Patterns of fish species distributions replicated across three parallel rivers suggest biotic zonation in response to a longitudinal temperature gradient

Abstract

Environmental gradients determine the distributions of individual species, which, in turn, shape patterns of species assemblage across those gradients. We used species distribution models to study the assemblage of fish species along the three mainstem rivers in the South Saskatchewan River Basin (SSRB) in Alberta, which flow in parallel across an 800‐km longitudinal span and down 1400 m from the Rocky Mountains to the Great Plains of North America. We estimated the similarity of species assemblages along each river to identify general patterns of species assemblage associated with temperature and five other physiochemical variables. Mean July water temperature, which ranged from <11°C at high elevation to >21°C at low elevation, was strongly associated with the presence–absence of most species in the SSRB. We found that high turnover occurred at two locations along the longitudinal gradient: where mean July water temperature was approximately 15°C and where mean July water temperature was approximately 19 or 20°C. There was also an increase in species richness at lower elevations where water temperatures were higher. Models incorporating forecasted changes in water temperature with climate change will likely provide accurate predictions of changes in the diversity and distribution of riverine fish communities across topographically heterogeneous landscapes.

Integrating Fish Assemblage Data, Modeled Stream Temperatures, and Thermal Tolerance Metrics to Develop Thermal Guilds for Water Temperature Regulation: Wyoming Case Study

“…This is similar to the coolwater range of approximately 15°C through 19–20°C for mean July water temperature identified in three rivers in the South Saskatchewan River basin in Alberta, Canada, another Rocky Mountain headwaters system (Mee et al. ). The range of coolwater habitat identified in the eastern and Midwestern United States is slightly warmer; the coolwater range of mean July water temperature in Connecticut was defined as 18.5–22.3°C (Beauchene et al.…”

“…The range of modeled mean August water temperatures at sites identified as coolwater habitat in Wyoming is 15.5°C through 19.9°C. This is similar to the coolwater range of approximately 15°C through 19-20°C for mean July water temperature identified in three rivers in the South Saskatchewan River basin in Alberta, Canada, another Rocky Mountain headwaters system (Mee et al 2018). The range of coolwater habitat identified in the eastern and Midwestern United States is slightly warmer; the coolwater range of mean July water temperature in Connecticut was defined as 18.5-22.3°C (Beauchene et al 2014) and the coolwater range of June-August mean water temperature in Wisconsin and Michigan was defined as 17-20.5°C (Lyons et al 2009).…”

Temperature‐dependent competition between juvenile salmonids in small streams

“…In lotic environments, zonation patterns of stream fishes along the river continuum from headwaters to mouth are common (Fausch, Nakano, & Ishigaki, 1994;Mee, Robins, & Post, 2018), where ecologically similar species replace each other with little overlap (de la Hoz Franco & Budy, 2005;McHugh & Budy, 2005). Regarding the generality of temperature-mediated competition as a main driver for the spatial segregation of stream fishes along temperature gradients, laboratory experiments, however, show conflicting results (Carmona-Catot, Magellan, & García-Berthou, 2013;Hitt, Snook, & Massie, 2016;Magoulick & Wilzbach, 1998;McMahon, Zale, Barrows, Selong, & Danehy, 2007;Taniguchi & Nakano, 2000;Taniguchi, Rahel, Novinger, & Gerow, 1998).…”

Modelling the possible impacts of climate change on the thermal regime and macroinvertebrate species of a regulated prairie river

“…The thermal regime is a key consideration for instream flow management (Olden & Naiman, 2010) as the ecological integrity of river ecosystems is dependent on the natural dynamics of temperature range and spatiotemporal characteristics. For example, temperature is known to determine physiology and metabolic rates of organisms (Catenazzi & Kupferberg, 2018;Tao, Kennard, Jia, & Chen, 2018), fecundity (Farrell, 2009), recruitment and mortality (Catenazzi & Kupferberg, 2018;Coulter, Sepúlveda, Troy, & Höök, 2016;Gaufin & Hern, 1971), and influence species distribution (Howell, 2017;Mee, Robins, & Post, 2016). Regulated rivers around the world generally exhibit altered temperature magnitudes, rates of change, and timing characteristics (Cai et al, 2018;Casado, Hannah, Peiry, & Campo, 2013) compared with preregulation conditions (Maheu et al, 2016).…”