Realm: Freshwater
Climate: Temperate
Biome: Small river ecosystems
Central latitude: 44.771342
Central longitude: 142.165976
Duration: 20 years, from 1999 to 2018

57062 records

11 distinct species

Across the time series Barbatula barbatula is the most frequently occurring species

Methods

The fish sampling was conducted from 1999 to 2018 in five streams of Teshio River system. Among these streams, the planted Otoineppu bypass route of national road intersects three streams (Kotohira stream, Tonbetsubou stream, and Katounosawa stream) (Figure 1). They were considered as bypass road construction streams because the road construction may affect fish community and stream environmental characteristics. In contrast, the two other streams (Toyomanai stream and Tentonosawa stream) were not intersected by the planted bypass route. They were considered as control streams. Toyomanai stream is about 7.4 km in length and is control stream. This stream has two sampling sites (A1 and A2) (Table 2). Between them, there is an erosion control dam without fishway (Figure 1). Kotohira stream is about 11.5 km in length and is bypass road construction streams. This stream has five sampling sites (B1B5). In the autumn of 2009, a fishway was established in the erosion control dam between B3 and B4. In the summer of 2010, a fishway was established in the dam between B4 and B5. In the winter of 2013, the dam upstream of B5 was modified with slit (Umatani & Okuda, 2017). In addition, hatchery-reared chum salmon were released in the spring from 2005 to 2009. Tonbetsubou stream is about 5.9 km in length and is bypass road construction streams. This stream has one sampling site (C1). Katounosawa stream is about 2.3 km in length and is bypass road construction streams. This stream has one sampling site (D1). Tentonosawa stream is a tributary of Otoineppu stream about 14.3 km in length and is control stream. This stream has one sampling site (E1). At each sampling site, fish were sampled in a length of approximately 50?m. The fish sampling was conducted three times a year from 1999 to 2018 (mainly June, August and October). However, the sampling was not conducted for some sites and some periods (Table 3). The three?pass removal method using an electrofishing unit (Smith?Root, model 12B or LR24) was performed for sampling fishes. The three?pass removal method is to repeat the sampling of fish in a 50?m channel three times at each site to estimate the fish population at each site (DeLury, 1951). However, the single?pass removal method was used for A1 in autumn of 2005 and B4 in autumn of 2007. The sampled fish were anesthetized with 2?phenoxyethanol and species or taxon was identified. Body size and body weight were measured to the nearest 1?mm (Body size of the cyprinid and salmonid fish was measured by fork length, the other species was measured by total length) and the nearest 0.1 g, respectively. After awakening, the sampled fish were released. Although immature individuals of Tribolodon were sampled in these streams, they (e.g., T. hakonensis, T. sachalinenisis and T. brandtii) were difficult to identify the species in the field. Thus, they were treated as Tribolodon sp. Also, individuals of Lethenteron (e.g., L. sp. N and L. japonicum) were treated as Lethenteron sp., and they are divided into ammocoetes larvae and adult since 2009.

Citation(s)

@Article{BioTIME_cit372, Study_id = {611}, Citation_id = {372}, Author = {Umatani, Yoshiyuki and Okuda, Atsushi and Fujito, Eishi and Yoshida, Toshiya and Satoh, Fuyuki and Maekawa, Koji and Nakamura, Masahiro}, Journal = {Ecological Research}, Pages = {986-993}, Title = {Long?term observation of fish community in streams inside and outside road construction of Teshio River system, northern Hokkaido, Japan}, Volume = {35}, Year = {2020}, Doi = {10.1111/1440-1703.12133}, Language = {English} }