Title | Ephemeral floodplain habitats provide best growth conditions for juvenile Chinook salmon in a California river |
Publication Type | Journal Article |
Year of Publication | 2008 |
Authors | Jeffres, C., Opperman J.J., & Moyle P. B. |
Journal | Environmental Biology of Fishes |
Volume | 83 |
Issue | 4 |
Start Page | 449 |
Date Published | 06/2008 |
Keywords | Floodplain, Growth, Juvenile Chinook, Rearing, Restoration |
Abstract | We reared juvenile Chinook salmon for two
consecutive flood seasons within various habitats of
the Cosumnes River and its floodplain to compare
fish growth in river and floodplain habitats. Fish were
placed in enclosures during times when wild salmon
would naturally be rearing in floodplain habitats. We
found significant differences in growth rates between
salmon reared in floodplain and river enclosures.
Salmon reared in seasonally inundated habitats with
annual terrestrial vegetation experienced higher
growth rates than those reared in a perennial pond
on the floodplain. Growth of fish in the non-tidal river
upstream of the floodplain varied with flow in the
river. When flows were high, there was little growth
and high mortality, but when the flows were low and
clear, the fish grew rapidly. Fish displayed very poor
growth in tidally influenced river habitat below the
floodplain, a habitat type to which juveniles are
commonly displaced during high flow events due to
a lack of channel complexity in the main-stem river.
Overall, ephemeral floodplain habitats supported
higher growth rates for juvenile Chinook salmon than
more permanent habitats in either the floodplain or
river. Variable responses in both growth and mortality,
however, indicate the importance of providing habitat
complexity for juvenile salmon in floodplain reaches
of streams, so fish can find optimal places for rearing
under different flow conditions. |
URL | http://www.springerlink.com/content/e873456118pjl537/ |
DOI | 10.1007/s10641-008-9367-1 |