A Japanese eel Anguilla japonica was collected off Kozushima Island, one of the volcanic Izu Islands in Japan. The external morphology corresponded to a silvering stage (Silvering Index: S1) with a melanized body coloration of the head, and the tip of the lower jaw to the anus. However, the value of the gonado-somatic index of the female eel was low, and the oocytes were not matured (peri-nucleolus stage). Otolith analyses indicated that the individual had exclusively inhabited the sea for five years without entering freshwater. This record is the first collection of silver-phased Japanese eel in the Kuroshio region, which could be on the spawning migration route of the species, although it was not determined if the eel was settling around the Izu Islands or migrating to the spawning ground.
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Ambe D, Imawaki S, Uchida H, Ichikawa K (2004) Estimating the Kuroshio axis south of Japan using combination of satellite altimetry and drifting buoys. J Oceanogr 60:375–382
Chen S-C, Chang C-R, Han Y-S (2018) Seaward migration routes of indigenous eels, Anguilla japonica, A. marmorata, and A. bicolor pacifica, via satellite tags. Zool Stud 57:21
Chow S, Kurogi H, Mochioka N, Kaji S, Okazaki M, Tsukamoto K (2009) Discovery of mature freshwater eels in the open ocean. Fish Sci 75:257–259
Higuchi T, Watanabe S, Manabe R, Kaku T, Okamura A, Yamada Y, Miller MJ, Tsukamoto K (2018) Tracking Anguilla japonica silver eels along the West Marina Ridge using pop-up archival transmitting tags. Zool Stud 57: 24
Kawabe M (1995) Variation of current path, velocity, and volume transport of the Kuroshio in relation with the large meander. J Phys Oceanogr 25:3103–3117
Kuroki M, Righton D, Walker AM (2014) The importance of Anguillids: a cultural and historical perspective introducing papers from the World Fisheries Congress. Ecol Freshw Fish 23:2–6
Manabe R, Aoyama J, Watanabe K, Kawai M, Miller MJ, Tsukamoto K (2011) First observations of the oceanic migration of Japanese eel, from pop-up archival transmitting tags. Mar Ecol Prog Ser 437:229–240
Okamura A, Yamada Y, Yokouchi K, Horie N, Utho T, Mikawa N, Tanaka S, Tsukamoto K (2007) A silvering index for the Japanese eel Anguilla japonica. Environ Biol Fish 80:77–89
Otake T, Amano Y, Shirai K, Mochioka N, Takahashi T, Chow S, Kurogi H, Dou S, Yamaguchi A, Tsukamoto K (2019) Evaluation from otolith Sr stable isotope ratios of possible juvenile growth areas of Japanese eels collected from the West Mariana Ridge spawning area. Fish Sci 85:483–493
Otsuka K (1985) Characteristics of the Kuroshio in the vicinity of the Izu Ridge. J Oceanogr Soc Japan 41:441–451
Shinoda A, Aoyama J, Miller MJ, Otake T, Mochioka N, Watanabe S, Minegishi Y, Kuroki M, Yoshinaga T, Yokouchi K, Fukuda N, Sudo R, Hagihara S, Zenimoto K, Suzuki Y, Oya M, Inagaki T, Kimura S, Fukui A, Lee TW, Tsukamoto K (2011) Evaluation of the larval distribution and migration of the Japanese eel in the western North Pacific. Rev Fish Biol Fisher 21:591–611
Sudo R, Suetake H, Suzuki Y, Utoh T, Tanaka S, Aoyama J, Tsukamoto K (2011) Dynamics of reproductive hormones during downstream migration in Japanese eels, Anguilla japonica. Zool Sci 28:180–188
Tsukamoto K (1992) Discovery of the spawning area for the Japanese eel. Nature 356:789–791
Tsukamoto K (2006) Spawning of eels near a seamount. Nature 439:929
Tsukamoto K (2009) Oceanic migration and spawning of anguillid eels. J Fish Biol 74:1833–1852
Tsukamoto K, Arai T (2001) Facultative catadromy of the eel Anguilla japonica between freshwater and seawater habitats. Mar Ecol Prog Ser 220:265–276
Tsukamoto K, Nakai I, Tesch FW (1998) Do all freshwater eels migrate? Nature 396:635–636
Tsukamoto K, Chow S, Otake T, Kurogi H, Mochioka N, Miller MJ, Aoyama J, Kimura S, Watanabe S, Yoshinaga T, Shinoda A, Kuroki M, Oya M, Watanabe T, Hata K, Ijiri S, Kazeto Y, Nomura K, Tanaka H (2011) Oceanic spawning ecology of freshwater eels in the western North Pacific. Nat Commun 2:179
Tzeng WN, Wang CH, Wickström H, Reizenstein M (2000) Occurrence of the semi-catadromous European eel Anguilla anguilla in the Baltic Sea. Mar Biol 137:93–98
Utoh T, Mikawa N, Okamura A, Yamada Y, Tanaka S, Horie N, Akazawa A, Oka HP (2004) Ovarian morphology of the Japanese eel in Mikawa Bay. J Fish Biol 64:502–513
Watanabe S, Minegishi Y, Yoshinaga T, Aoyama J, Tsukamoto K (2004) A quick method for species identification of Japanese eel (Anguilla japonica) using real-time PCR: an onboard application for use during sampling surveys. Mar Biotechnol 6:566−574
Yokouchi K, Fukuda N, Miller MJ, Aoyama J, Daverat F, Tsukamoto K (2012) Influences of early habitat use on the migratory plasticity and demography of Japanese eels in central Japan. Estuar Coast Shelf Sci 107:132–140
We are grateful to Kazuto Ando and Ichiro Komazawa of Tokyo Metropolitan Islands Area Research and Development Center of Agriculture, Forestry and Fisheries, and to Ryosuke Matsue and Kazutaka Hamakawa for providing the eel specimen. We thank Toyoji Kaneko for the technical support of the histological analysis.
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Kuroki, M., Mikawa, N., Mizuta, F. et al. Sea resident Japanese eel collected from Kozushima Island, Japan. Ichthyol Res (2020). https://doi.org/10.1007/s10228-019-00731-8
- Anguilla japonica
- Izu Islands
- Silver eel
- Spawning migration