Illustrating the value of cross-site comparisons: Habitat use by a large, euryhaline fish differs along a latitudinal gradient

摘要: Abstract Plasticity in life-history traits and behaviors allows organisms to track spatial environmental variation, such as that resulting from a latitudinal gradient. In estuaries, hydrological patterns can vary greatly with latitude, causing variable habitat use across species’ range. For Common Snook (Centropomus undecimalis) large euryhaline fish, seasonal movements between the open estuary freshwater reaches of rivers have been documented. We hypothesized timing river by would be driven primarily magnitude inflow, except at northern limit its range where lethal water temperatures may stronger influence. Data electrofishing studies (2012–2016) conducted associated four estuaries along gradient western Florida were compared for differences abundance using negative binomial regression. southwestern (those Everglades Charlotte Harbor), abundances increased three-fold during time year when surface waters inundating floodplains recede force prey into main stems rivers. These hydrologically processes, surges abundance, occurred spring fall Harbor. Tampa Bay rivers, which less inflow than farther south, differed little seasons. spring-fed north Bay, winter twice those summer; stable thought provide thermal refuge northernmost Snook. This work illustrates how species, underlying reasons, differ among sites. It also demonstrates value cross-site comparisons providing more complete understanding species uses available habitats