Low-Head Barrier Dams Restrict the Movements of Fishes in Two Lake Ontario Streams

Abstract

The Great Lakes Fishery Commission (GLFC) is considering greater use of low‐head barrier dams on stream tributaries of the Laurentian Great Lakes to control populations of sea lampreys Petromyzon marinus. The impact of these barriers on nontarget fishes is not known. A mark–recapture study on four Lake Ontario streams examined movements of fishes in streams with (barrier) and without (reference) low‐head barriers. A significantly lower proportion of fishes moved across a real barrier on barrier streams than across a hypothetical barrier on reference streams (0.15 versus 0.50, respectively). The impact of the barriers on movement was more pronounced in spring and fall than in summer. However, the likelihood of fishes moving versus not moving between sample segments on either side of a barrier location (but not across the barrier) did not differ significantly between barrier and reference streams. The upstream (longitudinal) decline in species richness was greater for barrier streams than for reference streams in each season. At both interspecific and intraspecific levels, mean total lengths of fish traversing real barriers were significantly greater than the mean total lengths of fish traversing hypothetical barriers. Our findings demonstrate that low‐head barriers restrict the movements of some fishes and suggest this restriction affects assemblage structure above the barrier.

Influences of low-head dams on the fish assemblages in the headwater streams of the Qingyi watershed, China

“…Low-head dams may block the migratory pathway of fish and thereby cause the local extinction of fish species and the decrease of species richness in the stream segments upstream (Winston et al 1991;Porto et al 1999). The impacts of low-head dams on fish species are perhaps associated with species traits (e.g., swimming ability) (Helfrich et al 1999).…”

“…Till now, the pattern of how low-head dams impact fish assemblages still remains debated and unclear (Gillette et al 2005;Poulet 2007). Winston et al (1991) and Porto et al (1999) found the obstacle role of low-head dams on fish passage, resulting in the local extinction of migratory fish. Helfrich et al (1999) discovered that fish species traits (e.g., swimming ability) appeared to be related to low-head dam passage, and they observed the cumulative effect of multiple low-head dams on fish assemblages.…”

Fish movement in an Atlantic Forest stream

“…Mortality, stress by handling and tag losses are among the causes of low recapture rates (Porto et al, 1999;Smithson, Johnston, 1999 Josephson et al, 2008;Carvalho-Souza et al, 2010;Soula et al, 2012) as well as low mortality caused by tagging procedures (e.g. Riley et al, 1992).…”

Fish Passage in a Western Iowa Stream Modified by Grade Control Structures

“…In rivers around the world, countless instream structures are barriers to fish passage (Porto et al 1999;Pringle et al 2000). Movement, whether short distances between habitat patches or long migrations in streams, is vital to survival and reproductive success of many stream fishes (Pringle et al 2000).…”

“…Over time, restricted fish passage may result in reduced fish abundance and species richness (Joy and Death 2001), fragmentation of populations and genetic divergence (Pringle et al 2000;Morita and Yamamoto 2002), shifts in fish assemblages in areas upstream and downstream from impoundments (Taylor et al 2001;Gehrke et al 2002), and possible extirpation of species in reaches upstream from barriers (Winston et al 1991;Taylor et al 2001). Although a great deal of past research has investigated fish passage through large barriers (i.e., dams built for hydroelectricity production and reservoir construction) and the corresponding changes in river fish communities resulting from these impoundments, small structures, such as low-head dams and road crossings, also present serious barriers to fish passage that may adversely affect fish populations and communities (Warren and Pardew 1998;Porto et al 1999;Ovidio and Philippart 2002;Santucci et al 2005).…”