Cambaroides Japonicus De Haan

CRUSTACEAN RESEARCH, SPECIAL NUMBER 7: 133–140, 2012 132

Nakata, K., & Goshima, s., 2006. AsymmetryT. GoTo & T. Kawaigland development in the crayfish, Cambarus. in mutual predation between the endangered Biological Bulletin, 103, 242–258. Habitat characteristics of small creeks inhabiting Japanese Japanese native crayfish Cambaroides japonicus suko, T., 1953. studies on the development of the endemic crayfishes Cambaroides( japonicus De Haan) in and the North American invasive native crayfish crayfish I. The development of secondary sex Pacifastacus leniusculus: a possible reason for characters in appendages. Science Reports of northern Japan species replacement. Journal of Crustacean saitama University, series B, 1: 77–96. Biology, 26: 134–140. suko, T., 1954. studies on the development of Nakatani, I., 1999. An albino of the crayfish the crayfish II. The development of egg–cell Procambarus clarkii (Decapoda: Cambaridae) before fertilization. Science Reports of Saitama Masanori Nunokawa, Kazunori Tanaka and Kousuke Ikeda and its offspring. Journal of Crustacean Biology, University, series B. 1: 165–175. 19: 380–383. suko, T., 1961. studies on the development of the Nakatani, I., 2000. reciprocal transplantation of crayfish VII. The hatching and the hatched Abstract.—As an engineer of physical processes et al., 2008) and serve as critical transporters leg tissue between albino and wild crayfish young. Science Reports of Saitama University, instead of biotic processes, Cambaroides japonicus Procambarus clarkii (Decapoda: Cambaridae). of energy through trophic webs. Research in series B, 5: 37–42. is very important in mountain stream ecosystems. Journal of Crustacean Biology, 20: 453–459. Otago, New Zealand, showed that crayfish young, C. M., 1937. On the nature and permeability Additionally, the small stream habitats of the (Paranephrops zealandicus) have a lower Nakata, K., Hayashi, N., Ozaki, M., Ohtaka, A., of chitin. I–the chitin lining the foregut of species continue to disappear. It is very important ability to decompose litter compared to other & Miwa, J., 2010. First record of the North decapod crustacean and the function of the to determine environmental conditions in American invasive crayfish Pacifastacus macroinvertebrates, whereas the dominant tegumental glands. proceeding of royal society, these small streams to conserve and manage C. crayfish, by biomass, is more important as a leniusculus from the Kanto region, Tone River series B, 3: 298–329. basin, central Japan: a range expansion to a warm japonicus habitats. The aims of this study were decomposer than other macroinvertebrates water area. plankton and Benthos research, 5: to document the environmental characteristics (Usio & Townsend, 2001). 165–168. of small creek habitats using physical data. Addresses: (TG) Mie University, Faculty Principle components analysis (PCA) was used On the other hand, crayfish act as piemental, D., Zuniga, r., & Morrison, D., 2005. of Education, Science Education, Tsu, Mie to examine patterns in the physical structure ecosystem engineers (Jones et al., 1994), Update on the environmental and economic 514–8507, Japan, (TK) Wakkanai Fisheries influencing fine sediment mobilization costs associated with alien–invasive species in of small creeks and streams. Differences in the United states. ecology of economic, 52: research Institute, Wakkanai, 097–0001 physical variables between habitat types were (Statzner et al., 2003; Statzner et al., 2000), 273–288. Hokkaido, Japan; examined. The second axis from the PCA, which and can affect detrital processing rates and the distribution of particulate organic matter stephens, G. C., 1952. The control of cement email: (TG) @, (TK) @ was positively correlated with flow velocity and substrate coarseness, indicated that these habitats that is used by other macroinvertebrates are characterized by erosional and depositional (Creed & Reed, 2004). gradients. Stream habitats were significantly C. japonicus generally inhabits creeks deeper and faster than habitats in small creeks. and lakes with low temperatures. Although Our data also show that C. japonicus inhabits numerous C. japonicus are found in lakes in small creeks with fine substrate and without Hokkaido, Kawai (1994) reported that many boulders. lentic habitats were notably important in recent decades. Furthermore, small stream INTRODUCTION habitats continue to disappear (Kawai, 1996; Kawai et al., 2009). It is difficult to identify Crayfish serve as shredders (Merritt streams that are C. japonicus habitats & Cummins, 1996; Nunokawa, 2009), because they are small and lack pool–riffle transporting energy from the leaves of sequences. It is very important to determine riparian vegetation to higher trophic the environmental characteristics of C. levels. Shredders reduce the size of coarse japonicus habitats in these small streams particulate organic matter to fine particulate for their conservation and management. organic matter. Macroinvertebrates then Usio (2007) and Ishiyama et al. (2012) consume the fine particulate organic matter investigated environmental characteristics fragments as food resources, incorporating of C. japonicus habitats from headwaters the organic matter into the local food web to midstream areas but did not focus on (Abe & Nunokawa, 2005). Japanese crayfish small streams without pool–riffle sequences, (Cambaroides japonicus) dominate the which are important for C. japonicus. macroinvertebrate biomass and production Furthermore, flow fluctuations in most small in some Northern Japanese streams (Yamada streams originating from springs do not vary CHARACTERISTICS OF CRAYFISH CREEKS IN JAPAN 135 134 134 ET AL. M. NuNokawa throughout the year. C. japonicus are easily habitats were defined by having channel Table 1. Summary of environmental characteristics in lentic and lotic habitats of Japanese crayfish (Cambaroides swept away by high water velocities (from an morphologies. Both small creek and stream japonicus) assessment of velocities in artificial burrows: habitats had riparian vegetation, low water Locationa Vegetation Habitat Stream Wetted Depth Substrate Water Sources Nakata et al., 2003b; Kawai, 2007) and they temperatures and substrates with leaf litter type lengthb width (m) (cm) typec temperature are subject to flow disturbances. Therefore, and coarse woody debris. Deciduous broad– (km) (°C) C. japonicus populations have probably been leaved trees and grasses dominated the Abashiri broad–leaf stream 6 2 15 20–30, 100–300 13.6 1 maintained in small streams. Considering the riparian vegetation at both habitat types. The Kushiro broad–leaf stream – 0.5–1 5 pebble, sand, boulder – 1 mechanisms for population maintenance, it is mean water temperatures for each habitat Yubari broad–leaf stream – 0.3 < 1 pebble, 100 – 1 very important to identify the characteristics type were 14.9 and 15.7°C, respectively. Lake Komadome – lake 0.04 km2 – 500 coarse sand (> 4.0 ) 0.7–21.4 2 of small stream habitats. Field measurements were conducted during Lake Shikaribetus – lake – – 100–300 – 11.7–13.5 3 The aims of this study were to document seasons when C. japonicus were active and Lake A in Shiribeshi broad–leaf lake – – 0–50 sand, pebble, boulder 21.5– 4 the environmental characteristics of C. there were low flow rates. Lake B in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 17.2 4 japonicus habitats in Hokkaido and Aomori Lake C in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 20.5– 4 prefectures, and to clarify the environmental Variables used in statistical analyses Lake D in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 15.2 4 variables of small stream habitats using Maximum wetted width was the Lake E in Shiribeshi conifer, broad–leaf lake – – 0–50 sand, pebble, boulder 5.2 4 physical data from 66 sites in Hokkaido maximum width within which C. japonicus Lake F in Shiribeshi conifer, broad–leaf lake – – 0–50 sand, pebble, boulder 5.2 4 (including 47 streams and 19 small creek occurred. Maximum depth in the habitats was Otaru broad–leaf stream – > 5 > 25 64–16 – 5 habitats). estimated to be 1 cm when actual depth was Otaru – stream – 3 Jan 15 May 256–64 – 5 less than 1 cm. Similarly, flow velocity was Otaru – stream – < 1 < 5 medium sand – 5 estimated to be 5 cm/s when the measured Bibai broad–leaf stream – 0.7 4.7 sand, gravel, cobble 17.2 6 MATerIAlS AnD MeTHODS velocity was less than 5 cm/s. The substrate Ashoro conifer lake 250 m2 – – medium sand 12 7 types within each habitat were classified Erimo broad–leaf lake 300 m2 – – boulder 15.9 7 C. japonicus Habitats and coded as 1) silt (particle size < 0.09 Okushiri broad–leaf stream 0.1 1 4 coarse sand 17.4 7 We identified 41 C. japonicus habitats in mm), 2) fine sand (0.09–0.1 mm), 3) coarse Kamikawa broad–leaf stream 0.25 0.5 < 1 coarse sand 10.8 7 Hokkaido and Aomori prefectures based on sand (0.1–2.0 mm), 4) gravel (2–10 mm), 5) Atsuta broad–leaf stream 1 1 5 coarse sand 15.6 7 the results of a previous investigation (Table pebble (10–20 mm) and 6) cobble (>20 mm). Kyouwa broad–leaf lake 62 m2 – – silt 9.8 7 1). The habitat characteristics examined The dominant substrate code was used to Kushiro broad–leaf stream 0.3 1 10 coarse sand 12.1 7 included vegetation, habitat type, stream express substrate coarseness (see Bain et al., Sapporo broad–leaf stream 0.1 3 3 coarse sand 15 7 length (km), lake surface area (m2 or km2), 1985; Ikeda & Nunokawa, 2011). The mean Shiraoi conifer stream 0.1 2 1 coarse sand 12.1 7 width (m), depth (cm), substrate type or of these coded values was used to express Takikawa broad–leaf stream 0.02 0.4 < 1 sand 11.6 7 Tsubetsu broad–leaf stream 0.03 0.3 1 coarse sand 12.1 7 grain size (mm), and water temperature substrate coarseness when the substrate 2 (°C). Specific locations are not provided included more than two dominant substrate Teshikaga broad–leaf lake 0.08 km – – coarse sand 17 7 in the interests of conserving C. japonicus types. Nakashibetsu broad–leaf stream 0.02 0.5 1 coarse sand 18.9 7 populations. Mashike broad–leaf stream 0.1 0.5 5 coarse sand 10.7 7 Statistical analyses Yakumo conifer stream 0.05 0.8 3 coarse sand 18.7 7 Habitat variables We used principle components analysis Yoichi broad–leaf stream 0.2 1 5 coarse sand 15.4 7 Environmental conditions were measured (PCA) ordination techniques to examine Rebun broad–leaf stream 0.3 0.5 5 coarse sand 8.5 7 in 66 stream habitats in Hokkaido. These patterns in the physical structure of small Ebetsu broad–leaf stream – 0.3 1 coarse sand, fine sand 14.2 8 Ebetsu broad–leaf stream – 0.3 1 coarse sand, fine sand 16.5 8 streams were near 11 cities (Taisei, Assabu, creek and stream habitats. Maximum wetted Ebetsu broad–leaf stream – 0.5 4 coarse and fine sand 6.2 8 Setana, Otaru, Ebetsu, Rumoi, Obira, width, maximum depth, flow velocity and Ebetsu broad–leaf stream – 0.2 1 coarse sand, pebble 13.8 8 Samani, Urahoro, Rausu, and Abashiri) substrate coarseness were used as variables in the PCA. The relationships between Atsuta, Hamamasu broad–leaf stream 0.1–0.15 1 1 5–10, 300 – 9 on the Hokkaido main island and other Shikaoi lake – – 500 – – 10 principle component axes one and two and small islands (including Rebun, Teuri, Sapporo broad–leaf stream 0.1 1.5 – 0.25–0.50, 0.125–0.25 15 11 Yagishiri, and Okushiri Island). The presence the physical variables were examined using Aomori Shichinohe – stream – 0.5–1.0 1 – 16.2 12 of C. japonicus in all of the examined Pearson’s correlation analysis. In the above Otofuke – lake 49 m2 – 200 silt 14 13 streams was verified by searching under analyses, variables were log10–transformed boulders. Research sites included small to achieve standardization and to improve Note: 1–Kawai et al. (2006), 2–Kawai (1993), 3–Nakata et al. (2003a), 4–Kawai et al. (2004b), 5–Japanese Crayfish streams (hereafter, “small creeks”) and normality, as required. Research Group (2005), 6–Yamada et al. (2008), 7–Kawai (1994), 8–Kawai et al. (2004a), 9–Kawai et al. (2001), 10– stream habitats. Small creek habitats were Kawai (1995), 11–Kawai (1992), 12–Kawai & Nakata (2001), 13–Kawai et al. (2000). a: Detailed locations for C. Differences in physical variables japonicus populations are not provided to protect their habitats. b: Areas are indicated for lakes and swamps. c: Substrate characterized by having extremely low flow (maximum wetted width, maximum depth, categories are as follows: boulder (diameter > 256 mm), cobble (20 mm to 256 mm), pebble (10 mm to 20 mm), gravel (2 rates and no channel morphologies that flow velocity and substrate coarseness) mm to 10 mm), coarse sand (0.1 mm to 2.0 mm), fine sand (0.09 mm to 0.1 mm) and silt (< 0.09 mm). Primary grain size included pool–riffle sequences, while stream between habitat types (small creeks and (mm) or expressions of references are described if it was difficult to select a specific category. – indicates no data. CHARACTERISTICS OF CRAYFISH CREEKS IN JAPAN 135 134 ET AL. 135 M. NuNokawa throughout the year. C. japonicus are easily habitats were defined by having channel Table 1. Summary of environmental characteristics in lentic and lotic habitats of Japanese crayfish (Cambaroides swept away by high water velocities (from an morphologies. Both small creek and stream japonicus) assessment of velocities in artificial burrows: habitats had riparian vegetation, low water Locationa Vegetation Habitat Stream Wetted Depth Substrate Water Sources Nakata et al., 2003b; Kawai, 2007) and they temperatures and substrates with leaf litter type lengthb width (m) (cm) typec temperature are subject to flow disturbances. Therefore, and coarse woody debris. Deciduous broad– (km) (°C) C. japonicus populations have probably been leaved trees and grasses dominated the Abashiri broad–leaf stream 6 2 15 20–30, 100–300 13.6 1 maintained in small streams. Considering the riparian vegetation at both habitat types. The Kushiro broad–leaf stream – 0.5–1 5 pebble, sand, boulder – 1 mechanisms for population maintenance, it is mean water temperatures for each habitat Yubari broad–leaf stream – 0.3 < 1 pebble, 100 – 1 very important to identify the characteristics type were 14.9 and 15.7°C, respectively. Lake Komadome – lake 0.04 km2 – 500 coarse sand (> 4.0 ) 0.7–21.4 2 of small stream habitats. Field measurements were conducted during Lake Shikaribetus – lake – – 100–300 – 11.7–13.5 3 The aims of this study were to document seasons when C. japonicus were active and Lake A in Shiribeshi broad–leaf lake – – 0–50 sand, pebble, boulder 21.5– 4 the environmental characteristics of C. there were low flow rates. Lake B in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 17.2 4 japonicus habitats in Hokkaido and Aomori Lake C in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 20.5– 4 prefectures, and to clarify the environmental Variables used in statistical analyses Lake D in Shiribeshi conifer, broad–leaf lake – – 0–50 silt, sand, boulder 15.2 4 variables of small stream habitats using Maximum wetted width was the Lake E in Shiribeshi conifer, broad–leaf lake – – 0–50 sand, pebble, boulder 5.2 4 physical data from 66 sites in Hokkaido maximum width within which C. japonicus Lake F in Shiribeshi conifer, broad–leaf lake – – 0–50 sand, pebble, boulder 5.2 4 (including 47 streams and 19 small creek occurred. Maximum depth in the habitats was Otaru broad–leaf stream – > 5 > 25 64–16 – 5 habitats). estimated to be 1 cm when actual depth was Otaru – stream – 3 Jan 15 May 256–64 – 5 less than 1 cm. Similarly, flow velocity was Otaru – stream – < 1 < 5 medium sand – 5 estimated to be 5 cm/s when the measured Bibai broad–leaf stream – 0.7 4.7 sand, gravel, cobble 17.2 6 MATerIAlS AnD MeTHODS velocity was less than 5 cm/s. The substrate Ashoro conifer lake 250 m2 – – medium sand 12 7 types within each habitat were classified Erimo broad–leaf lake 300 m2 – – boulder 15.9 7 C. japonicus Habitats and coded as 1) silt (particle size < 0.09 Okushiri broad–leaf stream 0.1 1 4 coarse sand 17.4 7 We identified 41 C. japonicus habitats in mm), 2) fine sand (0.09–0.1 mm), 3) coarse Kamikawa broad–leaf stream 0.25 0.5 < 1 coarse sand 10.8 7 Hokkaido and Aomori prefectures based on sand (0.1–2.0 mm), 4) gravel (2–10 mm), 5) Atsuta broad–leaf stream 1 1 5 coarse sand 15.6 7 the results of a previous investigation (Table pebble (10–20 mm) and 6) cobble (>20 mm). Kyouwa broad–leaf lake 62 m2 – – silt 9.8 7 1). The habitat characteristics examined The dominant substrate code was used to Kushiro broad–leaf stream 0.3 1 10 coarse sand 12.1 7 included vegetation, habitat type, stream express substrate coarseness (see Bain et al., Sapporo broad–leaf stream 0.1 3 3 coarse sand 15 7 length (km), lake surface area (m2 or km2), 1985; Ikeda & Nunokawa, 2011). The mean Shiraoi conifer stream 0.1 2 1 coarse sand 12.1 7 width (m), depth (cm), substrate type or of these coded values was used to express Takikawa broad–leaf stream 0.02 0.4 < 1 sand 11.6 7 Tsubetsu broad–leaf stream 0.03 0.3 1 coarse sand 12.1 7 grain size (mm), and water temperature substrate coarseness when the substrate 2 (°C). Specific locations are not provided included more than two dominant substrate Teshikaga broad–leaf lake 0.08 km – – coarse sand 17 7 in the interests of conserving C. japonicus types. Nakashibetsu broad–leaf stream 0.02 0.5 1 coarse sand 18.9 7 populations. Mashike broad–leaf stream 0.1 0.5 5 coarse sand 10.7 7 Statistical analyses Yakumo conifer stream 0.05 0.8 3 coarse sand 18.7 7 Habitat variables We used principle components analysis Yoichi broad–leaf stream 0.2 1 5 coarse sand 15.4 7 Environmental conditions were measured (PCA) ordination techniques to examine Rebun broad–leaf stream 0.3 0.5 5 coarse sand 8.5 7 in 66 stream habitats in Hokkaido. These patterns in the physical structure of small Ebetsu broad–leaf stream – 0.3 1 coarse sand, fine sand 14.2 8 Ebetsu broad–leaf stream – 0.3 1 coarse sand, fine sand 16.5 8 streams were near 11 cities (Taisei, Assabu, creek and stream habitats. Maximum wetted Ebetsu broad–leaf stream – 0.5 4 coarse and fine sand 6.2 8 Setana, Otaru, Ebetsu, Rumoi, Obira, width, maximum depth, flow velocity and Ebetsu broad–leaf stream – 0.2 1 coarse sand, pebble 13.8 8 Samani, Urahoro, Rausu, and Abashiri) substrate coarseness were used as variables in the PCA. The relationships between Atsuta, Hamamasu broad–leaf stream 0.1–0.15 1 1 5–10, 300 – 9 on the Hokkaido main island and other Shikaoi lake – – 500 – – 10 principle component axes one and two and small islands (including Rebun, Teuri, Sapporo broad–leaf stream 0.1 1.5 – 0.25–0.50, 0.125–0.25 15 11 Yagishiri, and Okushiri Island). The presence the physical variables were examined using Aomori Shichinohe – stream – 0.5–1.0 1 – 16.2 12 of C. japonicus in all of the examined Pearson’s correlation analysis. In the above Otofuke – lake 49 m2 – 200 silt 14 13 streams was verified by searching under analyses, variables were log10–transformed boulders. Research sites included small to achieve standardization and to improve Note: 1–Kawai et al. (2006), 2–Kawai (1993), 3–Nakata et al. (2003a), 4–Kawai et al. (2004b), 5–Japanese Crayfish streams (hereafter, “small creeks”) and normality, as required. Research Group (2005), 6–Yamada et al. (2008), 7–Kawai (1994), 8–Kawai et al. (2004a), 9–Kawai et al. (2001), 10– stream habitats. Small creek habitats were Kawai (1995), 11–Kawai (1992), 12–Kawai & Nakata (2001), 13–Kawai et al. (2000). a: Detailed locations for C. Differences in physical variables japonicus populations are not provided to protect their habitats. b: Areas are indicated for lakes and swamps. c: Substrate characterized by having extremely low flow (maximum wetted width, maximum depth, categories are as follows: boulder (diameter > 256 mm), cobble (20 mm to 256 mm), pebble (10 mm to 20 mm), gravel (2 rates and no channel morphologies that flow velocity and substrate coarseness) mm to 10 mm), coarse sand (0.1 mm to 2.0 mm), fine sand (0.09 mm to 0.1 mm) and silt (< 0.09 mm). Primary grain size included pool–riffle sequences, while stream between habitat types (small creeks and (mm) or expressions of references are described if it was difficult to select a specific category. – indicates no data. CHARACTERISTICS OF CRAYFISH CREEKS IN JAPAN 137 136 136 ET AL. M. NuNokawa (A) (B) (C) (D)

sand). Water temperature ranged between 6.2 ss 3.0 3.0 12 4.0

120 s) and 18.9°C in streams and between 0.7 and ne m) m) se m/ (c 2.0 21.5°C in lakes and swamps. (c

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Principle components analysis with 4 tr 40 1.0 ve

sand). Water temperature ranged between 6.2 ss 3.0 3.0 12 4.0

120 s) and 18.9°C in streams and between 0.7 and ne m) m) se m/ (c 2.0 21.5°C in lakes and swamps. (c

(c 3.0 ar h h 80 2.0 8 co ty ty pt

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Principle components analysis with 4 tr 40 1.0 ve

-1.0 habitat variables extracted two important bs 1.0 mu mum ow Su xi xi -2.0 components (eigenvalues > 1.0). These two 0 0 Fl 0 0 Ma components explained more than 70% of the Ma Stream Creek SSttrreeaamm CCrreeeekkSt Strreeaamm CCrreeeekk SSttrreeaamm CCrreeeekk PC axis 1 total variation (Table 2) and separated small Fig 2. Means (±SE) for maximum width (A), maximum depth (B), flow velocity (C), and substrate coarseness Fig 1. Plot of PCA axes that describe the differences creek and stream habitats (Fig. 1). Most of in environmental variables among sites. Habitats in (D) in each habitat type. Stream = stream habitat, Creek = small creek habitat. There were significant differences different dimensions of the tributaries are represented the stream habitats were distributed in the between habitats in maximum depth and flow velocity (Mann-Whitney test, p < 0.01). by different symbols as follows: black circles, stream positive region of the second PCA axis, while habitats; dark gray triangles, small creek habitats. most of the small creek habitats had scores that were less than 0.0. Stream habitats was no significant difference in substrate japonicus presumably can find refuge from existed along an erosional gradient because coarseness between the two habitat types. high temperatures. flow velocity and substrate coarseness were streams) were examined using Mann– positively correlated with this dimension (r > Whitney U–tests (Mann & Whitney, 1947). Characteristics of each habitat type 0.60, Table 2). Most small creek habitats had DIsCUssION PCA differentiated between small creek We conducted all of the statistical analyses low scores on the first PCA axis, which was C. japonicus habitats consist of two types: and stream habitats using environmental using SPSS®12.0. positively correlated with maximum wetted streams and lakes or swamps (Table 1). C. variables. Flow velocity was lower in small width and maximum depth (r > 0.60, Table 2). japonicus is known to inhabit headwaters and creeks than in streams. Most wetted width Small creek habitats had depositional beds reSulTS lakes or swamps with clear freshwater (see and depth values were also lower in small and low flow rates. Miyake, 1982; Kawai, 2007). Most stream creeks, but some small creeks were wide and Environmental features of habitats habitats were small creeks without pool– deep. These trends generally corresponded Table 1 shows the characteristics of Differences in environmental variables be- to the results of a comparison of the four tween habitat types riffle sequences; they were less than 1 km C. japonicus habitats in Hokkaido and in length, had narrow wetted widths, were environmental variations between habitat According to the Mann–Whitney U– Aomori prefectures. C. japonicus habitats shallow, and had a fine substrate. According types (Fig. 2). test, there were significant differences in were generally characterized by cold water to previous research, coarse substrate acting Maximum wetted width, maximum maximum depth and flow velocity between and were surrounded by riparian forests as a shelter is important for C. japonicus depth, flow velocity and substrate coarseness habitat types. Small creek habitats were comprised of deciduous broad–leaved trees. populations (Usio, 2007) in headwater areas, were extracted by the principle component shallower and slower than streams (Fig. The habitats in this region were divided into but small creeks without coarse substrate analysis as significant factors. Small creek 2). Maximum wetted width in small creek two types: streams and lakes or swamps. were recognized here as C. japonicus habitats habitats were slower and shallower than habitats was narrower than in streams, but the There were many stream habitats shorter than (Table 1). stream habitats, but there was no significant 1 km long. They had narrow wetted widths difference was not significant because there Water temperature is the most important difference in wetted width between the (typically < 1.0 m) and were shallow (< 5 was considerable variation in wetted width limiting factor for C. japonicus survival. habitats (Fig. 2). cm, with one exception). Moreover, these in both habitat types (Fig. 2). Maximum Differences in water temperature were A qualitative standard that separated streams had a fine substrate (sand and coarse wetted width ranged from 30 to 187 cm in small creeks and from 15 to 400 cm in observed among streams, lakes and swamps streams and small creeks in our study was the stream habitats. In stream habitats, maximum (Table 1) because the different habitats were presence of a pool–riffle sequence. Stream wetted width was sometimes smaller than in examined in different seasons. The range of habitats had these sequences but small small creeks and could exceed 2.1 times the water temperature values differed among creek habitats did not. We could generally Table 2. PCA results for environmental variables streams, lakes and swamps. According observe pool–riffle sequences in streams with all 66 sites included. Coefficients of intraset maximum value observed in small creeks. correlations among the environmental variables and Maximum depth was significantly larger in to one report, C. japonicus cannot live in with gradients of 0.1 to 2% (1/1000–1/50). PCA axes are also shown. ** = p < 0.01. stream habitats than in small creeks (Fig. headwater habitats with water temperatures Streams with higher gradients (> 2%) PCA 1 PCA 2 2, p < 0.01). Mean depth in small creek greater than 19°C (Tanaka, 2011), but they have step–pools and cascades (Bisson et did in the stream habitats in this study. In al., 2006). Because high flow rates cause Eigenvalue 1.71 1.18 habitats was only 1.3 cm; creeks provided lakes or swamps, temperatures of 21.5°C vertical erosion of the stream bed in higher– % Variation explained 42.8 29.4 very shallow habitats. Small creeks had flow were recorded along shorelines. These gradient streams, it is difficult to create Maximum width 0.86** –0.21 velocities of 3.8 cm/s and were almost lentic values probably represent the maximum cross–section profiles in wide channels. The Maximum depth 0.88** 0.08 habitats; flow velocities in streams (10.2 cm/ temperatures experienced within a year in lack of a significant difference in wetted Flow velocity 0.40** 0.68** s) were 2.7 times greater than in small creeks, these habitats, but in lakes or swamps C. width between stream and small creek Substrate coarseness –0.2 0.82** but the velocity was still not high. There CHARACTERISTICS OF CRAYFISH CREEKS IN JAPAN 139 138 138 ET AL. M. NuNokawa(Iwaki Zoen), Y. Fuji (Kesen–numa Forestry Kawai, T., 1994. Distribution and habitat of the Cambaroides japonicus. Journal of Community habitats was likely because the stream Japanese crayfish Cambaroides japonicus Cooperative Research Center, Senshu University, habitats experienced such geomorphological Corporative), and N. Watanabe (Hokkaido in Hokkaido, Japan. Bulletin of the Higashi 4: 51–56 (in Japanese with English abstract). processes. University) for participating in our research Taisetsu Museum of Natural History, 16: 21–24 Mann, H. B., & Whitney, D. R., 1947. On a test of Small creeks had fine substrates (Fig. activities. We thank S. Ohira, T. Takishita, (in Japanese with English summary). whether one of two variables is stochastically 1). However, there were no significant H. Maezawa, K. Otani, and K. Usuda for Kawai, T., 1995. Refuge and fecundity of the larger than the other. Annals of Mathematical differences in mean substrate coarseness providing us with the opportunity to conduct Japanese crayfish, Cambaroides japonicus, in Statistics 18:50–60. a stream and a small lake, in Hokkaido, Japan. Miyake, S., 1982. Illustrated colored encyclopedia of between stream and small creek habitats. our research and for providing general research information. Bulletin of the Higashi Taisetsu Museum of Japanese macro–crustacean 1., 261pp, Hoikusha, Most small creek habitats were dominated Natural History, 17: 73–77 (in Japanese with Osaka (in Japanese). by coarse and fine sand substrates, but English summary). Merritt, R., & Cummins, K. W., 1996. An some creek habitats were dominated by Kawai, T., 1996. Distribution of the Japanese introduction to the aquatic insects of North LITeRATURe CITeD fine sand and silt, or fine sand and pebbles. crayfish, Cambaroides japonicus, in Hokkaido, America, 3rd (ed.), Kendall–Hunt, Dubuque. Creek habitats had a depositional trend in Abe, T., & Nunokwa, M., 2005. Food web analysis Japan and its loss of habitat in Eastern Hokkaido. Nakata, K., Kawai, T., & Goshima, S., 2003a. their sediments because these habitats had using stable isotopes in a forested stream in Memoirs of the Kushiro City Museum, 20: 5–12 Rediscovery of the Japanese crayfish spring. Journal of the Japanese Forest Society, (in Japanese with English abstract). Cambaroides japonicus in Lake Shikaribetsu, extremely shallow depths and low water 87: 13–19 (in Japanese with English abstract). Kawai, T., 2007. Habitat of Cambaroides japonicus. Hokkaido, Japan. The Bulletin of the Higashi velocities. Small creek habitats had greater Bain, M. B., Finn, J. T., & Booke, H. E., 1985. In natural history of crayfish–An introduction to Taisetsu Museum of Natural History, 25: 61–66 variation in substrate values than did streams. Quantifying stream substrate for habitat analysis Satokawa Gaku, Tokai University Press, Tokyo, (in Japanese with English summary). Therefore, substrate coarseness did not show studies. North American Journal of Fisheries 41–53 (in Japanese). Nakata, K., Hamano, T., Hayashi, K., & Kawai, T., any significant difference between habitats. Management, 5: 499–506. Kawai, T., Hori, S., Mizushima, M., & Nagasaka, 2003b. Water velocity in artificial habitats of Bisson, P. A., Montgomery, D. R., & Buffington, J. Y., 2004a. Distribution and present status of the Japanese crayfish Cambaroides japonicus. C. japonicus creates burrows, which M., 2006. Valley segments, stream reaches, and the Japanese crayfish (Cambaroides japonicus) Fisheries Science, 69: 343–347. are filled with subsurface water, allowing channel units. In: F. R. Hauer & G. A. Lamberti, population in the Nopporo Forest Park. The Nunokawa, M., 2009. Classification by feeding crayfish to survive in the burrows during the (eds.), “Methods in stream ecology, 2nd ed.”, Memoirs of the Historical Museum of Hokkaido, functional group. In Y., Takahashi, T. Iwaya, winter. There were no crayfish populations Aacademic Press. Burlington, 23–49. 43: 33–38 (in Japanese with English abstract). T. Oki, Y. Shimatani, K. Takara, N. Tamai, K. in streams that had surface waters that were Creed Jr., R. P., & Reed, J. M., 2004. Ecosystem Kawai, T., Kawajiri, H., Kumagai, T., & Ashikari, Nonomura & M. Fujiyosi, (eds.), Encyclopedia infiltrated during the dry season (Nunokawa, engineering by crayfish in a headwater stream H., 2006. Blue color variants of the Japanese of River, Maruzen, Tokyo, 428–428 (in M., Tanaka, K. & Ikeda, K. personal community. Journal of the North American freshwater crayfish Cambaroides japonicus Japanese). communication). It is likely that C. japonicus Benthological Society, 23: 224–236. in Hokkaido, Japan. Bulletin of the Bihoro Statzner, B., Fievet, E., Champagne, J. Y., Morel, R., Ikeda, K., & Nunokawa, M., 2011. New method Museum, 14: 55–62 (in Japanese with English & Herouin, E., 2000. Crayfish as geomorphic creates burrows easily in habitats with fine for measuring physical variables: Qualification summary). agents and ecosystem engineers: Biological substrate. Although there are few boulders of substrate environments in Japanese crayfish Kawai, T., Koga, T., & Arai, S., 2004b. behavior affects sand and gravel erosion in that function as shelter from predators (Usio, habitat. In: T. Kawai & K. Nakata, (eds.), Environments of the habitats of the Japanese experimental streams. Limnology Oceanography, 2007) in small creek habitats, small substrate Shrimp, crab, crayfish: Conservation and biology crayfish Cambaroides japonicus (De Haan, 45: 1030–1040. items probably serve as alternative refugia of freshwater crustaceans. Seibutsu–Kenkyuusha, 1841) in Lake Shiribeshi, Hokkaido, Japan. Statzner, B., Peltret, O., & Tomanova, S., 2003. for C. japonicus in these locations. Tokyo, 30–308 (in Japanese). Bulletin of the Sapporo Salmon Museum, 16: Crayfish as geomorphic agents and ecosystem Ishiyama, N., Nagayama, S., Akasaka, T., & 19–23 (in Japanese). engineers: effect of a biomass gradient on In this study, we found that small creek Nakamura, F., 2012. Habitat use by endangered Kawai, T., & Nakata, K., 2001. On a collection baseflow and flood–induced transport of gravel habitats were inhabited by C. japonicus and Japanese crayfish (Cambaroides japonicus) in method using miso (soybean paste) and burrow and sand in experimental streams. Freshwater documented environmental variables that low–gradient streams of southern Hokkaido, utilization of the Japanese crayfish Cambaroides Biology, 48: 147–163. define such habitats. In addition, our results Japan: Reach and microhabitat–scale analysis. japonicus (De Haan, 1841). Journal of the Tanaka, K., 2011. Habitat status and environments suggest that C. japonicus creates burrows as Hydrobiologia, 686:257–266. Natural History of Aomori, 6: 49–52 (in Japanese of the endangered Japanese crayfish: a regional shelters in fine substrates. We observed large Japanese Crayfish Research Group, 2005. Current with English abstract). comparison between Otaru and Nopporo numbers of this species in these habitats distribution of Japanese crayfish Cambaroides Kawai, T., Nakata, K., Hirata, M., & the Otofuke habitats. Open Forum, 7: 60–65 (in Japanese). japonicus, in Otaru City, Hokkaido, Japan. River Ground Group, 2000. Distribution of Usio, N., & Townsend, C. R., 2001. The significance (Nunokawa, M., Tanaka, K. & Ikeda, K. Bulletin of the Otaru Museum, 18: 1–15 (in crayfishes in the central region of Tokachi, of the crayfish Paranephrops zealancus as personal communication). It is important to Japanese with English abstract). Hokkaido, Japan. Bulletin of the Obihiro shredders in a New Zealand headwater stream. recognize and manage small creek habitats to Jones, C. G., Lawton, J. H., & Shachak, M., 1994. Centennial Museum, 18: 1–8 (in Japanese with Journal of Crustacean Biology, 21: 354–359. conserve C. japonicus populations. Organisms as ecosystem engineers. Oikos, 69: English abstract). Usio, N., 2007. Endangered crayfish in northern 373–386. Kawai, T., Nakata, K., & Suzuki, Y., 2001. Japan: Distribution, abundance and microhabitat Kawai, T., 1992. Burrow of a Japanese crayfish Decreasing habitat conditions of the Japanese specificity in relation to stream and riparian Acknowledgments.—We thank I. Kobayashi Cambaroides japonicus (DE HAAN, 1841). crayfish Cambaroides japonicus (De Haan, environment. Biological Conservation, 134: (Pacific Consultants Co., LTD), H. Yamada Research for Crustacea, 21: 65–71. 1841) in and around Sapporo City. Bulletin of 517–526. (Pacific Consultants Co., LTD), Dr. K. Kawai, T., 1993. Environment of the habitat of the the Sapporo Salmon Museum, 13: 21–26 (in Yamada, H., Nunokawa, M., & Kawai, T., 2008. Mikami (Hokkaido College, Senshu Japanese crayfish Cambaroides japonicus in Japanese). Habitat preference of the Japanese crayfish University), S. Otsuki, N. Kawamura (Shin Lake Komadome. The Bulletin of the Obihiro Kawai, T., Nunokawa, M., & Yamada, H., 2009. (Cambaroides japonicus) in the small stream and Centennial City Museum, 11: 1–6 (in Japanese Distribution of crayfishes in Hokkaido Japan, the effective capture methods. Proceedings of the Engineering Consultants Co., LTD), K. Inabe with English abstract). with habitat loss of the Japanese crayfish Symposium on Wildlife and Traffic, 11: 57–60 (in CHARACTERISTICS OF CRAYFISH CREEKS IN JAPAN 139 138 ET AL. 139 M. NuNokawa(Iwaki Zoen), Y. Fuji (Kesen–numa Forestry Kawai, T., 1994. Distribution and habitat of the Cambaroides japonicus. Journal of Community habitats was likely because the stream Japanese crayfish Cambaroides japonicus Cooperative Research Center, Senshu University, habitats experienced such geomorphological Corporative), and N. Watanabe (Hokkaido in Hokkaido, Japan. Bulletin of the Higashi 4: 51–56 (in Japanese with English abstract). processes. University) for participating in our research Taisetsu Museum of Natural History, 16: 21–24 Mann, H. B., & Whitney, D. R., 1947. On a test of Small creeks had fine substrates (Fig. activities. We thank S. Ohira, T. Takishita, (in Japanese with English summary). whether one of two variables is stochastically 1). However, there were no significant H. Maezawa, K. Otani, and K. Usuda for Kawai, T., 1995. Refuge and fecundity of the larger than the other. Annals of Mathematical differences in mean substrate coarseness providing us with the opportunity to conduct Japanese crayfish, Cambaroides japonicus, in Statistics 18:50–60. a stream and a small lake, in Hokkaido, Japan. Miyake, S., 1982. Illustrated colored encyclopedia of between stream and small creek habitats. our research and for providing general research information. Bulletin of the Higashi Taisetsu Museum of Japanese macro–crustacean 1., 261pp, Hoikusha, Most small creek habitats were dominated Natural History, 17: 73–77 (in Japanese with Osaka (in Japanese). by coarse and fine sand substrates, but English summary). Merritt, R., & Cummins, K. W., 1996. An some creek habitats were dominated by Kawai, T., 1996. Distribution of the Japanese introduction to the aquatic insects of North LITeRATURe CITeD fine sand and silt, or fine sand and pebbles. crayfish, Cambaroides japonicus, in Hokkaido, America, 3rd (ed.), Kendall–Hunt, Dubuque. Creek habitats had a depositional trend in Abe, T., & Nunokwa, M., 2005. Food web analysis Japan and its loss of habitat in Eastern Hokkaido. Nakata, K., Kawai, T., & Goshima, S., 2003a. their sediments because these habitats had using stable isotopes in a forested stream in Memoirs of the Kushiro City Museum, 20: 5–12 Rediscovery of the Japanese crayfish spring. Journal of the Japanese Forest Society, (in Japanese with English abstract). Cambaroides japonicus in Lake Shikaribetsu, extremely shallow depths and low water 87: 13–19 (in Japanese with English abstract). Kawai, T., 2007. Habitat of Cambaroides japonicus. Hokkaido, Japan. The Bulletin of the Higashi velocities. Small creek habitats had greater Bain, M. B., Finn, J. T., & Booke, H. E., 1985. In natural history of crayfish–An introduction to Taisetsu Museum of Natural History, 25: 61–66 variation in substrate values than did streams. Quantifying stream substrate for habitat analysis Satokawa Gaku, Tokai University Press, Tokyo, (in Japanese with English summary). Therefore, substrate coarseness did not show studies. North American Journal of Fisheries 41–53 (in Japanese). Nakata, K., Hamano, T., Hayashi, K., & Kawai, T., any significant difference between habitats. Management, 5: 499–506. Kawai, T., Hori, S., Mizushima, M., & Nagasaka, 2003b. Water velocity in artificial habitats of Bisson, P. A., Montgomery, D. R., & Buffington, J. Y., 2004a. Distribution and present status of the Japanese crayfish Cambaroides japonicus. C. japonicus creates burrows, which M., 2006. Valley segments, stream reaches, and the Japanese crayfish (Cambaroides japonicus) Fisheries Science, 69: 343–347. are filled with subsurface water, allowing channel units. In: F. R. Hauer & G. A. Lamberti, population in the Nopporo Forest Park. The Nunokawa, M., 2009. Classification by feeding crayfish to survive in the burrows during the (eds.), “Methods in stream ecology, 2nd ed.”, Memoirs of the Historical Museum of Hokkaido, functional group. In Y., Takahashi, T. Iwaya, winter. There were no crayfish populations Aacademic Press. Burlington, 23–49. 43: 33–38 (in Japanese with English abstract). T. Oki, Y. Shimatani, K. Takara, N. Tamai, K. in streams that had surface waters that were Creed Jr., R. P., & Reed, J. M., 2004. Ecosystem Kawai, T., Kawajiri, H., Kumagai, T., & Ashikari, Nonomura & M. Fujiyosi, (eds.), Encyclopedia infiltrated during the dry season (Nunokawa, engineering by crayfish in a headwater stream H., 2006. Blue color variants of the Japanese of River, Maruzen, Tokyo, 428–428 (in M., Tanaka, K. & Ikeda, K. personal community. Journal of the North American freshwater crayfish Cambaroides japonicus Japanese). communication). It is likely that C. japonicus Benthological Society, 23: 224–236. in Hokkaido, Japan. Bulletin of the Bihoro Statzner, B., Fievet, E., Champagne, J. Y., Morel, R., Ikeda, K., & Nunokawa, M., 2011. New method Museum, 14: 55–62 (in Japanese with English & Herouin, E., 2000. Crayfish as geomorphic creates burrows easily in habitats with fine for measuring physical variables: Qualification summary). agents and ecosystem engineers: Biological substrate. Although there are few boulders of substrate environments in Japanese crayfish Kawai, T., Koga, T., & Arai, S., 2004b. behavior affects sand and gravel erosion in that function as shelter from predators (Usio, habitat. In: T. Kawai & K. Nakata, (eds.), Environments of the habitats of the Japanese experimental streams. Limnology Oceanography, 2007) in small creek habitats, small substrate Shrimp, crab, crayfish: Conservation and biology crayfish Cambaroides japonicus (De Haan, 45: 1030–1040. items probably serve as alternative refugia of freshwater crustaceans. Seibutsu–Kenkyuusha, 1841) in Lake Shiribeshi, Hokkaido, Japan. Statzner, B., Peltret, O., & Tomanova, S., 2003. for C. japonicus in these locations. Tokyo, 30–308 (in Japanese). Bulletin of the Sapporo Salmon Museum, 16: Crayfish as geomorphic agents and ecosystem Ishiyama, N., Nagayama, S., Akasaka, T., & 19–23 (in Japanese). engineers: effect of a biomass gradient on In this study, we found that small creek Nakamura, F., 2012. Habitat use by endangered Kawai, T., & Nakata, K., 2001. On a collection baseflow and flood–induced transport of gravel habitats were inhabited by C. japonicus and Japanese crayfish (Cambaroides japonicus) in method using miso (soybean paste) and burrow and sand in experimental streams. Freshwater documented environmental variables that low–gradient streams of southern Hokkaido, utilization of the Japanese crayfish Cambaroides Biology, 48: 147–163. define such habitats. In addition, our results Japan: Reach and microhabitat–scale analysis. japonicus (De Haan, 1841). Journal of the Tanaka, K., 2011. Habitat status and environments suggest that C. japonicus creates burrows as Hydrobiologia, 686:257–266. Natural History of Aomori, 6: 49–52 (in Japanese of the endangered Japanese crayfish: a regional shelters in fine substrates. We observed large Japanese Crayfish Research Group, 2005. Current with English abstract). comparison between Otaru and Nopporo numbers of this species in these habitats distribution of Japanese crayfish Cambaroides Kawai, T., Nakata, K., Hirata, M., & the Otofuke habitats. Open Forum, 7: 60–65 (in Japanese). japonicus, in Otaru City, Hokkaido, Japan. River Ground Group, 2000. Distribution of Usio, N., & Townsend, C. R., 2001. The significance (Nunokawa, M., Tanaka, K. & Ikeda, K. Bulletin of the Otaru Museum, 18: 1–15 (in crayfishes in the central region of Tokachi, of the crayfish Paranephrops zealancus as personal communication). It is important to Japanese with English abstract). Hokkaido, Japan. Bulletin of the Obihiro shredders in a New Zealand headwater stream. recognize and manage small creek habitats to Jones, C. G., Lawton, J. H., & Shachak, M., 1994. Centennial Museum, 18: 1–8 (in Japanese with Journal of Crustacean Biology, 21: 354–359. conserve C. japonicus populations. Organisms as ecosystem engineers. Oikos, 69: English abstract). Usio, N., 2007. Endangered crayfish in northern 373–386. Kawai, T., Nakata, K., & Suzuki, Y., 2001. Japan: Distribution, abundance and microhabitat Kawai, T., 1992. Burrow of a Japanese crayfish Decreasing habitat conditions of the Japanese specificity in relation to stream and riparian Acknowledgments.—We thank I. Kobayashi Cambaroides japonicus (DE HAAN, 1841). crayfish Cambaroides japonicus (De Haan, environment. Biological Conservation, 134: (Pacific Consultants Co., LTD), H. Yamada Research for Crustacea, 21: 65–71. 1841) in and around Sapporo City. Bulletin of 517–526. (Pacific Consultants Co., LTD), Dr. K. Kawai, T., 1993. Environment of the habitat of the the Sapporo Salmon Museum, 13: 21–26 (in Yamada, H., Nunokawa, M., & Kawai, T., 2008. Mikami (Hokkaido College, Senshu Japanese crayfish Cambaroides japonicus in Japanese). Habitat preference of the Japanese crayfish University), S. Otsuki, N. Kawamura (Shin Lake Komadome. The Bulletin of the Obihiro Kawai, T., Nunokawa, M., & Yamada, H., 2009. (Cambaroides japonicus) in the small stream and Centennial City Museum, 11: 1–6 (in Japanese Distribution of crayfishes in Hokkaido Japan, the effective capture methods. Proceedings of the Engineering Consultants Co., LTD), K. Inabe with English abstract). with habitat loss of the Japanese crayfish Symposium on Wildlife and Traffic, 11: 57–60 (in 140 140 ET AL. Japanese). M. NuNokawa7, Kita–ku, Sapporo, 060–0810 Japan, (KI) Pacific Consultants Co., LTD., (PCKK), 2–6, Addresses: (MN) Research Faculty of Kita 7, Nishi 1, Kita–ku, Sapporo, 060–0807 REVIEWERS Agriculture, Hokkaido University, Kita 9, Japan; Nishi 9, Kita-ku, Sapporo, Hokkaido, 060- Emails: (MN) [email protected], (KT) 8589, Japan, (KT) Graduate School of [email protected], (KI) Kousuke. The editor thanks the following referees who have reviewed manuscripts submitted Letters, Hokkaido University, Kita 10, Nishi [email protected] for publication in Special Issues of Crustacean Research: Conservation of freshwater crayfish.

Curt Fiedler Takashi Gomi Premek Hamr Kazuyoshi Hashizume Nobuo Ishiyama Japo Jussila Takashi Kikkawa Souhei Koayashi Antonio Kouba Pavel Kozak Filipova Lenka Ivana Maguire Alastair Richardson Erich Rudolph Nobuhiro Saito Jun Sasaki Christopher Taylor Roger Thoma Elena Tricarico You Usami Izumi Yamasaki