechinoidea ள⥘ࡢ୍✀ࠋm㸬ࣄࣀࢹࢽࢩ࢟ࠋn㸬 ࣅ࣡࢞ࢱࢼ࣓ࢡࢪࠋo㸬࢖࣑࣎࢘ࢢࣔ⛉ࡢ୍✀ࠋp㸬࢔࢚࢝ࣅᒓࡢ୍✀ࠋ q㸬ࣚࢶࣁ࢖ࢩ࢞ࢽࠋ r㸬ࣄ࣓࣋ࢽࢶࢣ࢞ࢽࠋ
㸦᧜ᙳ㸸j~ q㸬ᗈ℩ࠊr㸬ᑠᯇ㸧Figure 12-2. Benthos recorded around Nishinoshima Islandj. Plumlaria sp. k. Triticella sp. l. Euechinoidea. m. Laevichlamys boninensis. n. Dolabrifera
dolabrifera. o. Rhynchothoracidae. p. Metapenaeopsis sp. q. Gonioinfradens paucidentatus. r.

Thalamita picta. (Photos j~q by M. Hirose and r by H. Komatsu)





− 143 −

ᅗ 13ᾏᗏ࡟タ⨨ࡋࡓ᪉ᙧᯟ࡜ᗏ㉁ࡢᵝᏊ
a㸬St.S1ࠋ26.7mࠋᯟࢧ࢖ࢬ 1m×1mࠋb㸬St.S1ࠋ26.7mࠋᯟࢧ࢖ࢬ 50cm×50cmࠋ
c㸬St.S1ࠋ13.6mࠋᯟࢧ࢖ࢬ 1m×1mࠋd㸬St.S1ࠋ13.6mࠋᯟࢧ࢖ࢬ 50cm×50cmࠋ
e㸬St.S4ࠋ29.8mࠋᯟࢧ࢖ࢬ 1m×1mࠋf㸬St.S4ࠋ29.8mࠋᯟࢧ࢖ࢬ 50cm×50cmࠋ
g㸬St.S4ࠋ18.7mࠋᯟࢧ࢖ࢬ 1m×1mࠋh㸬St.S4ࠋ18.7mࠋᯟࢧ࢖ࢬ 50cm×50cmࠋ
㸦᧜ᙳ㸸ᗈ℩㸧
Figure 13. Quadrats on the sea floor and sedimentsa㸬St.S1. 26.7m. Quadrat size: 1m×1m. b㸬St.S1. 26.7m. Quadrat size: 50cm×50cm.
c㸬St.S1. 13.6m. Quadrat size: 1m×1m. d㸬St.S1. 13.6m. Quadrat size: 50cm×50cm.
e㸬St.S4. 29.8m. Quadrat size: 1m×1m. f㸬St.S4. 29.8m. Quadrat size: 50cm×50cm.
g㸬St.S4. 18.7m. Quadrat size: 1m×1m. h㸬St.S4. 18.7m. Quadrat size: 50cm×50cm. (Photos by M.

Hirose)





− 144 −

ᅗ 14すஅᓥ࿘㎶ᾏᇦ࡛ᗏ㉁୰࡟☜ㄆࡉࢀࡓ࣓࢖࢜࣋ࣥࢺࢫ
a㸬Rosalina globularisࠋb㸬ࢧࢩࣂࢦ࢝࢖⛉ࡢ୍✀ࠋPhyllodocidaeࠋc㸬ࣀࣛࣜ࢘ࣟࢥ࣒ࢩ⛉ࡢ୍✀ࠋ㸦᧜ᙳ㸸a㸬㇏⚟ࠊ㛗஭ࠊb㸬ᗈ℩㸧Figure 14. Meiobenthos recorded in sea floor sediments around Nishinoshima Island
Rosalina globularis. b. Phyllodocidae. c. Pisione sp. (Photos a by T. Toyofuku & Y. Nagai and b by

M. Hirose)− 145 −

ᅗ 15すஅᓥ࿘㎶ᾏᇦ࡛☜ㄆࡉࢀࡓᗏ⏕⏕≀ࡢᗂ⏕a㸬஧ᯛ㈅⥘ࠋb~g㸬༑⬮┠ࠋ㸦᧜ᙳ㸸୕Ꮿ㸧
Figure 15. Benthos larvae recorded around Nishinoshima Island

a. Bivalvia. b~g. Decapoda. (Photos by H. Miyake)− 146 −

ᅗ 16すஅᓥ࿘㎶ᾏᇦ࡛☜ㄆࡉࢀࡓ୺࡞㨶㢮a㸬࢞ࣛࣃࢦࢫࢨ࣓ࠋb㸬࢔࢝ࣁࢱࠋ c㸬࢝ࢵ࣏ࣞࠋd㸬ࣚࢫࢪࣇ࢚ࢲ࢖ࠋ e㸬ࣘ࢘ࢮࣥࠋf㸬ࢶࣂ࣓࢘࢜ࠋ g㸬࢖ࢯ࣐ࢢࣟࠋh㸬࣑ࢰࣞࣇࢢࠋ i㸬ࢺࣅࢠ࣏ࣥࠋ
㸦᧜ᙳ㸸a㸬d㸬e㸬i㸬ᗈ℩ࠊb㸬୕Ꮿࠊc㸬g㸬㇏⏣ࠊf㸬h㸬࢔࢖ࣛࣥࢬࢣ࢔㸧
Figure 16. Fish observed around Nishinoshima Islanda. Carcharhinus galapagensis. b. Epinephelus fasciatus. c. Caranx lugubris. d. Lutjanus kasmira. e.
Chaetodon daedalma. f. Platax teira. g. Gymnosarda unicolor. h. Arothron meleagris. i. Limnichthysfasciatus. (Photos a, d, e and i by M. Hirose, b by H. Miyake, c and g by Y. Toyota and f and h byIslands Care)− 147 −

ᅗ 17すஅᓥ࿘㎶ᾏᇦ࡛᥇㞟ࡉࢀࡓ⁻ὶ≀a㸬ࢥ࣮ࣄ࣮ࡢᐜჾ࡟஌ࡿࢶࣈ࢖࣎ࢩࣙ࢘ࢪࣥ࢞ࢽࠋb㸬㛗㠐ࠋୗ࡟ࡣ࢔࣑ࣔࣥ࢞ࣛࡀ㞃ࢀ࡚࠸ࡿࠋc㸬ࢥ࢞ࢱ࣑࢘࢔࣓ࣥ࣎ࠋ d㸬ࣖࣂࢿࣔࢡࠋe㸬ࢳࢠࣞ࢖ࢯࢠࣥࢳࣕࢡ㏆ఝ✀ࠊ㸦᧜ᙳ㸸a㸬 ࠊb㸬f㸬㇏ࢧ࣓ࣁࢲࢥࢣ࣒ࢩᒓࡢ୍✀ࠋf㸬࢔࣑ࣔࣥ࢞ࣛࠊ࢜࢟ࢼ࢞ࣞ࢞ࢽࠋ

⏣ࠊc㸬᳃ࠊ d㸬e㸬ᗈ℩㸧Figure 17. Drifting objects observed around Nishinoshima Islanda. Plagusia immaculata on the coffee container. b. Canthidermis maculate in the rain boot.
c. Halobates sericeus. d. Hormophysa cuneiformis.

e. Exaiptasia cf. pallida (=Exaiptasia

diaphana), Jellyella cf. eburnea. f. Canthidermis maculata, Planes major. (Photos a by R. Minato, band f by Y. Toyota, c by H. Mori, and d and e by M. Hirose)












− 148 −

⾲ 1ㄪᰝ⾜⛬Table1. Schedule of marine survey
ㄪᰝ᪥

ㄪᰝᆅⅬྡ

ㄪᰝෆᐜ

ᡭ⥙

⏕≀ほᐹ࠾ࡼࡧ᥇㞟27.25817

140.88308

2021/7/7 ໭ഃࡢ☾ᡭ⥙⏕≀ほᐹ࠾ࡼࡧ᥇㞟27.25818

140.88308―

2021/7/9 ⁻ὶ≀_࣮ࣟࣉ⁻ὶ≀ᅇ཰

27.1477140.51695―

Ỉ㉁ ᐃ

27.26392

140.87642

17.0

2021/7/9 St.E1-1

ࡓࡶ⥙࣓ࣔࣜ―CTD,㏱᫂ᗘᯈ
࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ1, 227.26392

140.87642

17.0

2021/7/9 St.E1-2

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ3

27.26392

140.87642

17.0

2021/7/9 St.E1-3

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ4, 5, 6

27.26392

140.87642

17.0

2021/7/9 St.2

㏱᫂ᗘᯈ

Ỉ㉁ ᐃ

27.26134140.88499

31.8

2021/7/9 St.2

࣓ࣔࣜ―CTDỈ㉁ ᐃ

27.26104140.88569

130.0

2021/7/9 St.1

⤒ᗘ―2021/7/9 St.2

ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ3ᅇ

27.26104140.88569

10.0

2021/7/9 St.E2-1

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ1

27.2614140.88468

105.0

2021/7/9 St.E2-2࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ2

27.26135

140.8845

107.0

2021/7/9 St.E2-3

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ3

27.26137

140.88465

103.0

2021/7/9 St.3

࣓࣮ࣔࣜCTDỈ㉁ ᐃ

27.26106140.88473

94.0

2021/7/9 St.3

᥇Ỉ2ᅇ

27.26106140.88473

10.0ࣉࣛࣥࢡࢺࣥ᥇㞟

27.26106140.88449

94.0

2021/7/9 St.4

ࣂࣥࢻ࣮ࣥ᥇Ỉჾࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦㖄┤᭥ࡁ㸧࣓࣮ࣔࣜCTDỈ㉁ ᐃ

27.26065

140.88412

60.0

2021/7/9 St.4

㏱᫂ᗘᯈ

Ỉ㉁ ᐃ

27.26059

140.88434

39.0

2021/7/9 St.3

2021/7/9 St.E4-1

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ1

27.26068

140.88452

62.8

2021/7/9 St.E4-2

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ2

27.2606

140.88437

56.5
64.9

2021/7/9 St.E4-3

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ3

27.26047

140.88472

2021/7/9 St.E4-4

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ4

27.26063

140.88438

64.8

2021/7/9 St.E4-5

࢚ࢡ࣐ࣥࣂ࣮ࢪ

᥇Ἶ5

27.26068

140.88435

64.9

2021/7/9 St.5

Ỉ㉁ ᐃ

27.26034

140.88412

45.4

ࣉࣛࣥࢡࢺࣥ᥇㞟

27.26009

140.88419

42.8

2021/7/9 St.6

࣓࣮ࣔࣜCTDࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦㖄┤᭥ࡁ㸧
ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ127.2583

140.88362

10.0

2021/7/9 St.6

ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ227.25822

140.88373

10.0

2021/7/9 St.6

ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ327.25844

140.8836ࡶࢇ࡝ࡾኪ⾜ᛶࡢ⏕≀᥇㞟1
㸦2ಶ㸧

27.25818

140.8831

2021/7/9 St.5

2021/7/9

St.A㸦࢔࣮࣏ࣥ࢝
࢖ࣥࢺ㸧➨୕㛤ὒ୸࡟ࡼࡾྲྀᚓࡉࢀࡓỈ῝
Depth obtained from No.3 KAIYO MARU












⦋ᗘ

Ỉ῝ m

ㄪᰝ᪉ἲ

2021/7/7 ໭ഃࡢ☾− 149 −

10.0
Ἀഃ20- 25,㝣ഃ15- 20 ⾲ 1⥆ࡁ
Table1. Continued
ㄪᰝ᪥

ㄪᰝᆅⅬྡ

ㄪᰝෆᐜ

2021/7/10 St.S1₯Ỉ⏕≀ほᐹ࠾ࡼࡧ᥇㞟

2021/7/10 St.S1

CTD

Ỉ㉁ ᐃ

27.258140.88358

0- 27.3
㸦ᖹᆒ15.6㸧
0-20.852021/7/10 St.S2

CTD

Ỉ㉁ ᐃ㸦₯Ỉ୰㸧

27.25844

140.87978

0-19.62021/7/10 St.S2₯Ỉ⏕≀ほᐹ࠾ࡼࡧ᥇㞟27.25844

140.87978

2021/7/10 St.7

࣓࣮ࣔࣜCTDỈ㉁ ᐃ

27.25837

140.87984

0- 21
㸦ᖹᆒ14.9㸧
21.7

2021/7/10 St.7

ࣉࣛࣥࢡࢺࣥ᥇㞟27.25832

140.87987

21.3

2021/7/10 St.7

ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦㖄┤᭥ࡁ㸧
ࣂࣥࢻ࣮ࣥ᥇Ỉჾ

2021/7/10 St.7

ࣂࣥࢻ࣮ࣥ᥇Ỉჾ

27.25843

140.87985

10.0

140.87987

10.0ࣂࣥࢻ࣮ࣥ᥇Ỉჾࡶࢇ࡝ࡾ,ࣛ࢖ࢺࢺࣛࢵࣉ
ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
2021/7/10 St. P ᮾഃ᪥ἐ᫬
㸦20m×2ᅇᩳࡵᘬࡁ㸧ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
2021/7/10 St. Pᮾഃ᪥ἐ1hᚋ㸦20m×2ᅇᩳࡵᘬࡁ㸧᥇Ỉ327.25845

140.87988

10.0ኪ⾜ᛶࡢ⏕≀᥇㞟2
㸦2ಶ㸧

27.25848

140.88113

Ἀഃ20- 25,㝣ഃ15- 20ࣉࣛࣥࢡࢺࣥ᥇㞟

27.247994

140.900345―

ࣉࣛࣥࢡࢺࣥ᥇㞟

27.247994

140.900345―

2021/7/11 St.S3

₯Ỉ

Ỉ㉁ ᐃ

27.25638

140.88719

St.A㸦࢔࣮࣏ࣥ࢝
࢖ࣥࢺ㸧

2021/7/11 St.S3

CTD

Ỉ㉁ ᐃ㸦₯Ỉ୰㸧

27.25638

140.88719

0- 12.6
㸦ᖹᆒ12.6㸧
0-11.522021/7/11 St.8

࣓࣮ࣔࣜCTDỈ㉁ ᐃ

27.25676

140.88675

12.9

2021/7/11 St.8ࣉࣛࣥࢡࢺࣥ᥇㞟27.25671

140.88675

12.6

2021/7/11 St.8ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦㖄┤᭥ࡁ㸧
ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ127.25668

140.88671

10.0

2021/7/11 St.8ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉ227.25668

140.8867

10.0

2021/7/11 St.8ࣂࣥࢻ࣮ࣥ᥇Ỉჾ

27.25663

140.88671

10.0

2021/7/11 St.8

ࡶࢇ࡝ࡾ

᥇Ỉ3
ኪ⾜ᛶࡢ⏕≀᥇㞟3
㸦1ಶ㸧ࡶࢇ࡝ࡾᘏ⦖
㸦5ಶ㸧

27.25663

140.88671

27.25856

140.88005⁻ὶ≀ᅇ཰27.25896

140.87938

ࡶࢇ࡝ࡾᘏ⦖
ࡓࡶ⥙

2021/7/11 ⁻ὶ≀_ࡦࡶ௚

ࡓࡶ⥙
⁻ὶ≀ᅇ཰
ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
2021/7/11 St. P すഃ᪥ἐ᫬ࣉࣛࣥࢡࢺࣥ᥇㞟㸦20m×2ᅇᩳࡵᘬࡁ㸧ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
2021/7/11 St. Pすഃ᪥ἐ1hᚋࣉࣛࣥࢡࢺࣥ᥇㞟㸦20m×2ᅇᩳࡵᘬࡁ㸧➨୕㛤ὒ୸࡟ࡼࡾྲྀᚓࡉࢀࡓỈ῝







Depth obtained from No.3 KAIYO MARU 












140.88358

27.25829

St.A㸦࢔࣮࣏ࣥ࢝
2021/7/11
࢖ࣥࢺ㸧
2021/7/11 ⁻ὶ≀_㛗㠐

27.258᥇Ỉ12021/7/10 St.7



⤒ᗘ

᥇Ỉ2

2021/7/10



⦋ᗘ

Ỉ῝ m

ㄪᰝ᪉ἲ

− 150 −

12.6
Ἀഃ20- 25,㝣ഃ15- 20―

27.25649

140.88714―

27.251056

140.834719―

27.251056

140.834719―

⾲ 1⥆ࡁ
Table1. Continued
ㄪᰝ᪥

ㄪᰝᆅⅬྡ

ㄪᰝෆᐜ

CTD

Ỉ㉁ ᐃ

27.25629

140.88779

2021/7/12 St.S4₯Ỉ⏕≀ほᐹ࠾ࡼࡧ᥇㞟27.25629

140.88779

2021/7/12 ⁻ὶ≀_Წ

ࡓࡶ⥙

⁻ὶ≀ᅇ཰

27.25697

140.88687

0- 30.6㸦ᖹᆒ18.3㸧
―2021/7/12 ⁻ὶ≀_࢝ࢦ

ࡓࡶ⥙

⁻ὶ≀ᅇ཰

27.25929

140.87722

―

ࡓࡶ⥙

⁻ὶ≀ᅇ཰

27.25969

140.88087―

27.210505

140.886434―

27.210506

140.886434―

27.2695

140.86535

10.6

27.2695

140.86535

25.0

2021/7/12⁻ὶ≀_ࢥ࣮ࣄ࣮
ࡢᐜჾ

2021/7/12 St. P༡ഃ᪥ἐ᫬
2021/7/12 St. P༡᪥ἐ1hᚋ2021/7/13 St.PN
2021/7/13 St.N
2021/7/13 St.PNE
2021/7/13 St.NE

ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
ࣉࣛࣥࢡࢺࣥ᥇㞟㸦20m×2ᅇᩳࡵᘬࡁ㸧ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
ࣉࣛࣥࢡࢺࣥ᥇㞟㸦20m×2ᅇᩳࡵᘬࡁ㸧ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
ࣉࣛࣥࢡࢺࣥ᥇㞟,㸦20m×2ᅇᩳࡵᘬࡁ㸧,
CTD
CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃ

2021/7/13 St.W

ࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓࣮ࣔࣜCTDỈ㉁ ᐃࣉࣛࣥࢡࢺࣥ᥇㞟,ࣉࣛࣥࢡࢺࣥࢿࢵࢺ
㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD
࣓ࣔࣜ―CTDỈ㉁ ᐃ

2021/7/13 St.NW㸦ኚⰍᇦ㸧࣓࣮ࣔࣜCTD

2021/7/13 St.PE
2021/7/13 St.E
2021/7/13 St.PSE
2021/7/13 St.SE
2021/7/13 St.PS
2021/7/13 St.S
2021/7/13 St.PSW
2021/7/13 St.SW
2021/7/13 St.PW

Ỉ㉁ ᐃ

2021/7/13 St.NW㸦ኚⰍᇦ㸧ࣂࣥࢻ࣮ࣥ᥇Ỉჾ᥇Ỉࣉࣛࣥࢡࢺࣥࢿࢵࢺ
ࣉࣛࣥࢡࢺࣥ᥇㞟,
2021/7/13 St.PNW㸦ኚⰍᇦ㸧㸦20m×2ᅇᩳࡵᘬࡁ㸧 CTD➨୕㛤ὒ୸࡟ࡼࡾྲྀᚓࡉࢀࡓỈ῝










Depth obtained from No.3 KAIYO MARU












− 151 −

⦋ᗘ

⤒ᗘ

Ỉ῝ m

ㄪᰝ᪉ἲ

2021/7/12 St.S4

0-43.69

27.25801

140.87538

11.6

27.25397

140.88958

60.0

27.25396

140.88974

11.6

27.2444140.89433

220.0

27.24462

140.89436

12.7

27.22434

140.88673

177㹼18627.22906

140.87953

14.7

27.22896

140.87941

303㹼330

27.22888

140.87935

13.4

27.23324

140.86909

284.0

27.23353

140.86928

14.6

27.24264140.86326

250㹼19027.2513140.8624

215.0

27.25131

140.86239

5.0

27.25282

140.86036

13.1



⾲ 22021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ ඲✀Table2. All species recorded during the Nishinoshima comprehensive scientific research project in2021㛛ศ㢮䠄㏻⛠䠅

࣋ࣥࢺࢫ

₻㛫ᖏ

࣐ࢡࣟ
࣋ࣥࢺࢫ
⣚Ⰽ࣭⥳Ⰽ࣭
㯤Ⰽ᳜≀㛛

⸴㢮

᭷Ꮝ⹸㛛

᭷Ꮝ⹸

่⬊ື≀㛛

₻ୗᖏ
ࣉࣛࣥࢡ
ࢺࣥ

࣓࢖࢜
࣋ࣥࢺࢫ

ື≀ࣉࣛ
ࣥࢡࢺࣥ

11

⥺ᙧື≀㛛

⥺⹸

㌾యື≀㛛

㈅㢮㸦࣑࢘࢘ࢩྵࡴ㸧

⎔ᙧື≀㛛

ከẟ

8

3
1

1

1

1
2

1

࣍ࢩ࣒ࢩ

1
3

࢝࢖࢔ࢩ

1

࢚࣎ࢩ࢞࢖࣭ࣇࢪࢶ࣎

2

11

5

31

19

4

34

1

3

1

22

3
20

1

3

1

1

9

2

16

9

3

26

2

18

➼⬮
1

➃⬮
࢚ࣅ࣭࢝ࢽ㸦᧜ᙳࡢࡳࡶྵࡴ㸧
࣒ࣖࢩ

Ჲ⓶ື≀㛛

࢘ࢽ

⬨⣴ື≀㛛

࣑࢘ࢱࣝ➼

⬨᳝ື≀㛛

㨶㸦᧜ᙳࡢࡳࡶྵࡴ㸧

1

4

13
14

2
4

2

4

2

4
4

1
3

ィ

64

2
2

14

࣑࢘ࢢࣔ

1
14

1

ࣄ࣒ࣛࢩ

ẟ㢡ື≀㛛

3
1

3

ࢡࢩࢡࣛࢤ

ࢥࢣ࣒ࢩ

2

1

ࣄࢻࣟ⹸

ⱏ⹸ື≀㛛

☜ㄆ✀
ྜィ

1

࢖ࢯࢠࣥࢳࣕࢡ

ᡥᙧື≀㛛

⠇㊊ື≀㛛

⁻ὶ

㨶㢮

1

᭷᷸ື≀㛛

ཱྀᫍື≀㛛

ࢿࢡࢺࣥ

6
15

94

4
49

ˠ

4

60

49

28

253



※1 ෗┿࡛ࡢ☜ㄆࡢࡳࠋ

※1 A species observed by photos.


⾲ 3-12021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀⸴㢮
Table3-1. Fucistia recorded during the Nishinoshima comprehensive scientific research project in2021⥘┠ ⛉ Ꮫྡ

໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡPhaeophyceaeࠉ〓⸴⥘
Ectocarpalesɻࢩ࣑࢜ࢻࣟ┠Acinetosporaceaeɻ࢔࢟ࢿࢺࢫࢺ࣏ࣛ⛉Acinetosporaceae sp.




࢔࢟ࢿࢺࢫࢺ࣏ࣛ⛉ࡢ୍✀㸦ᬻᐃ㸧






− 152 −䖃⾲ 3-22021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀㈅㢮Table3-2. Mollusca recorded during the Nishinoshima comprehensive scientific research project in
2021
⥘

┠

⛉

Ꮫྡ

໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡBivalviaࠉ஧ᯛ㈅⥘Pectinidaɻ࢖ࢱࣖ࢞࢖┠Pectinidae࢖ࢱࣖ࢞࢖⛉Laevichlamys boninensisࣄࣀࢹࢽࢩ࢟㸦ᗂ㈅㸧

˖Semipallium flavicans ?

ࢽࢩ࢟࢜࢘ࢠ㸽㸦ᗂ㈅㸧

˖

Laevichlamys boninensis ?

ࣄࣀࢹࢽࢩ࢟㸽˖ࢩࣟࣄ࣓࢞࢟㸽࢖ࢱ࣎࢞࢟⛉
㸦ᗂ㈅ࠊ༙∦ࠊྠᐃ୙⬟㸧˖ ˖

Ostreidaɻ࢝࢟┠Ostreidae ࢖ࢱ࣎࢞࢟⛉Nanostrea pinnicola ?
Ostreida sp.

˖yphaeidae ࣋ࢵࢥ࢘࢞࢟⛉Hyotissa quercinus

˖

࣋ࢽ࢞࢟

Pteriida࢘ࢢ࢖ࢫ࢞࢖┠Pteriidae ࢘ࢢ࢖ࢫ࢞࢖⛉Pteriidae sp.

࢘ࢢ࢖ࢫ࢞࢖⛉ࡢ୍✀˖ ˖࢝ࢤࣟ࢘࢞࢖

˖ ˖

Pinnidaeɻࣁ࣎࢘࢟⛉Streptopinna saccata
Gastropodaᕳ㈅⥘Trochida ࢽࢩ࢟࢘ࢬ┠Phasanellidaeࢧࣛࢧࣂ࢖⛉Phasanellidae sp.?

ࢧࣛࢧࣂ࢖⛉㸽㸦ᗂ㈅ࠊྠᐃ୙⬟㸧˖Planaxidae ࢦ࣐ࣇࢽࢼ⛉Hinea fasciata˖ࣚࢥࢫࢪࢱ࣐࢟ࣅࣔࢻ࢟㸦ᗂ㈅㸧

Littorinida ࢚ࢰࢱ࣐࢟ࣅ┠Littorinidae ࢱ࣐࢟ࣅ⛉Littoraria pintadoࢥ࢘ࢲ࢝ࢱ࣐࢟ࣅ

˖

Neogastropoda ᪂⭡ഃ┠
Muricidae ࢔ࢵ࢟࢞࢖⛉Cytharomorula ? sp.

࢝ࢫࣜ࣎ࣛ㏆ఝ✀㸦ᗂ㈅㸧

Mancinella echinata࢘ࢽࣞ࢖ࢩ㸽㸦ᗂ㈅㸧

˖˖

Aplysiida ࢔࣓ࣇࣛࢩ┠Aplysiidae ࢔࣓ࣇࣛࢩ⛉Dolabrifera dolabrifera







ࣅ࣡࢞ࢱࢼ࣓ࢡࢪ









− 153 −˖⾲ 3-32021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀༑⬮⏥Ẇ㢮
Table3-3. Decapoda recorded during the Nishinoshima comprehensive scientific research project in2021⥘ ┠ ⛉ Ꮫྡ໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡMalacostracaɻ㌾⏥⥘
Decapoda䚷䜶䝡┠Penaeidaeɻࢡ࣐࢚ࣝࣅ⛉Metapenaeopsis sp.

˖࢔࢚࢝ࣅᒓࡢ୍✀Rhynchocinetidaeɻࢧࣛࢧ࢚ࣅ⛉Rhynchocinetes conspiciocellus˖ࣖ࢖ࢺࢧࣛࢧ࢚ࣅ

Stenopodidaeɻ࢜ࢺࣄ࣓࢚ࣅ⛉Stenopus hispidus࢜ࢺࣄ࣓࢚ࣅ

˖ͤ

Pilumnidaeɻࢣࣈ࢝࢞ࢽ⛉Zehntneriana novaeinsulicola ?

˖ࢽ࢖ࢪ࣐ࢡࢩࣁ࢞ࢽ"Portunidaeɻ࣡ࢱࣜ࢞ࢽ⛉Cavoportunus dubiusࣚࣟࣥࣄ࣓࢞ࢨ࣑

Gonioinfradens paucidentatusࣚࢶࣁ࢖ࢩ࢞ࢽͤ

Thalamita pictaࣄ࣓࣋ࢽࢶࢣ࢞ࢽͤ

Thalamita spinifera࢖ࣥࢻ࣋ࢽࢶࢣ࢞ࢽ

˖
˖
˖
˖

˖

Xanthidaeɻ࢜࢘ࢠ࢞ࢽ⛉Epiactaea nodulosaࢧ࣓ࣁࢲ࢜࢘ࢠ࢞ࢽࣔࢻ࢟

˖ ˖

Liomera stimpsoniࢫࢸ࢕ࣥࣉࢯࣥ࣋ࢽ࢜࢘ࢠ࢞ࢽ

˖Grapsidaeɻ࢖࣡࢞ࢽ⛉Planes major࢜࢟ࢼ࢞ࣞ࢞ࢽ

䖃Percnidaeɻࢺࢤ࢔ࢩ࢞ࢽ⛉Percnon planissimum˖ࢺࢤ࢔ࢩ࢞ࢽ

˖

Plagusiidaeɻࢩࣙ࢘ࢪࣥ࢞ࢽ⛉Plagusia immaculataࢶࣈ࢖࣎ࢩࣙ࢘ࢪࣥ࢞ࢽ˖※1 ෗┿࡛ࡢ☜ㄆࡢࡳࠋ※2 ᑠ➟ཎึグ㘓✀ࠋ














※1 A species observed by photos. ※2 The species first recorded around Ogasawara Islands.
















− 154 −



⾲ 3-42021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ᗏ⏕⏕≀㸦࣓࢖࢜࣋ࣥࢺࢫ௨እ㸧
Table3-4. Benthos (except meiobenthos in sediments) recorded during the Nishinoshimacomprehensive scientific research project in 2021
⥘

┠

⛉

Ꮫྡ

໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡHydrozoa䚷䝠䝗䝻⹸⥘
Leptothecata
Aglaopheniidae
Aglaophenia sp.
Haleciidae
Halecium sp.
Plumulariigae
Plumlaria sp.
Turbellariaɻ ⹸⥘

ˠ1䖃 䖃 䖃 䖃ࢩࣟ࢞ࣖᒓࡢ୍✀࣍ࢯ࢞ࣖᒓࡢ୍✀䖃ࣁࢿ࢞ࣖᒓࡢ୍✀䖃

Polycladidaɻከᒱ⭠┠Stylochoideaɻࢫࢳࣟࣄ࣒ࣛࢩୖ⛉Planocera cf. reticulata˖ࢶࣀࣄ࣒ࣛࢩ㏆ఝ✀Gastopodaɻ⭡㊊⥘
unidentifiedɻ୙᫂
unidentifiedࠉ୙᫂˖

sp.1
Polychaeta ከẟ⥘
Pyllodocidaɻࢧࢩࣂࢦ࢝࢖┠Polynoidae䚷䜴䝻䝁䝮䝅ୖ⛉˖

sp.1
Phyllodocidaeɻࢧࢩࣂࢦ࢝࢖⛉˖

sp.1
Syllidaeɻࢩࣜࢫ⛉˖

sp.1
Terebellidaɻࣇࢧࢦ࢝࢖┠Terebellidae/Terebellinaeɻࣇࢧࢦ࢝࢖⛉/Terebellinaeள⛉
˖

sp.1

˖

sp.2
˖

sp.3
Sabellidaɻࢣ࣒ࣖࣜࢩ┠Serpulidaeɻ࢝ࣥࢨࢩࢦ࢝࢖⛉˖

sp.1
Phascolosomatidea䚷ࢧ࣓ࣁࢲ࣍ࢩ࣒ࢩ⥘Phascolosomatida䚷䝃䝯䝝䝎䝩䝅䝮䝅⛉unidentifiedɻ୙᫂

˖

sp.1

※1 ෗┿࡛ࡢ☜ㄆࡢࡳࠋ




※1 A species observed by photos. 






− 155 −



⾲ 3-4⥆ࡁ
Table. 3-4. Continued⥘ ┠ ⛉ Ꮫྡ໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡPycnogonida䚷䜴䝭䜾䝰⥘
Pantopoda䚷䜴䝭䜾䝰┠
Rhynchothoracidaeɻ࢖࣑࣎࢘ࢢࣔ⛉
˖

sp.1

˖

sp.2
˖

sp.3
Crustacea䚷⏥Ẇ⥘
Calanoidaɻ࢝ࣛࢾࢫ┠˖

sp.1
Thecostracaɻࣇࢪࢶ࣎ୖ┠Balanidaeɻࣇࢪࢶ࣎⛉Megabalanus occator࣑ࢼ࣑࢔࢝ࣇࢪࢶ࣎

˖

Balanus trigonusࢧࣥ࢝ࢡࣇࢪࢶ࣎

˖

Amphipodaɻ➃⬮┠Phronimoideaɻࢼ࢞ࣄࢤ࣑࢘ࣀ࣑ୖ⛉˖

sp.1
Stenolaemataɻ⊃ႃ⥘
Cyclostomataɻ෇ཱྀ┠Tubuliporidaeɻࢡࢲࢥࢣ࣒ࢩ⛉˖ ˖Tubulipora sp. 1
Tubulipora sp. 2ࢡࢲࢥࢣ࣒ࢩࡢ୍✀Exidmonea sp.

ࢡࢲࢥࢣ࣒ࢩ⛉ࡢ୍✀




















− 156 −

˖ ˖ ˖
˖

˖ ˖ ˖



⾲ 3-4⥆ࡁ
Table. 3-4. Continued
⥘

┠

⛉

Ꮫྡ

໭ഃ St. St. St. St. St. St. St. St.
ࡢ☾ E1 E2 E3 A S1 S2 S3 S4࿴ྡGymnolaemataɻ〄ႃ⥘Ctenostomatidaɻཱྀ᷸┠Triticellidae
Triticella sp.

7ULWLFHOOD ᒓࡢ୍✀˖㸦ᮍグ㍕✀㸧

Cheilostomatidaɻ၁ཱྀ┠Aeteidaeɻࣁ࢖ࢥࢣ࣒ࢩ⛉Aetea sp.

ࣁ࢖ࢥࢣ࣒ࢩ⛉ࡢ୍✀˖˖ ˖Catenicellidaeɻࢪࣗࢬࢶࢼࢠࢥࢣ࣒ࢩ⛉Catenicella sp.

˖ࢪࣗࢬࢶࢼࢠࢥࢣ࣒ࢩ

Lepraliellidaeɻ࢖ࢱࢥࣈࢥࢣ࣒ࢩ⛉Drepanophora sp.

˖'UHSDQRSKRUD ᒓࡢ୍✀Romancheinidaeɻࣔࣟࢸࢥࢣ࣒ࢩ⛉Hippomenella sp.

˖+LSSRPHQHOOD ᒓࡢ୍✀Escharinidae䚷Escharinidae⛉
Escharina sp.

˖࣑ࢬ࢝࢟ࢥࢣ࣒ࢩࡢ୍✀Smittinidaeɻࣁࢢࢳࢥࢣ࣒ࢩ⛉Pleurocodonellina sp.

ࣁࢢࢳࢥࢣ࣒ࢩࡢ୍✀˖ ˖ࣁࢢࢳࢥࢣ࣒ࢩ⛉ࡢ୍✀˖ ˖

Phidoloporidaeɻ࢔࣑ࢥࢣ࣒ࢩ⛉Reteporellina cf. denticulata࣑ࢧ࢟࢔࣑ࢥࢣ࣒ࢩ㏆ఝ✀Rhynchozoon sp.

࢝ࢢࢶࢳࢥࢣ࣒ࢩࡢ୍✀

˖

˖ ˖
˖

Echinoideaɻ࢘ࢽ⥘unidentifiedɻ୙᫂
unidentifiedɻ୙᫂
sp.1

˖

sp.2

˖

Piscesɻ㨶⥘
Perciformesɻࢫࢬ࢟┠Creediidaeɻࢺࣅࢠ࣏ࣥ⛉Limnichthys fasciatus










ࢺࣅࢠ࣏ࣥ












− 157 −˖⾲ 3-52021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ᗏ㉁୰ࡢ࣓࢖࢜࣋ࣥࢺࢫ
Table 3-5. Meiobenthos recorded in sediments during the Nishinoshima comprehensive scientificresearch project in 2021
⥘ ┠ ⛉ ᏛྡSt. St.
໭ഃ St. St. St. St.
St.S1
St.S4
ࡢ☾ E1 E2 E3 A
S2 S3

࿴ྡ

Globothalamea
Rotaliida
Rotalinidae
˖Rosalina globularis
Chromadoreaɻࢡ࣐ࣟࢻࣛள⥘Desmodorida
Draconematidae

˖

sp.1

˖

sp.2
Polychaeta ከẟ⥘
Pyllodocidaɻࢧࢩࣂࢦ࢝࢖┠Sigalionidae⛉ʤPisioninaeள⛉ʥࣀࣛࣜ࢘ࣟࢥ࣒ࢩ⛉˖ᶆPisione sp.

˖ ᶇᶈ

Polynoidae⛉ɻ (Lepidonotinaeள⛉)ɻ࢘ࣟࢥ࣒ࢩ⛉
sp.3

ᶇ

sp.4

ᶈ

Phascolosomatidea ࢧ࣓ࣁࢲ࣍ࢩ࣒ࢩ⥘Phascolosomatida
unidentifiedɻ୙᫂˖

sp.2
Crustacea䚷⏥Ẇ⥘Harpacticoida‫┠ࢥࣥࢪ࣑ࢥࢯؙ‬unidentifiedࠉ୙᫂˖

sp.1

˖ᶆ ˖ ˖ ᶇᶈ
ᶆ

sp.2

˖ ᶇᶈ
˖

sp.3
ᶅ

sp.4

ᶇ
ᶇᶈ

Stenolaemataࠉ⊃ႃ⥘
Cyclostomataࠉ෇ཱྀ┠Tubuliporidaeࠉࢡࢲࢥࢣ࣒ࢩ⛉Tubulipora sp. 2

ᶇࢡࢲࢥࢣ࣒ࢩࡢ୍✀Gymnolaemataɻ〄ႃ⥘
Cheilostomatidaɻ၁ཱྀ┠unidentifiedɻ୙᫂-၁ཱྀ┠ࢥࢣ࣒ࢩࡢึᮇ⩌య

Echinoideaɻ࢘ࢽ⥘unidentifiedࠉ୙᫂
unidentifiedࠉ୙᫂
˖

sp.3

ᶇ

sp.4

ձSt.S1:26.7mɼղSt.S1:13.6mɼճSt.S4:29.8mɼմSt.S4:18.7m

− 158 −



⾲ 42021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ື≀ࣉࣛࣥࢡࢺࣥ
Table 4. Plankton recorded during Nishinoshima comprehensive scientific research project in 2021
㛛

⥘

┠

⛉

Ꮫྡ

St. St. St. St. St. St. St. St.
St. Pᮾഃ
PN PNE PE PSE PS PSW PW PNW ᪥ἐ1hᚋ࿴ྡCtenophoraࠉ᭷᷸ື≀㛛
Tentaculataࠉ᭷ゐᡭ⥘
cydippid larvae˖ࣇ࢘ࢭࣥࢡࣛࢤᆺᗂ⏕Cnidaria ่⬊ື≀㛛Hydrozoa ࣄࢻࣟ⹸⥘Anthomedusae ⰼࢡࣛࢤ┠Eucodoniidae ࢥࣔࣜࢡࣛࢤ⛉Eucodonium sp.

˖ࢥࣔࣜࢡࣛࢤࡢ㸯✀

˖

˖

˖

˖

˖

˖

Limnomedusae ῐỈࢡࣛࢤ┠
Geryoniidae ࢜࢜࢝ࣛ࢝ࢧࢡࣛࢤ⛉Liriope tetraphylla࢝ࣛ࢝ࢧࢡࣛࢤ

˖˖˖

Trachymedusae ◳ࢡࣛࢤ┠
Trachymedusaeࠉsp.1◳ࢡࣛࢤ┠ࡢ㸯✀˖

Trachymedusaeࠉsp.2◳ࢡࣛࢤ┠ࡢ㸯✀˖

Siphonophorae ࢡࢲࢡࣛࢤ┠Diphyidae ࣇࢱࢶࢡࣛࢤ⛉˖˖Diphyes sp1

ࣇࢱࢶࢡࣛࢤᒓࡢ㸯✀Diphyes sp2

ࣇࢱࢶࢡࣛࢤᒓࡢ㸯✀

Lensia sp.

ࢥࣇࢱࢶࢡࣛࢤᒓࡢ㸯✀˖Abylopsis eschscholtzii

ࢥࣁࢥࢡࣛࢤࣔࢻ࢟

˖

Bassia bassensisࢺ࢘ࣟ࢘ࢡࣛࢤ

˖

Abyla sp.

ࣁࢥࢡࣛࢤᒓࡢ㸯✀

˖

˖

˖

˖

˖

˖

Abylidae ࣁࢥࢡࣛࢤ⛉
˖

˖

˖

˖
˖

˖
˖

Prayidae ࢔࢖࢜࢖ࢡࣛࢤ⛉Praya sp.

˖࢔࢖࢜࢖ࢡࣛࢤࡢ㸯✀Annelida ⎔ᙧື≀㛛
3RO\FKDHWDከẟ⥘
Phyllodocidaࠉࢧࢩࣂࢦ࢝࢖┠Typhloscolecidae ࣒ࣖࢩࢦ࢝࢖⛉Typhloscolex sp.

˖ࢸ࢕ࣇࣟࢫࢥࣞࢵࢡࢫᒓࡢ㸯✀

˖

˖

˖

˖

Phyllodocidae ࢧࢩࣂࢦ࢝࢖⛉Vanadis longissima˖࢔࢟ࢶ࢘࢟ࢦ࢝࢖

Nectochaeta
Nectochaeta larvae sppࢿࢡࢺ࣮࢟ࢱᗂ⏕(」ᩘ✀㸧 ✀㸧˖࣋ࣜࢪ࣮ࣕᗂ⏕ 」ᩘ✀㸧

˖

˖

˖

˖

˖

˖

˖

˖

˖

Mollusca ㌾యື≀㛛Bivalvia ஧ᯛ㈅⥘Veliger larva Veliger larva

˖

Gastropoda ⭡㊊⥘
Sorbeoconcha ྾⭍┠
Atlantidae ࢡࢳ࢟ࣞ࢘࢟࢞࢖⛉Atlanta spp

ࢡࢳ࢟ࣞ࢘࢟࢞࢖ᒓࡢ」ᩘ✀㸦㸲✀㸧 ˖

˖

˖

˖

˖

˖

˖

˖

˖

Pterotracheidae. ࣁࢲ࢝ࢰ࢘ࢡࣛࢤ⛉Pterotrachea coronata˖ࣁࢲ࢝ࢰ࢘ࢡࣛࢤ

Pteropoda ⩼㊊┠
Limacinidae ࣑ࢪ࣐ࣥ࢘࢟࢖࣐࢖⛉Limacina spp.

˖࣑ࢪ࣐ࣥ࢘࢟࢖࣐࢖ᒓࡢ」ᩘ✀ 㸰✀㸧˖˖Creseidae ࢘࢟ࢷࣀ࢞࢖⛉Creseis spp.
Veliger larva Veliger larva࢘࢟ࢷࣀ࢞࢖ᒓࡢ」ᩘ✀ 㸰✀㸧࣋ࣜࢪ࣮ࣕᗂ⏕ 」ᩘ✀㸧






− 159 −

˖
˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖



⾲ 4⥆ࡁ
Table 4. Continued
㛛

⥘

┠

⛉

Ꮫྡ

St. St. St. St. St. St. St. St.
St. Pᮾഃ
PN PNE PE PSE PS PSW PW PNW ᪥ἐ1hᚋ࿴ྡArthropoda ⠇㊊ື≀㛛Crustacea ⏥Ẇள㛛Branchiopoda 㪰⬮⥘
Diplostraca ཮Ẇ┠
Podonidae ࣑࣓࣑࢘࢜࢜ࢪࣥࢥ⛉Pseudevadne tergestinaࢺࢤࢼࢩ࢚࣎ࢩ࣑ࢪࣥࢥ

Evadne spiniferaࢺࢤ࢚࣎ࢩ࣑ࢪࣥࢥ

Podon leuckarti࣑࣓࣑࢜࢜࢘࢜࢜ࢪࣥࢥ

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

Ostracoda ㈅ᙧ⹸⥘Ostracoda sp.

˖

㈅ᙧ⹸㢮

Maxillopoda Dahl, 1956 㢡⬮⥘
Copepoda ࢝࢖࢔ࢩள⥘Calanoida Sars, 1903 ࢝ࣛࢾࢫ┠࢝ࣛࢾࢫ┠㢮

˖

˖

˖

˖

˖

˖

˖

˖

˖

Oithona sp.1

࢜࢖ࢺࢼᒓࡢ㸯✀VS

˖

˖

˖

˖

˖

˖

˖

˖

˖

Oithona sp.2

࢜࢖ࢺࢼᒓࡢ㸯✀sp2

˖˖

Calanouda spp.
Cyclopoida ࢟ࢡࣟࣉࢫ┠Oithonidae࢜࢖ࢺࢼ⛉˖˖Poecilostomatoida ࣏࢚࢟ࣟࢫࢺ࣒┠Corycaeidae ࢥࣜࢣ࢘ࢫ⛉Corycaeidae sp.1

ࢥࣜࢣ࢘ࢫ⛉ࡢ㸯✀

˖

˖

˖

˖

˖

˖

˖

˖

˖

Corycaeidae sp.2

ࢥࣜࢣ࢘ࢫ⛉ࡢ㸯✀

˖

˖

˖

˖

˖

˖

˖

˖

˖

Corycaeidae sp.3

ࢥࣜࢣ࢘ࢫ⛉ࡢ㸯✀

˖

˖

˖

˖

˖

˖

˖

˖

˖

Corycaeidae sp.4

ࢥࣜࢣ࢘ࢫ⛉ࡢ㸯✀

Corycaeidae sp.5ࢥࣜࢣ࢘ࢫ⛉ࡢ㸯✀˖˖

Corycaeidae spp.

ࢥࣜࢣ࢘ࢫ⛉ࡢ」ᩘ✀

˖

˖

˖

˖

˖

˖

˖
˖
˖

˖

˖

˖

˖

˖

˖

˖

Oncaeidae ࢜ࣥࢣ࢔⛉Oncaea sp.1

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.1

˖Oncaea sp.2

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.2

˖Oncaea sp.3

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.3

˖

˖

˖

Oncaea sp.4

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.4

˖

˖

˖

Oncaea sp.5࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.5

˖Oncaea sp.6

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.6

˖Oncaea sp.7

࢜ࣥࢣ࢔ᒓࡢ㸯✀sp.7

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖
˖

˖

˖

˖

Sapphirinidaeࠉࢧࣇ࢕ࣜࢼ⛉Copilia sp.1

ࢥࣆࣜ࢔ᒓࡢ㸯✀VS

Copilia sp.2

ࢥࣆࣜ࢔ᒓࡢ㸯✀VS

Sapphirina sp.1

ࢧࣇ࢕ࣜࢼᒓࡢ㸯✀sp.1

Sapphirina sp.2

ࢧࣇ࢕ࣜࢼᒓࡢ㸯✀sp.2

˖

˖

˖

˖

˖

˖
˖

˖
˖

Harpacticoida ࣁࣝࣃࢡࢳࢡࢫ┠Ectinosomatidae ࣇࢿ࢞ࢱࢯࢥ࣑ࢪࣥࢥ⛉Microsetella rosea࢔࢝࢜ࣚࢠࢯࢥ࣑ࢪࣥࢥ

Microsetella norvegica࢜ࣚࢠࢯࢥ࣑ࢪࣥࢥ

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖
˖

Clytemnestridae ࢡࣜࢸ࣒ࢿࢫࢺࣛ⛉Clytemnestra scutellata˖ࢡࣜࢸ࣒ࢿࢫࢺࣛ ࢫࢡࢸࣛࢱ

Nauplius larvae
Nauplius larvae




˖

ࣀ࣮ࣉࣜ࢘ࢫᗂ⏕






− 160 −

˖

˖

˖

˖

˖

˖

˖

˖



⾲ 4⥆ࡁ
Table 4. Continued
㛛

⥘

┠

⛉

Ꮫྡ

St. St. St. St. St. St. St. St.
St. Pᮾഃ
PN PNE PE PSE PS PSW PW PNW ᪥ἐ1hᚋ࿴ྡMalacostraca ㌾⏥⥘
Decapoda ༑⬮┠
Dendrobranchiata ᰿㪰ள┠
Luciferidae ࣓࢚ࣘࣅ⛉Lucifer sp.

˖࣓࢚ࣘࣅࡢ㸯✀

˖

˖

˖

㛗ᑿ㢮ᗂ⏕
˖

ࢰ࢚࢔ᗂ⏕VS˖˖ࢰ࢚࢔ᗂ⏕VS˖ࢰ࢚࢔ᗂ⏕VS˖ࢰ࢚࢔ᗂ⏕VSࢰ࢚࢔ᗂ⏕VS˖ࢰ࢚࢔ᗂ⏕VS˖

Pleocyemata ᢪ༸ள┠Brachyura ▷ᑿୗ┠
▷ᑿ㢮ᗂ⏕

˖

ࢰ࢚࢔ᗂ⏕VS˖ࢰ࢚࢔ᗂ⏕VS
Amphipoda ➃⬮┠Gammarida ࣚࢥ࢚ࣅୗ┠Gammarida sp.

˖ࣚࢥ࢚ࣅࡢ㸯✀Chaetognatha ẟ㢡ື≀㛛
Sagittoidea ⌧⏕▮⹸⥘
Aphragmophora ↓⭷➽┠
Sagittidae ▮⹸⛉
Sagittidae spp.

˖࣒ࣖࢩ⛉ࡢ」ᩘ✀ 㸲✀㸧

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

˖

Chordata ⬨⣴ື≀㛛
Thaliacea ࢱࣜ࢔⥘Doliolida ࣑࢘ࢱࣝ┠Doliolidae ࣑࢘ࢱࣝ⛉Doliolidae sp.

˖࣑࢘ࢱࣝ⛉ࡢ㸯✀˖

Appendicularia ᑿ⹸⥘
Appendicularia ᑿ⹸┠࢜ࢱ࣐࣎ࣖ㢮ࡢ」ᩘ✀㸦㸱✀㸧

˖

༸

˖

˖

˖

˖

˖

˖

˖

˖

˖

Vertebrata ⬨᳝ື≀ள㛛
Pisciformes 㨶㢮
⛶㨶























− 161 −˖˖˖

⾲ 52021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀᧜ᙳ࡛☜ㄆࡉࢀࡓ㨶㢮
Table 5. Fish recorded during the Nishinoshima comprehensive scientific research project in 2021
┠ ⛉

Ꮫྡ

࿴ྡ

St.S1 St.S2 St.S3 St.S4 St.A

Carcharhiniformesࠉ࣓ࢪࣟࢨ࣓┠Carcharhinidaeࠉ࣓ࢪࣟࢨ࣓⛉Carcharhinus galapagensis࢞ࣛࣃࢦࢫࢨ࣓

‫ە‬

Beryciformesࠉ࣓࢟ࣥࢲ࢖┠
Holocentridaeࠉ࢖ࢵࢺ࢘ࢲ࢖⛉Myripristis berndti

࢔࣐࢝ࢶ࢝ࢧ

‫ە‬

Perciformesࠉࢫࢬ࢟┠Serranidaeࠉࣁࢱ⛉Epinephelus fasciatus

࢔࢝ࣁࢱ

Epinephelus hexagonatus࢖ࢩ࢞࢟ࣁࢱ

Plectropomus leopardus

ࢫࢪ࢔ࣛ

Pseudanthias cooperi࢝ࢩ࣡ࣁࢼࢲ࢖

Pseudanthias pascalusࣁࢼࢦ࢖Pseudanthias squamipinnis࢟ࣥࢠࣙࣁࢼࢲ࢖

‫ە‬

‫ە‬

‫ە‬

‫ە‬
‫ە‬
‫ە‬
‫ە‬
‫ە‬

‫ە‬

‫ە‬
‫ە‬

Apogonidaeࠉࢸࣥࢪࢡࢲ࢖⛉Ostorhinchus fukuiiࣇࢱࢫࢪ࢖ࢩࣔࢳ

Apogonidae sp.

ࢸࣥࢪࢡࢲ࢖⛉ࡢ୍✀

‫ە‬
‫ە‬

‫ە‬

Carangidaeࠉ࢔ࢪ⛉Elagatis bipinnulata

ࢶ࣒ࣈࣜ

‫ە‬

Caranx lugubris

࢝ࢵ࣏ࣞ

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

Lutjanidaeࠉࣇ࢚ࢲ࢖⛉Lutjanus kasmiraࣚࢫࢪࣇ࢚ࢲ࢖

Lutjanus stellatus

ࣇ࢚ࢲ࢖

‫ە‬

‫ە‬

Caesionidaeࠉࢱ࢝ࢧࢦ⛉Caesio teres࣓࢘࢖ࣟࣔࢻ࢟

‫ە‬

Lethrinidaeࠉࣇ࢚ࣇ࢟ࢲ࢖⛉Gymnocranius euanus

ࢩࣟࢲ࢖

‫ە‬

Sparidaeࠉࢱ࢖⛉Oplegnathus punctatus࢖ࢩ࢞࢟ࢲ࢖

‫ە‬

Parupeneus ciliatus࣍࢘ࣛ࢖ࣄ࣓ࢪ

‫ە‬

Parupeneus insularisࣇࢱ࢜ࣅ࣑ࢼ࣑ࣄ࣓ࢪ

‫ە‬

Mullidaeࠉࣄ࣓ࢪ⛉Chaetodontidaeࠉࢳࣙ࢘ࢳࣙ࢘࢘࢜⛉Chaetodon daedalmaࣘ࢘ࢮࣥHeniochus diphreutes࣒ࣞࣁࢱࢱࢸࢲ࢖

‫ە‬
‫ە‬

‫ە‬
‫ە‬

‫ە‬
‫ە‬

‫ە‬

Pomacanthidaeࠉ࢟ࣥࢳࣕࢡࢲ࢖⛉Centropyge interrupta




ࣞࣥࢸࣥࣖࢵࢥ



− 162 −‫ە‬

⾲ 5⥆ࡁ
Table 5. Continued
┠ ⛉

Ꮫྡ

࿴ྡ

St.S1 St.S2 St.S3 St.S4 St.A

Perciformesࠉࢫࢬ࢟┠Pomacentridaeࠉࢫࢬ࣓ࢲ࢖⛉Abudefduf vaigiensis࢜ࣖࣅࢵࢳࣕ

Chromis acaresࢥࣅࢺࢫࢬ࣓ࢲ࢖

‫ە‬

Chromis alleni࢜ࢼ࢞ࢫࢬ࣓ࢲ࢖

‫ە‬

Chromis margaritiferaࢩࢥࢡࢫࢬ࣓ࢲ࢖

Chromis vanderbiltiࣄ࣓ࢫࢬ࣓ࢲ࢖

Plectroglyphidodon johnstonianus࣓ࣝࣜ࢖ࢩ࢞࢟ࢫࢬ࣓ࢲ࢖Stegastes insularisࣚࣟࣥࢫࢬ࣓ࢲ࢖

‫ە‬࣑ࢼ࣑࢖ࢫࢬ࣑

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬

‫ە‬
‫ە‬

Kyphosidaeࠉ࢖ࢫࢬ࣑⛉Kyphosus pacificus
Labridaeࠉ࣋ࣛ⛉Bodianus leucostictus

࢟ࢶࢿ࣋ࣛCoris gaimard

ࢶࣘ࣋ࣛGomphosus varius

ࢡࢠ࣋ࣛ

‫ە‬

Halichoeres biocellatusࢽࢩ࢟࢟ࣗ࢘ࢭࣥ

‫ە‬

Halichoeres orientalis

ࢶ࢟࣋ࣛ

‫ە‬

Hemigymnus melapterusࢱࣞࢡࢳ࣋ࣛ

‫ە‬

Labroides dimidiatus࣍ࣥࢯ࣓࣡ࢣ࣋ࣛ

Thalassoma amblycephalumࢥ࢞ࢩࣛ࣋ࣛ

‫ە‬

Thalassoma lutescens࣐ࣖࣈ࢟࣋ࣛ

‫ە‬ࢺࣛࢠࢫᒓࡢ୍✀‫ە‬ࢸࣥࢡࣟࢫࢪࢠ࣏ࣥ

‫ە‬

‫ە‬
‫ە‬
‫ە‬

‫ە‬

‫ە‬
‫ە‬

‫ە‬

Pinguipedidaeࠉࢺࣛࢠࢫ⛉Parapercis sp.
Blenniidaeࠉ࢖ࢯࢠ࣏ࣥ⛉Plagiotremus tapeinosoma‫ە‬Gobiidaeࠉࣁࢮ⛉Gnatholepis sp.1

࢜࢜ࣔࣥࣁࢮᒓࡢ୍✀1‫ە‬Ephippidaeࠉ࣐ࣥࢪࣗ࢘ࢲ࢖⛉Platax teira

ࢶࣂ࣓࢘࢜

‫ە‬

Zanclidaeࠉࢶࣀࢲࢩ⛉Zanclus cornutus

ࢶࣀࢲࢩ

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Acanthuridaeࠉࢽࢨࢲ࢖⛉Acanthurus leucopareiusࢫࢪࢡࣟࣁࢠ

Acanthurus olivaceusࣔࣥࢶ࢟ࣁࢠ

Naso hexacanthusࢸࣥࢢࣁࢠࣔࢻ࢟

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Scombridaeࠉࢧࣂ⛉Gymnosarda unicolor

࢖ࢯ࣐ࢢࣟ

‫ە‬

࣑ࢰࣞࣇࢢ

‫ە‬

Tetraodontiformesࠉࣇࢢ┠Tetraodontidaeࠉࣇࢢ⛉Arothron meleagris− 163 −



⾲ 6-12021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀⁻ὶ≀࡛☜ㄆࡉࢀࡓ⸴㢮
Table 6-1. Fucistia on drifting objects recorded during the Nishinoshima comprehensive scientificresearch project in 2021
⥘ ┠ ⛉ Ꮫྡ

࿴ྡ

࣮ࣟࣉ

㛗㠐

ࡦࡶ௚

Წ

࢝ࢦ

ࢥ࣮ࣄ࣮
ࡢᐜჾ

Phaeophyceaeɻ〓⸴⥘
Ectocarpalesɻࢩ࣑࢜ࢻࣟ┠Acinetosporaceaeɻ࢔࢟ࢿࢺࢫࢺ࣏ࣛ⛉Acinetosporaceae sp.

࢔࢟ࢿࢺࢫࢺ࣏ࣛ⛉ࡢ୍✀㸦ᬻᐃ㸧˖

Fucalesɻࣄࣂ࣐ࢱ┠Sargassaceaeɻ࣍ࣥࢲ࣡ࣛ⛉˖Hormophysa cuneiformis ࣖࣂࢿࣔࢡ

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⾲ 6-22021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ ⁻ὶ≀࡛☜ㄆࡉࢀࡓ㈅㢮
Table 6-2. Mollusca on drifting objects recorded during the Nishinoshima comprehensive scientificresearch project in 2021
⥘

┠

⛉

Ꮫྡ

࿴ྡ

࣮ࣟࣉ 㛗㠐 ࡦࡶ௚ Წ ࢝ࢦ

ࢥ࣮ࣄ࣮
ࡢᐜჾ

Bivalviaɻ஧ᯛ㈅⥘Mytilida ࢖࢞࢖┠Mytilidaeɻ࢖࢞࢖⛉Brachidontes mutabilisࣄࣂࣜ࢞࢖ࣔࢻ࢟

˖

Septifer sp.

࢖࢞࢖ࡢ୍✀

˖

࢘࢟ࢶ࣎

˖

ࢥ࣒ࢠࢶࣈ

˖

Cerithiida ࢜ࢽࢶࣀ࢞࢖┠Ltiopidae ࢘࢟ࢶ࣎⛉Litiopa nipponica

˖Cypraeida ࢱ࢝ࣛ࢞࢖┠Triviidaeࢩࣛࢱ࣐⛉Trivirostra hordacea
Nudibranchia 〄㪰┠
Fionoidea ࣄࢲ࣑ࣀ࣑࢘࢘ࢩୖ⛉Flonoidea sp.

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˖

ࣄࢲ࣑ࣀ࣑࢘࢘ࢩୖ⛉ࡢ୍✀
⾲ 6-32021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀ ⁻ὶ≀࡛☜ㄆࡉࢀࡓ༑⬮⏥Ẇ㢮
Table 6-3. Decapoda on drifting objects recorded during the Nishinoshima comprehensive scientificresearch project in 2021
⥘

┠

⛉

Ꮫྡ

࿴ྡ

࣮ࣟࣉ 㛗㠐 ࡦࡶ௚ Წ ࢝ࢦ

ࢥ࣮ࣄ࣮
ࡢᐜჾ

Malacostracaɻ㌾⏥⥘
Decapoda䚷䜶䝡┠Grapsidaeɻ࢖࣡࢞ࢽ⛉Planes major࢜࢟ࢼ࢞ࣞ࢞ࢽ

˖˖Planes marinus

ࢼ࢞ࣞ࢞ࢽ

˖

˖

Plagusiidaeɻࢩࣙ࢘ࢪࣥ࢞ࢽ⛉Plagusia immaculata

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ࢶࣈ࢖࣎ࢩࣙ࢘ࢪࣥ࢞ࢽ

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− 164 −˖⾲ 6-42021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀⁻ὶ≀࡛☜ㄆࡉࢀࡓ㈅㢮࣭༑⬮⏥Ẇ㢮௨እࡢ↓⬨᳝ື≀
Table 6-4. Invertebrate (except Mollusca and Decapoda) on drifting objects recorded during the
Nishinoshima comprehensive scientific research project in 2021
⥘

┠

⛉ Ꮫྡ

࿴ྡ

࣮ࣟࣉ 㛗㠐 ࡦࡶ௚ Წ ࢝ࢦ

ࢥ࣮ࣄ࣮
ࡢᐜჾ

Anthozoaࠉⰼ⹸⥘Actiniariaɻ࢖ࢯࢠࣥࢳࣕࢡ┠Aiptasiidaeɻࢭ࢖ࢱ࢝࢖ࢯࢠࣥࢳࣕࢡ⛉Exaiptasia cf. pallida (=Exaiptasia diaphana ?)ࢳࢠࣞ࢖ࢯࢠࣥࢳࣕࢡ㏆ఝ✀˖ࢧࣥࣁࢳ࢘ࣟࢥ࣒ࢩ㏆ఝ✀˖˖Polychaeta ከẟ⥘
Phyllodocidaࠉࢧࢩࣂࢦ࢝࢖┠Polynoidae (Lepidonotinaeள⛉)ɻ࢘ࣟࢥ࣒ࢩ⛉Hermilepidonotus cf. helotypus
unidentifiedɻ෈໎˖

sp.2
Amphinomidaɻ࣑࢘ࢣ࣒ࢩ┠Amphinomidaeɻ࣑࢘ࢣ࣒ࢩ⛉˖

sp.1
Opheliidaɻ࢜ࣇ࢙ࣜ࢔┠Opheliidaeɻ࢜ࣇ࢙ࣜ࢔ࢦ࢝࢖⛉˖

sp.1
Turbellariaɻ ⹸⥘
Polycladidaɻከᒱ⭠┠Stylochoideaɻࢫࢳࣟࣄ࣒ࣛࢩୖ⛉˖

sp.1
Gymnolaemataɻ〄ႃ⥘
Cheilostomatidaࠉ၁ཱྀ┠Membraniporidaeɻ࢔࣑࣓ࢥࢣ࣒ࢩ⛉Membranipora sp.

࢔࣑࣓ࢥࢣ࣒ࢩࡢ୍✀˖

Jellyella cf. eburneaࢧ࣓ࣁࢲࢥࢣ࣒ࢩᒓࡢ୍✀˖ࢧ࣓ࣁࢲ࣍ࢩ࣒ࢩ㏆ఝ✀˖

Phascolosomatidea䚷ࢧ࣓ࣁࢲ࣍ࢩ࣒ࢩ⥘Phascolosomatida
Phascolosomatidaeɻࢧ࣓ࣁࢲ࣍ࢩ࣒ࢩ⛉Phascolosoma cf. scolops
Crustacea䚷⏥Ẇ⥘
Calanoidaɻ࢝ࣛࢾࢫ┠˖

sp.1
Thecostracaɻࣇࢪࢶ࣎ୖ┠Lepadidaeɻ࢚࣎ࢩ࢞࢖⛉Lepas (Anatifa ) anserifera

࢚࢝ࣝ࣎ࢩ

˖

˖

˖

˖

˖

Isopoda‫┠⬮➼ؙ‬
Munnidaeɻ࣒ࣥࢼ⛉˖

sp.1
Amphipodaɻ➃⬮┠Ampithoidaeɻࣄࢤࢼ࢞ࣚࢥ࢚ࣅ⛉sp.1

ࢽࢵ࣏ࣥࣔࣂࣚࢥ࢚ࣅ
㏆ఝ✀ࢆ୰ᚰ࡜ࡋࡓ」ᩘ✀

sp.2

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− 165 −˖˖⾲ 6-52021 ᖺᗘすஅᓥ⥲ྜᏛ⾡ㄪᰝ࡟࠾ࡅࡿ☜ㄆ✀⁻ὶ≀࡛☜ㄆࡉࢀࡓ㨶㢮
Table 6-5. Fish with drifting objects recorded during the Nishinoshima comprehensive scientificresearch project in 2021
⥘

┠

⛉

Ꮫྡ

࿴ྡ

࣮ࣟࣉ 㛗㠐 ࡦࡶ௚ Წ ࢝ࢦ

ࢥ࣮ࣄ࣮
ࡢᐜჾ

Piscesɻ㨶⥘
Lophiiformesɻ࢔ࣥࢥ࢘┠Antennariidaeɻ࢚࢝ࣝ࢔ࣥࢥ࢘⛉ɻ

Histrio histrio

ࣁࢼ࢜ࢥࢮ

˖

࢜ࣖࣅࢵࢳࣕ

˖࢖ࢫࢬ࣑⛉ࡢ୍✀˖

Perciformesɻࢫࢬ࢟┠Pomacentridaeɻࢫࢬ࣓ࢲ࢖⛉Abudefduf vaigiensis
Kyphosidaeࠉ࢖ࢫࢬ࣑⛉Tetraodontiformesɻࣇࢢ┠Balistidaeɻࣔࣥ࢞ࣛ࢝࣡ࣁࢠ⛉Canthidermis maculata

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− 166 −

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OGASAWARA RESEARCH

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SUMMARY

Preliminary report of marine macrofauna of Nishinoshima Island

Yuka TOYOYA (KOYANO) 1*, Masato HIROSE2, Tomoyuki NAKANO3,

Hironori KOMATSU4, Ryuta TERADA5, Takashi TOYOFUKU6, 7, Yukiko NAGAI4, 6,



Hitoshi IMAI1, Yusuke OYAMADA1, Akitsugu MUKAI8, Dairo KAWAGUCHI8,



Haruo TAKAMINE9，Ryuichi MINATO1, Hideaki MORI1 & Hiroshi MIYAKE2

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1. Japan Wildlife Research Center, 3-3-7 Kotobashi, Sumida, Tokyo 130-8606, Japan.
2. Kitasato University, 1-15-1 Kitasato, Minami, Sagamihara, Kanagawa 252-0373, Japan.
3. Seto Marine Biological Laboratory, Field Science and Education Center, Kyoto University, 459
Shirahama, Nishimuro, Wakayama 649-2211, Japan.
4. Natural Museum of Nature and Science, 1-12-30 Amakubo, Tsukuba, Ibaraki 305-0005, Japan.
5. The United Graduate School of Agricultural Sciences Kagoshima University, 1-21-24 Koorimoto,Kagoshima, Kagoshima 890-0065, Japan.
6. X-Star, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15
Natsushima-cho, Yokosuka, Kanagawa 237-0061, Japan.
7. Tokyo University of Marine Science and Technology (TUMSAT), 4-5-7 Konan, Minato, Tokyo
108-8477, Japan.
8. Islands Care, Shizusawa, Hahajima, Ogasawara, Tokyo 100-2211, Japan.
9. HARUKA-MARU, Kiyose, Chichijima, Ogasawara, Tokyo 100-2101, Japan.
*ytoyota@jwrc.or.jp (author for correspondence)

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The environment and marine macrofauna around Nishinoshima Island were investigated in July
2021. Muddy seawater was observed west of the island, probably due to the volcanic eruption. The
seabed off the island's north was covered by volcanic ash and lava over 3 m, and pointed rocks thatlooked like volcanic bombs dotted the area. During this survey, over 253 species in 14 phyla wereobserved, mainly on the northern beach and in the northern sea. The biodiversity of benthic animals
was low; therefore, macroalgae and corals were not observed. Hydrozoa and Bryozoa wereabundant on the seabed rocks. Since they advance on the bare seabed when the marine benthic
ecosystem recovers, this indicates that the benthic fauna around Nishinosima is in the early conveyed
status of recovery. The plankton biomass was very low due to the poor nutrient content, and larvae of− 167 −

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benthic animals were only 1.5 % of all plankton. From the above, it will take time for new benthic
animals to occupy the area and gain a foothold in the marine ecosystem around Nishinoshima. It is
possible that the benthic fauna will remain in the deep sea near the island after the eruption in July
2020. If benthic animal larvae move in from the deep sea, the primary succession will advance faster.
In this study, the primary succession status of the marine ecosystem around Nishinoshima wasconfirmed. Future studies should monitor the primary succession around oceanic island
Nishinoshima regularly, concerning the deep sea, the current around it, and the breeding season ofeach species.
Key words
Bonin Islands㸪Bryozoa㸪Hydrozoa㸪Primary succession㸪Volcanic eruption

− 168 −