Opsariichthys uncirostris uncirostris

(Japanese Journal of Conservation Ecology) 19 : 151-158 (2014) 調査報告 Opsariichthys uncirostris uncirostris * A detailed assessment of the distribution of Opsariichthys uncirostris uncirostris along the shoreline of Lake Biwa Akio Imamura* Osaka Museum of Natural History II 1 45 km 28 175 58 / / / GLMM / 4 PERMANOVA GLMM PERMANOVA PERMANOVA Abstract: I investigated the distribution of the piscivorous fish Opsariichthys uncirostris uncirostris (classified as vulnerable [VU]) along 45 km of the southwest shoreline of Lake Biwa, central Japan. The species was observed at 58 of 175 sites studied. Although it mainly occurred north of Otsu City, i.e., the Shiga District, I also found the species in the city s densely populated southern districts. I used generalized linear mixed model (GLMM) analysis to examine the probability of adult and immature O. u. uncirostris occurrence (binary data) in terms of several explanatory variables: lake substrate type (sand, gravel, and other), watercourse shape (surface stream, subterranean stream, dried-up stream, and shore), the presence of reeds, embankments, and/or trees along the watercourse, and the season (spring, summer, autumn, and winter), with site as a random effect. The GLMM indicated a positive effect of sandy substrate on O. u. uncirostris presence. I used permutational analyses of variance (PERMANOVAs) to examine the presence/absence of adult and immature fish in terms of the same explanatory variables as the GLMM, with the exception of season. This analysis also showed that the substrate significantly affected O. u. uncirostris occurrence. Thus, sandy substrates should be protected to promote O. u. uncirostris inhabitance. Keywords: generalized linear mixed model, lake bottom, permutational multivariate analysis of variance, piscivorous fish, watercourse junction * 070-8621 9 Present Address: Hokkaido University of Education, Asahikawa Campus, Hokumon-cho 9, Asahikawa, Hokkaido 070-8621, Japan e-mail: ginryou715@yahoo.co.jp 2013 9 17 2014 8 4 151

Opsariichtys uncirostris uncirostris 2013 2013 FishBase.org http://www.fishbase.org/ 2013 11 13 ex-danioninae O. u. bidens O. u. amurensis 2012 2013 I HP http://www.erc.pref.fukui.jp/gbank/rdb/rdbdata/ fis000.html 2013 11 9 1993 2009 4 16 http://www.fukuishimbun.co.jp/modules/others/index. php?id=32&pid=48 2013 11 9 1955 200 t 2010 35 t HP http://www.pref.shiga.lg.jp/g/suisan/toukei/files/ gyoshu-gyokaku23.pdf 2013 11 9 II VU HP http://www. biodic.go.jp/rdb/rl2012/redlist2012_tansuigyorui.csv 2013 7 3 2010 5 2011 2010 1/1000 Micropterus salmoides 2011 230 km 118 400 500 2003 Kiffney et al. 2006 N P Ohsawa et al. 2010 調査の概要 2012 3 2013 3 45 km 133 28 42 175 1 2 139 1 2.1 1 31 調査方法 2009 40 m 152

90 1 30 60 解析 R3.1.0 for Mac OSX R core team 2013 http://www. R-project.org/ 2014 6 28 maptools http://nlftp.mlit.go.jp/ksj/ 2013 11 25 GoogleMap / GLMM glmmml / 5 vegan / 2 2 4 permutational multivariate analysis of variance PERMANOVA / / / 5 permutation 2011 5000 1 175 104 19 10 42 125 17 33 86 89 106 69 34 141 175 58 9 7 42 117 1 2 <http://yahoo.jp/ box/huwwpl> 100 m 2A-D 2D 2I-K 2K 5 GLMM 1 5 / PERMANOVA 5 2 153

1 2A-2K 2A-2K 2 5 km Fig. 1. Map of the research area in southwest Lake Biwa. Detailed maps are given in Figure 2, and letters 2A-2K correspond to each panel in Figure 2. Bar: 5 km; : Otsu City center. 5 7 / 8 11 12 / PERMANOVA GLMM PERMANOVA R 2 = 0.029 117 GLMM > > 2010 2011 2009 154

2 / 1 km A B C D E F Fig. 2. Detailed maps of the research sites, which are aligned north to south along the overall research area. The presence/absence of Opsariichthys uncirostris uncirostris and the shape of the watercourse are plotted for each research site. Bar: 1 km. Letters indicate districts of Otsu City: (A) Northern Hourai; (B) Southern Hourai; (C) Wani; (D) Mano; (E) Katata; (F) Ogoto. : surface stream with O. u. uncirostris; : surface stream without O. u. uncirostris; : subterranean stream with O. u. uncirostris; : subterranean stream without O. u. uncirostris; : dried-up stream with O. u. uncirostris; : dried-up stream without O. u. uncirostris; : shore with O. u. uncirostris, : shore without O. u. uncirostris. 155

2 G H I J K Fig. 2 (continued). (G) Northern Sakamoto; (H) Southern Sakamoto; (I) Karasaki; (J) Central Otsu; and (K) Seta. : surface stream with O. u. uncirostris; : surface stream without O. u. uncirostris; : subterranean stream with O. u. uncirostris; : subterranean stream without O. u. uncirostris; : dried-up stream with O. u. uncirostris; : dried-up stream without O. u. uncirostris; : shore with O. u. uncirostris, : shore without O. u. uncirostris. 156

1 / GLMM Table 1. Summary of GLMM for the effects of environmental variables on occurrence of Opsariichthys uncirostris uncirostris. Estimate Std. Error z value Pr(> z ) AIC = 239 Intercept a -3.6095 1.5196-2.375 0.0175* Lake bottom: gravel 1.4264 1.3742 1.038 0.2990 Lake bottom: sand 2.9332 1.3468 2.178 0.0294* Watercourse: open -0.1297 0.6949-0.187 0.8520 Watercourse: underground 0.6082 0.9977 0.610 0.5420 Watercourse: dried-up -2.4251 1.6857-1.439 0.1500 Presence of reeds 0.5787 0.6234 0.928 0.3530 Embankment 0.1872 0.7227-0.259 0.7960 Presence of trees on the watercourse side 0.4428 0.7122 0.622 0.5340 Season: spring -0.8012 0.7803-1.027 0.3050 Season: summer -0.0788 0.8972-0.088 0.9300 Season: winter -1.1813 1.2628-0.935 0.3500 a: base of lake bottom is paved and other ; base of watercourse is shore ; bottom of season is autumn *: p< 0.05 2 / PERMANOVA Table 2. Results of PERMANOVA for the effects of environmental variables on occurrence of the adult and immature fish of Opsariichthys uncirostris uncirostris. Df Sums of squares Mean squares F Model R 2 Pr(>F) Bottom of lake 2 1.472 0.7361 2.610 0.02905 0.04479* Watercourse shape 3 1.060 0.3534 1.253 0.02093 0.27335 Presence of reeds 1 0.424 0.4235 1.502 0.00836 0.21396 Embankment 1 0.886 0.8863 3.144 0.01749 0.05099 Presence of trees on the watercourse side 1 0.031 0.0307 0.109 0.00061 0.88742 Residuals 166 46.801 0.2819 0.92357 Total 174 50.674 1 *: p< 0.05 PERMANOVA R 2 = 0.020 GLMM P = 0.15 GLMM > > > 19 11 104 http://www.water.go.jp/kansai/niu/html/ kawamoyou/kawamoyou.html 2013 7 24 100 m 2009 2011 157

19 11 10 2 2 5 1 GoogleMap 25 4 2010 2011 175 16 51 2010 (2011) R,,. 61:3-20. (2013) Cyprinidae. ( ) 3. pp 308-327.,. (2011).,. Kiffney PM, Greene CM, Hall JE, Davies JR (2006) Tributary streams create spatial discontinuities in habitat, biological productivity, and diversity in mainstem rivers. Canadian Journal of Fisheries and Aquatic Sciences 63:2518-2530. (2003). ( ). pp 231-234.,. (2009).. pp 7-60.,.. (2009).,. Ohsawa T, Mitsuhashi H, Ushimaru A (2010) River confluences enhance riparian plant species diversity. Plant Ecology 209:95-108. (2012). 17:19-29. (2010).,. (2011) MAP.,. 158