Ephemeral floodplain habitats provide best growth conditions for juvenile Chinook salmon in a California river. by Carson A.

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1 Ephemerl floodplin hbitts provide best growth conditions for juvenile Chinook slmon in Cliforni river by Crson A. Jeffres Abstrct We rered juvenile Chinook slmon for two consecutive flood sesons within vrious hbitts of the Cosumnes River nd its floodplin (Cliforni) to compre growth rtes of in river nd newly creted floodplin hbitts. Fish were plced in enclosures in severl different hbitt types on the floodplin nd in the river during times when wild slmon would nturlly be rering in floodplin hbitts. We found significnt differences in growth rtes between slmon rering in floodplin nd river sites. Slmon rered in sesonlly inundted hbitts with nnul terrestril vegettion showed higher growth rtes thn those rered in perennil pond on the floodplin. Growth of fish in the river upstrem of the floodplin vried with flow nd turbidity in the river. When flows nd turbidity were high, there ws little growth nd high mortlity, but when the flows were low nd cler, the fish grew rpidly. Fish in tidl river hbitt below the floodplin in showed very poor growth rtes. Overll, ephemerl floodplin hbitts supported higher growth rtes for juvenile Chinook slmon thn more permnent hbitts in either the floodplin or river. Introduction Temperte rivers nd their floodplins hve been hevily ltered to meet demnds of n expnding humn popultion (Richter et l. 2003). Dms store wter for purposes of flood protection nd griculturl nd municipl wter supply nd thereby reduce or

2 eliminte nturl flood flows. Mny rivers hve been chnnelized nd re flnked by levees, which further reduces connectivity between river nd floodplin except during extremely high dischrge events (Mount 1995, Tockner nd Stnford 2002). In the lst two decdes, numerous studies hve demonstrted tht both qutic nd terrestril orgnisms s well s ecosystems benefit from dynmic connectivity between rivers nd floodplins. Floodplin species benefit from nutrients mobilized by inundtion of riprin res (Junk et l. 1989), while riverine species benefit by hving ccess to the floodplin for forging, spwning, nd s refuge from high velocities found in the river during high flow events (Moyle et l. submitted). Fish yields in wtersheds generlly increse when wter surfce re in floodplins is incresed (Byley 1991). Floodplins hve lso been shown to be beneficil to species tht use the min stem of the river primrily s migrtion corridor nd secondrily s rering re, such s juvenile ndromous slmonids (Brown nd Hrtmn 1988). Sommer et l. (2001) found tht Juvenile Chinook slmon tht rered within lrge, engineered floodplin of the Scrmento River (the Yolo Bypss) hd higher rtes of growth nd survivl thn fish tht rered in the min-stem river chnnel during their migrtion. In this study, we build on the work of Sommer et l. (2001) nd experimentlly compre juvenile Chinook slmon growth between different hbitt types of more complex nturl river-floodplin system. We exmine in detil how different floodplin nd riverine hbitts influence the growth of juvenile slmon in the Cosumnes River, n undmmed river flowing out of the Sierr Nevd, in centrl Cliforni. In this river, the first mjor rins in the fll llow dult fll-run Chinook slmon to migrte upstrem to spwn. Slmon fry emerge from the grvel during winter when flows re elevted from

3 frequent precipittion events (Florsheim nd Mount 2002). With the increse in flow, fry both ctively nd pssively migrte downstrem (Heley 1980; Kjelson et l. 1981). In the lower reches of the river, lrge portion of the totl river flow enters the floodplin during high river stges. Flows from both the river nd floodplin then enter the intertidl wters of the Scrmento-Sn Joquin Delt (Figure 1)(Swenson et l 2003). Thus, juvenile Chinook rer in three primry hbitt types of the lower Cosumnes: the min-stem river chnnel, the floodplin, nd the tidl Delt. Sommer et l. (2001) demonstrted tht temporrily flooded hbitt in n rtificil floodplin in the Centrl Vlley produced superior growth of juvenile Chinook slmon compred to river hbitts. Here we evlute how differences in growth occur in different hbitts in more complex nturl floodplins nd their ssocited rivers. Lnd mngers nd government gencies re investing significnt resources in floodplin restortion (CALFED 2004) nd, thus, require informtion on the ecologicl benefits ssocited with vrious types of floodplin hbitt (e.g., nnul vegettion, forest, sesonl wetlnd, permnent pond/wetlnd). Further, mny physicl prmeters ultimtely determine wht hbitt is vilble to the mny species tht rely on floodplins for growth, reproduction nd survivl. Fctors such s mgnitude nd durtion of floods ply n importnt role in determining qulity nd ccessibility of vrious floodplin hbitts. We compred growth rtes of juvenile Chinook slmon in enclosures plced in different hbitts within the Cosumnes River floodplin, s well s in djcent river nd intertidl hbitts, during two yers with different flooding regimes. Our bsic hypothesis ws tht juvenile slmon in ephemerl floodplin hbitts experience higher growth rtes thn juvenile slmon in other floodplin hbitts or in djcent river or tidl hbitts.

4 Methods Study Are The Cosumnes River wtershed is unusul for Sierr Nevd river becuse there re no mjor dms on the min-stem nd the river is reltively free flowing (Figure 1). The Cosumnes River wtershed encompsses ~2000 km 2 nd origintes t n elevtion of 2357 m nd flows into the Mokelumne River in the Scrmento-Sn Joquin Delt. During the summer months in typicl wter yer, the lower 36 km of the river chnnel is dry due to the lowering of the wter tble from municipl nd griculture wter demnds (Fleckenstein et l. 2004). The mjority of the lower river is leveed with the exception of sections in the lowest 5 km of the river within the 18,615 h Cosumnes River Preserve (CRP) mnged by The Nture Conservncy nd multiple government gencies. Within the CRP, four intentionl breches in the levee llow connection between the river nd its floodplin. The breches re prt of project tht hs restored former frmlnd to vrious floodplin hbitts through ctive nd pssive pproches (Swenson et l. 2003). The floodplin hbitt includes terrestril herbceous vegettion, ephemerl ponds, permnent ponds nd forest. Wter flows into the floodplin through four breches nd exits the floodplin through one smll brech nd slough used in summer s source of wter for locl frm (Figure 1). Enclosure Fish Growth Study For two flood sesons (2004 nd 2005), six enclosures were plced in ech of three different hbitt types in the floodplin nd two loctions in the river (Figure1). Floodplin hbitts were n ephemerl pond, flooded terrestril herbceous vegettion,

5 nd previously permnent pond. The ephemerl pond becme completely dry by lte summer nd supported nnul grsses nd other herbceous vegettion. It becme flooded when river flows incresed s result of rins in lte December or erly Jnury. The flooded uplnd vegettion ws in the re surrounding the ephemerl pond. It ws covered with nnul herbceous vegettion interspersed with some young ok, willow nd cottonwood trees. The lower pond ws connected to slough tht hd temporry dm cross it so wter could be pumped from it for irrigtion. As the slough elevtion ws rised during the summer months, the elevtion of the pond ws subsequently rised. This creted pond with fine, muddy, noxic substrte nd very little rooted vegettion. During the second yer of the study, the hydrologic connection between the lower pond nd the griculturl slough ws closed nd the pond dried out during the summer months, llowing grsses nd other herbceous vegettion to grow in the bottom of the pond. Thus, the vegettion chrcteristics of this pond differed between yers. The river loctions were the river chnnel bove the floodplin nd the river chnnel below the floodplin. The river loction bove the floodplin ws in non-tidl portion of the river with sndy substrte under bridge. The river loction below the floodplin ws in n freshwter tidl re, with substrte of smll grvel from nerby bridge butment nd fine muddy sediment. Enclosures in the river below the floodplin were plced in edge hbitt, which is similr to hbitt tht is generlly selected by juvenile Chinook slmon during migrtion (Beechie et l. 2005). We obtined pproximtely 0 juvenile Chinook slmon in Februry 2004 nd 2005 from the Mokelumne River Fish Htchery nd plced them in 142-liter cooler filled with wter from the htchery rcewy. An ertor ws plced in the cooler to

6 mintin dissolved oxygen levels. The fish were trnsported to the Cosumnes River Preserve where they were plced into 0.6m x 0.6m x 1.2m. The frmes of the enclosures were constructed from 19 mm polyvinyl chloride (PVC) pipe with 6.3 mm extruded plstic netting fitted round the frme. The 6.3mm netting llowed the free movement of zooplnkton, lrvl fish nd other food items to enter the enclosure. The netting ws held in plce by plstic cble ties plced t regulr intervls to keep the netting close to the frme. At ech loction, fish were hphzrdly selected by sweeping net through the cooler. Ten fish were selected nd their fork length mesured. After the fish were plced in the enclosure, cinder block ws tied with rope to the outside corner of the enclosure to keep it from floting wy. Then the remining opening in the netting ws closed using plstic cble ties. The enclosure ws plced on the substrte with its longest prt horizontl to the ground. The depth of wter t the cges vried with chnges in river flows. The cges were within meter of the wter surfce during ll but the highest flows. The cges in the ephemerl pond nd lower pond were in similr depths throughout the study. Due to vribility in river flows, fish smpling occurred when conditions llowed for enclosure loction nd retrievl. During high flows, high wter depth nd velocity did not llow ccess to the enclosure loctions. In flood seson 2004, the first yer of the study, fork lengths were mesured 17, 28 nd 32 dys fter initil deployment of the enclosures. Weights were only mesured on the initil deployment nd the finl dy of the experiment to reduce stress on the fish. Ech time fish were mesured, they were tken out of the enclosure, mesured nd then plced into n erted cooler until ll fish

7 were mesured. They were then plced bck into the enclosure nd the enclosure ws closed with cble ties. The lst time tht the fish were mesured, they were weighed nd then killed by quick blow to the hed nd plced in cooler with dry ice. In flood seson 2005, second yer of the study, fork lengths were mesured 6, 19, 41 nd 56 dys fter the initil deployment of the enclosures. Weights were not tken so tht fish would be hndled s little s possible. Temperture dt ws recorded using Onset stowwy tidbit temperture loggers. Flow dt ws obtined from the Michign Br strem flow guging sttion operted by the United Sttes Geologicl Survey. The Michign Br guge is locted km upstrem of the study site. River dischrge dt ws collected every 15 minutes throughout the length of the study. When dischrge t Michign Br reched 22.6 m 3 s -1, the river nd floodplin becme hydrologiclly connected. We nlyzed differences in fish length between hbitts using one-wy nlysis of vrince (ANOVA). Tukey-Krmer honestly significnt difference (HSD) tests were preformed to determine which hbitts showed significnt differences in lengths t the intervls tht fish were smpled. ANOVA nd Tukey-Krmer tests were ssessed for significnce t =.05. Results Physicl prmeters In 2004, slmon were plced on the floodplin while it ws connected with the river nd during the descending limb of smll flood (45 m 3 s -1 ) on 20 Februry. A week fter the fish were plced in the enclosures, the lrgest flood (108 m 3 s -1 ) of the yer occurred. The

8 river nd floodplin remined hydrologiclly connected for 14 dys from the time the enclosures were deployed nd were disconnected for the finl 19 dys of the study (Figure 2). As the floodplin drined, wter levels decresed t some enclosure loctions. As the wter stge lowered nd ir tempertures incresed the temperture of the wter on the floodplin lso incresed (Figure 4). In 2005, slmon were plced on the floodplin 5 dys fter pek flow ( m 3 s -1 ) on 25 Februry. The floodplin becme disconnected from the river, nd hd begun drining by the time the enclosures were deployed. Smll floods mintined hydrologic connection between the river nd the floodplin for the next 23 dys. On dy 24, flows incresed to 368 m 3 s -1 nd the floodplin remined connected to the river for the remining 30 dys of the study (Figure 3). The tempertures on the floodplin incresed during the stble flows in the river fter the lrge flow event (Figure 4). Fish Growth In 2004, the length of the fish ws the sme for ll of the enclosures t the initil deployment (55.0 ± 0.6 mm; ANOVA: p=0.95; Figure 5). The first time tht the enclosures were checked, fter 17 dys, the verge lengths of the fish in the flooded vegettion site nd the ephemerl pond were significntly greter thn those of fish in the other 3 loctions (ANOVA: p<0.0001; Tukey-Krmer HSD: P<0.05, q=2.75) (Figure 2). The second time tht the enclosures were smpled, fter 26 dys, fish in the flooded vegettion site nd the ephemerl pond were still significntly longer thn those in the lower pond nd the river loction below the floodplin (ANOVA: p<0.0001; Tukey- Krmer HSD: P<0.05, q=2.76). However, lengths of fish in the river site bove the

9 floodplin incresed rpidly nd were intermedite between the two floodplin hbitts nd the lower pond nd river loction below the floodplin (Figures 2 nd 4). The finl time tht the fish were smpled, 32 dys fter deployment, the fish in the river site upstrem of the floodplin were sttisticlly grouped with the fish in the ephemerl floodplin sites, with longer lengths thn the fish in the lower pond nd the river below the floodplin. (ANOVA: p<0.0001; Tukey-Krmer HSD: P<0.05, q=2.76; Figure 5). In 2005, the men fork length of the fish ws the sme for ll enclosures t the initil deployment (54.2 ± 0.2 mm; ANOVA: p=0.89; Figure 6). When the fish were plced in enclosures 1 nd 2 of the flooded vegettion site, they immeditely displyed errtic operculr movements nd swm rpidly in circles. Within 5 minutes, ll of the fish plced in the enclosures were ded. A concurrent wter qulity study indicted tht the dissolved oxygen levels in the re hd dropped from three dy men of 60% sturtion (6.2 Mg L -1 ) to pproximtely 30% sturtion (3.0 Mg L -1 ) two dys prior to the fish being plced in the enclosures (Ahern et l. in press). The enclosures were moved to loction closer to the center of the floodplin nd ten more fish were plced in ech enclosure. Eleven of the fish in this loction survived for eleven dys, nd then ll of the fish died on 3 Mrch, most likely due to low dissolved oxygen levels. The lengths of the fish tht died s result of low dissolved oxygen were not used in the nlysis of growth rtes between hbitts. Due to high wter levels in the river, the first time tht the enclosures were checked ws seven dys fter the initil deployment nd only the enclosures on the floodplin could be ccessed. The fish in the lower pond showed slower growth thn fish in the ephemerl pond nd submerged herbceous vegettion. The first time tht ll of the loctions were smpled, 20 dys fter initil deployment, the

10 fish in the terrestril vegettion, ephemerl pond nd bove the floodplin showed growth tht ws significntly higher thn tht of fish in the lower pond nd below the floodplin (ANOVA: p<0.0001; Tukey-Krmer HSD: P<0.05, q=2.75; Figures 3 nd 5). We were unble to smple the fish gin for 22 dys, 41 dys fter initil deployment, due to the high dischrge in the river. The enclosures in the river bove the floodplin hd no fish in them. The enclosures were ll structurlly sound nd four were prtilly buried in snd. It is likely tht the fish perished from the effects of suspended prticles during the previous high flow event. The fish in ll three hbitts on the floodplin showed high growth reltive to fish in the river below the floodplin, which showed little growth from the previous smpling (ANOVA: p<0.0001; Tukey-Krmer HSD: P<0.05, q=2.60; Figure 6). The finl smpling took plce fter 56 dys. The fish in ll three of the floodplin hbitts continued to grow with similr growth rtes. Fish in the river below the floodplin did show n increse in length, but length reltive to floodplin fish ws still smll (Figures 3, 5 nd 6). Discussion Juvenile Chinook slmon plced in ephemerl floodplin hbitts grew more thn fish plced in the intertidl river site below the floodplin; these results were similr to those found by Sommer et l. (2001) (Figure 7). The river site bove the floodplin showed reltively high growth during the first yer of the study, but ws lethl to the fish during high flow events in the second yer (Figure 5). Sommer et l. (2001) suggested tht incresed growth on the floodplin ws result of higher tempertures nd higher

11 productivity reltive to the djcent min-stem river hbitt. Our findings suggest tht long with incresed temperture nd productivity, flooded terrestril herbceous vegettion is lso importnt for incresed growth of juvenile slmon throughout vriety of flow conditions. During the first yer of the study, fish in the lower pond showed slower growth rtes reltive to those in other floodplin sites, but growth rtes were similr to those found in the river site below the floodplin. The lower pond hd filled 9 yers erlier nd remined wet the entire time. During the 9 yers of inundtion, no vegettion hd grown in the pond. After the first yer of the study, the lnd mngers closed the gte tht connected it with slough used s source of wter for irrigtion, resulting in the pond drying out nd herbceous vegettion growing in the substrte. Grsses nd cockleburs were the predominnt plnts, similr to the ephemerl pond. During the second yer of the study, fish in this pond re showed significntly higher growth rtes thn those in the river site below the floodplin (Figure 6). This is presumbly becuse of the bundnt zooplnkton tht formed mjor prt of the slmon diet (unpublished dt). Other studies hve shown tht in floodplin hbitts, zooplnkton bundnce nd biodiversity re closely ssocited with vegettion (Brnyi et l. 2002). Temperture is n importnt physicl prmeter tht influences the growth of juvenile Chinook slmon on floodplins (Sommer et l. 2001). Tempertures from 14 0 C to 19 0 C hve been shown to provide optiml growing conditions for juvenile Chinook slmon fed t 60% to 80% of stition (Mrine nd Cech 2004; Richter nd Kolmes 2005). The optimum temperture for growth is dependnt on the mount of food tht is vilble to juvenile slmon. In hbitts where food is bundnt nd fish re stited,

12 tempertures for optimum growth my be higher thn those observed in studies where food is limited (Myrick nd Cech 2004). Tempertures on the floodplin reched dily mximum of 25 0 C nd fish continued to grow rpidly. The continued growth t high tempertures implies tht food is not limited during wrm tempertures. Higher temperture is one of the fctors tht distinguish the floodplin hbitt from the river hbitt (Figure 4). When the river stge is high nd the floodplin nd river re hydrologiclly connected, there is little difference in tempertures between the floodplin nd the river hbitts. When flows re lower or the river is not connected with the floodplin, tempertures on the floodplin re wrmer thn those of the river (Figure 4). The differences in temperture closely trck the observed differences in growth noted mong the different hbitts used in the study. Mgnitude nd durtion of flows tht enter the floodplin re fctors tht drive primry production on the floodplin (Ahern et l. in press). At high flows, the floodplin crries the mjority of flow tht comes down the river. During these high flow events, wter chemistry is virtully identicl on the floodplin nd river. Due to the reltively lrge surfce re nd bundnt vegettion, velocities re much lower on the floodplin, which provides refuge for fish nd other fun moving down the river. It is not until flows in the river begin to subside tht wter on the floodplin looses velocity completely. As the wter velocity on the floodplin is reduced, wter begins to cler s suspended sediments fll from the wter column. As the wter level lowers nd clers, it wrms (Figure 4), creting idel conditions for the growth of phytoplnkton (Ahern et l. in press), s well s for zooplnkton nd other nimls tht feed on phytoplnkton.

13 These periods of floodplin river disconnection provide the best growing conditions for juvenile Chinook slmon on the Cosumnes river floodplin. Fish plced in the chnnel bove the floodplin in the first yer of the study showed vrying growth depending on mgnitude of river flows. When flows were high nd turbid, fish showed similr growth to those in the intertidl chnnel site below the floodplin, which ws significntly lower thn growth observed in the ephemerl floodplin. When river flows were low nd wter cler, fish in the chnnel bove the floodplin showed similr growth to fish in the ephemerl floodplin. Fish in the intertidl chnnel below the floodplin showed slow growth throughout both yers of the study, with no correltion to river dischrge. Wter in the river site below the floodplin remined cold nd turbid throughout the study nd chnged very little with river dischrge. In the second yer of the study, fish in the chnnel bove the floodplin grew rpidly during the first prt of the study, when flows were low nd cler. Flows in the river then incresed nd remined high nd turbid for the reminder of the study. There ws 100% mortlity rte for fish in the river site bove the floodplin during high dischrges. The fish most likely died becuse there ws no escpe from high velocities where the enclosures were locted. During high flow events, wild slmon migrting downstrem would not be ble to rer in the incised min chnnel, but would likely rer in the restored floodplin, where rering conditions re fvorble, or intertidl hbitt where rering conditions re less fvorble. This shows the importnce of off-chnnel rering hbitt for juvenile slmon during high flow conditions. Likewise, periods of wter stgntion on floodplins cn lso crete conditions lethl to enclosed fish due to low dissolved oxygen. These dt show how vrible single hbitt cn be depending

14 on chnging physicl conditions. Nturl floodplins tend to be heterogeneous in terms of wter qulity, nd during stressful conditions, fish will seek out more fvorble physicl conditions for rering (Mtthews nd Burg 1997, Ahern et l. in press). Restortion of floodplins nd other off chnnel hbitts is potentilly importnt for incresing production of juvenile slmonids in centrl Cliforni. When juvenile slmon re migrting down from upstrem spwning grounds during high flow events, migrtion is more pssive thn ctive (Heley 1980; Kjelson et l. 1981). Juvenile fish re essentilly entrined in the wter column until they find slower wter velocities where ctive swimming becomes possible. The Cosumnes river is highly incised nd chnnelized upstrem of the restored floodplin, which is directly bove the tidlly influenced portion of the river. During ll but the highest flow events, fish migrting downstrem hve little ccess to off-chnnel or floodplin hbitt until they rech the restored floodplin in the lst five km before the river becomes tidl. Fish in the river bove the floodplin showed highest growth rtes when wter conditions were low nd cler. However, when dischrge ws high, fish in the chnnelized portion of the river bove the floodplin showed decresed growth rtes nd high mortlity. Juvenile Chinook slmon in our study lso showed slow growth in the tidl fresh wters below the floodplin. Overll, our study suggests tht if more off chnnel floodplin hbitt were vilble to juvenile Chinook during downstrem migrtion, fish would be lrger when they reched esturine nd mrine wters, which hs been found to increse overll survivorship (Unwin 1997; Glt nd Zweimuller 2001).

15 Figure 1. Loction of the studied hbitt types (solid circle).

16 Figure 2. Men length (+/- SE) of juvenile Chinook slmon in vrious hbitts plotted with river dischrge during 2004 smpling seson. Tri Veg = flooded terrestril vegettion, Tri Pond = ephemerl pond, Lower pond = permnent pond during the first yer nd ephemerl pond in the second yer, Below FP = intertidl river chnnel below restored floodplin, Above FP = min-stem river chnnel bove floodplin. 90 Tri Veg Tri Pond Lower pond Below FP Above FP Dischrge Flood stge Length (mm) Dischrge (cms) 55 2/18/04 2/23/04 2/28/04 3/4/04 3/9/04 3/14/04 3/19/04 3/24/04 0

17 Figure 3. Men length (+/- SE) of juvenile Chinook slmon in vrious hbitts plotted with river dischrge during 2005 smpling seson. See figure 2 for hbitt descriptions. Tri Veg Tri Pond Lower Pond Below FP Above FP Dischrge Flood stge Length (mm) Dischrge (cms) /22/2005 3/4/2005 3/14/2005 3/24/2005 4/3/2005 4/13/2005 4/23/2005

18 Figure 4. Wter temperture of floodplin (drk line) nd river (light line) in reltion to river dischrge (dshed line) in 2004 () nd 2005 (b). ) Degrees Celsius Dischrge (cms) b) 5 2/19/04 2/29/04 3/10/04 3/20/ Degrees Celsius Dishchrge (cms) 5 2/25/05 3/7/05 3/17/05 3/27/05 4/6/05 4/16/05 0

19 Figure 5. Length of juvenile slmon in vrious loctions in Different letters denote significnt differences in length (Tukey-Krmer HSD: P<0.05, q=2.76,). See figure 2 for hbitt descriptions Length (mm) Length (mm) b b b Tri veg Tri pond Low er pond Above FP Below FP Tri veg Tri pond Low er pond Above FP Below FP Length (mm) c b c Length (mm) b b Tri veg Tri pond Low er pond Above FP Below FP Tri veg Tri pond Low er pond Above FP Below FP

20 Figure 6. Length of juvenile slmon in vrious loctions in Different letters denote significnt differences in length (Tukey-Krmer HSD: P<0.05, q=2.59,). See figure 2 for hbitt descriptions Length (mm) Length (mm) b b Tri Veg Tri Pond Low er Pond Below FP Above FP Tri Veg Tri Pond Low er Pond Below FP Above FP Length (mm) b c d Length (mm) b c d Tri Veg Tri Pond Lower Pond Below FP Above FP Tri Veg Tri Pond Low er Pond Below FP Above FP

21 Figure 7. Comprison of single cge of fish rered in intertidl river hbitt below floodplin (left) nd single cge of fish rered in the tringle vegettion (right) fter 54 dys in respective hbitts.

22 Bibliogrphy Brnyi, C., T. Hein, C. Holrek, S. Keckeis, nd F. Schiemer Zooplnkton biomss nd community structure in Dnube River floodplin system: effects of hydrology. Freshwter Biology 47(3): Byley, P The Flood Pulse Advntge nd the Restortion of River-Floodplin Systems Regulted Rivers Reserch & Mngement 6(2): Beechie, T. J., M. Liermnn, E. M. Bemer, nd R. Henderson A clssifiction of hbitt types in lrge river nd their use by juvenile slmonids. Trnsctions of the Americn Fisheries Society 134(3): Brown, T. G., nd G. F. Hrtmn Contribution of Sesonlly Flooded Lnds nd Minor Tributries to the Production of Coho Slmon in Crntion Creek, British- Columbi. Trnsctions of the Americn Fisheries Society 117(6): CALFED Ecosystem Restortion Multi-Yer Progrm Pln (Yers 5-8). Fleckenstein, J., M. Anderson, G. Fogg, nd J. Mount Mnging surfce wtergroundwter to restore fll flows in the Cosumnes River. Journl of Wter Resources Plnning nd Mngement-Asce 130(4): Florsheim, J. L., nd J. F. Mount Restortion of floodplin topogrphy by sndsply complex formtion in response to intentionl levee breches, Lower Cosumnes River, Cliforni. Geomorphology 44(1-2): Glt, D. L., nd I. Zweimuller Conserving lrge-river fishes: is the highwy nlogy n pproprite prdigm? Journl of the North Americn Benthologicl Society 20(2): Heley, M. C Utiliztion of the Nnimo River estury by juvenile chinook slmon, Oncorhynchus tshwytsch. Fishery Bulletin 77: Junk, W. J., P. B. Byley, R. E. Sprks The flood pulse concept in river-floodplin systems. Specil publiction Cndin Journl of Fisheries nd Aqutic Sciences 106: Kjelson, M. A., P. F. Rquel, nd F. W. Fisher The Life-History of Fll Run Juvenile Chinook Slmon, Oncorhynchus-Tshwytsch, in the Scrmento Sn Joquin Estury of Cliforni. Esturies 4(3): Mrine, K. R., nd J. J. Cech Effects of high wter temperture on growth, smoltifiction, nd predtor voidnce in Juvenile Scrmento River Chinook slmon. North Americn Journl of Fisheries Mngement 24(1):

23 Mtthews, K. R., nd N. H. Berg Rinbow trout responses to wter temperture nd dissolved oxygen stress in two southern Cliforni strem pools. Journl of Fish Biology (1):-67. Mount, J. F Cliforni Rivers nd Strems. University of Cliforni Press, Berkeley. Myrick, C. A., nd J. J. Cech Temperture effects on juvenile ndromous slmonids in Cliforni's centrl vlley: wht don't we know? Reviews in Fish Biology nd Fisheries 14(1): Pollock, M. M., G. R. Pess, nd T. J. Beechie The importnce of bever ponds to coho slmon production in the Stillgumish River bsin, Wshington, USA. North Americn Journl of Fisheries Mngement 24(3): Richter, A., nd S. A. Kolmes Mximum temperture limits for chinook, coho, nd chum slmon, nd steelhed trout in the Pcific Northwest. Reviews in Fisheries Science 13(1): Richter, B. D., R. Mthews, nd R. Wigington Ecologiclly sustinble wter mngement: Mnging river flows for ecologicl integrity. Ecologicl Applictions 13(1): Sommer, T. R., M. L. Nobrig, W. C. Hrrell, W. Bthm, nd W. J. Kimmerer Floodplin rering of juvenile chinook slmon: evidence of enhnced growth nd survivl. Cndin Journl of Fisheries nd Aqutic Sciences 58(2): Swenson, R. O., K. Whitener, nd M. Eton Restoring floods on floodplins: riprin nd floodplin restortion t the Cosumnes River Preserve.. Pges in P. M. Fber, editor Cliforni Riprin Systems: Processes nd Floodplins Mngement, Ecology, nd Restortion Riprin Hbitt nd Floodplins Conference Proceedings. Riprin Hbitt Joint Venture. Riprin Hbitt Joint Venture, Scrmento, CA. Tockner, K., nd J. A. Stnford Riverine flood plins: present stte nd future trends. Environmentl Conservtion 29(3): Unwin, M. J Fry-to-dult survivl of nturl nd htchery-produced chinook slmon (Oncorhynchus tshwytsch) from common origin. Cndin Journl of Fisheries nd Aqutic Sciences 54(6): Wurtsbugh, W. A., nd G. E. Dvis Effects of Temperture nd Rtion Level on Growth nd Food Conversion Efficiency of Slmo-Girdneri, Richrdson. Journl of Fish Biology 11(2):87-98.