Spatiotemporal variability of stream habitat and movement of three species of fish

Abstract

Relationships between environmental variability and movement are poorly understood, due to both their complexity and the limited ecological scope of most movement studies. We studied movements of fantail (Etheostoma flabellare), riverweed (E. podostemone), and Roanoke darters (Percina roanoka) through two stream systems during two summers. We then related movement to variability in measured habitat attributes using logistic regression and exploratory data plots. We indexed habitat conditions at both microhabitat (i.e., patches of uniform depth, velocity, and substrate) and mesohabitat (i.e., riffle and pool channel units) spatial scales, and determined how local habitat conditions were affected by landscape spatial (i.e., longitudinal position, land use) and temporal contexts. Most spatial variability in habitat conditions and fish movement was unexplained by a site's location on the landscape. Exceptions were microhabitat diversity, which was greater in the less-disturbed watershed, and riffle isolation and predator density in pools, which were greater at more-downstream sites. Habitat conditions and movement also exhibited only minor temporal variability, but the relative influences of habitat attributes on movement were quite variable over time. During the first year, movements of fantail and riverweed darters were triggered predominantly by loss of shallow microhabitats; whereas, during the second year, microhabitat diversity was more strongly related (though in opposite directions) to movement of these two species. Roanoke darters did not move in response to microhabitat-scale variables, presumably because of the species' preference for deeper microhabitats that changed little over time. Conversely, movement of all species appeared to be constrained by riffle isolation and predator density in pools, two mesohabitat-scale attributes. Relationships between environmental variability and movement depended on both the spatiotemporal scale of consideration and the ecology of the species. Future studies that integrate across scales, taxa, and life-histories are likely to provide greater insight into movement ecology than will traditional, single-season, single-species approaches.

Fish movement in an Atlantic Forest stream

“…These results indicate that species differ in their movement patterns, as already shown in many other studies (e.g. Skalski, Gilliam, 2000;Albanese et al, 2004;Roberts, Angermeier, 2007;Breen et al, 2009). The longest distance registered in this study was performed by an individual of A. tajasica that moved approximately 1,500 m. Awaous tajasica is an estuarine Gobiidae species that normally move upstream into freshwater environments (Loebmann, Vieira, 2005).…”

“…Short distance movements (local) are generally related to changes in resources availability (Albanese et al, 2004), like food or refuge (Gowan, Fausch, 2002;Gowan, 2007), predation risk (Roberts, Angermeier, 2007), or to abiotic conditions like salinity, stream flow Romão et al, 2017), and dissolved oxygen (Branco et al, 2016). Local movements can also be related to ontogeny, being an important life-history trait for several species (Winemiller, Jepsen, 1998).…”

Coarse-scale movement patterns of a small-bodied fish inhabiting a desert stream

“…Studies assessing relationships between length and movement distances have mixed results (Albanese et al 2004;Belica and Rahel 2007;Roberts and Angermeier 2007;Albanese et al 2009). In an experimental study assessing emigration of C. macularius, McMahon and Tash (1988) documented that small male fish were more likely to emigrate compared to large and/or female fish.…”

“…Movement rate was expressed as the proportion of recaptures that were movers (Roberts and Angermeier 2007). Because our sampling design included multiple re-visits to sites within the same day (i.e., multiple 'collections'), we could not claim that collections from the same site were independent.…”

“…Specifically, potential benefits (e.g., improved abiotic conditions and reduced competition) of movement are countered by risks or barriers to movement (e.g., predation and habitat connectivity), both of which vary by species and life history state (Albanese et al 2004;Davey and Kelly 2007;Roberts and Angermeier 2007). Studies that estimate movement can help determine the importance of connectivity in aquatic systems (Johnston 2000;Fausch et al 2009) as well as increase understanding of species' life history (e.g., Goforth and Foltz 1998;Roberts and Angermeier 2007). For example, because harsh environmental conditions in desert stream environments could be partly offset by habitat complexity and diversity of refugia, studies evaluating movement may help biologists determine the role of refugia in population persistence (Labbe and Fausch 2000;Magoulick and Kobza 2003).…”