Sudden crash of a local population of the endangered bagrid catfish Pseudobagrus ichikawai
The bagrid catfish Pseudobagrus ichikawai is an endangered freshwater fish (EN in the Red Data Book of Japan; Ministry of the Environment 2003) and distributed only in a narrow region of central Honshu, Japan. The catfish inhabits the middle reaches of rivers in well-protected environments and thus is particularly susceptible to any introduced water pollution or human-made changes to habitat structure (Watanabe 1997; Kobayakawa 2003). Several studies have addressed the conservation (e.g., Watanabe and Mori 1998; Mori and Watanabe 1999) and basic ecology (e.g., Watanabe 1994, 2008; Tashiro et al. 2005) of this species. A long-term (>ten-year) study conducted in a tributary of the Nagara River system, Gifu Prefecture, indicated that the population of P. ichikawai fluctuates greatly, primarily because of changes in recruitment among years, likely to be because of regional or climatic factors such as rain-induced floods (Watanabe and Ichiyanagi 2006, unpublished data). Conservation...
KeywordsLower Section Habitat Unit Population Crash Gifu Prefecture Plecoglossus Altivelis
I thank the local fishermen’s cooperatives, S. Andoh, H. Murase, and the late S. Watanabe and his family for their help during the field study, and H. Ichiyanagi, S. Mori, K. Ohara, T. Tokuhara, N. Nakanishi, Y. Harada, T. Kikko, S. Ota, and A. Sakai for providing information.
- Inoe K (2000) Coldwater disease of ayu (Plecoglossus altivelis). Aquabiology 22:35–38Google Scholar
- Kobayakawa M (2003) Pseudobagrus ichikawai. In: Ministry of the Environment (ed) Threatened wildlife of Japan, red data book, 2nd edn, vol 4. Pisces, brackish and freshwater fishes. Japan Wildlife Research Center, Tokyo, pp 110–111Google Scholar
- Ministry of the Environment (2003) Threatened wildlife of Japan, red data book, 2nd edn, vol 4. Pisces, brackish and freshwater fishes. Japan Wildlife Research Center, TokyoGoogle Scholar
- Mori S, Watanabe K (1999) Habitat use of Pseudobagrus ichikawai after ground sill construction. In: Mori S (ed) Conservation ecology of freshwater organisms (Tansui seibutsu no hozen seitaigaku). Shinzansha-Sci-Tech, Tokyo, pp 105–114Google Scholar
- Tashiro T, Sagawa S, Kayaba Y, Saiki M, Hasegawa K (2005) Physical habitat of endangered catfish Pseudobagrus ichikawai (Siluriformes: Bagridae) in lower order streams. Advances in River Engineering 11:471–476Google Scholar
- Watanabe K (1994) Growth, maturity and population structure of the bagrid catfish, Pseudobagrus ichikawai, in the Tagiri River, Mie Prefecture, Japan. Jpn J Ichthyol 41:15–22Google Scholar
- Watanabe K (1997) Pseudobagrus ichikawai. In: Nagata Y, Hosoya K (eds) Circumstances in endangered Japanese freshwater fishes and their protection. Midori Shobo, Tokyo, pp 122–132Google Scholar
- Watanabe K, Ichiyanagi H (2006) Long-term population dynamics and population viability analysis of the endangered bagrid catfish Pseudobagrus ichikawai. In: Ecological Society of Japan (ed) Abstracts of the 53rd Annual Meeting of the Ecological Society of Japan, Kyoto, p 338Google Scholar
- Watanabe K, Ito S (1999) Population size and distribution of Pseudobagrus ichikawai, an endangered bagrid catfish, in the Kawaura River. Jpn J Ichthyol 46:15–30Google Scholar
- Watanabe K, Mori S (1998) Change in habitat use of Pseudobagrus ichikawai between before and after re-building a bridge. In: Mori S (ed) Freshwater environments from view of fishes (Sakana kara mita mizu kankyo). Shinzansha-Sci-Tech, Tokyo, pp 161–176Google Scholar