Foraging  and  growth  poten/al  of  juvenile  Chinook  salmon  following  /dal  restora/on  of  the  Nisqually  River  delta.  

September  20,  2013  

Aaron  David1,  Christopher  Ellings2,  Isa  Woo3,  Charles  Simenstad1,  Kelley  Turner3,  John  Takekawa3,    

Ashley  Smith3,  and  Jean  Takekawa4  

1University  of  Washington,  School  of  Aqua/c  and  Fishery  Sciences  2Nisqually  Indian  Tribe,  Department  of  Natural  Resources  3U.S.  Geological  Survey,  Western  Ecological  Research  Center  4U.S.  Fish  and  Wildlife  Service,  Nisqually  Na/onal  Wildlife  Refuge  

Acknowledgements  Jesse  Barham  Walker  Duval  MaS  Holt  

Emiliano  Perez  Lisa  Belleveau  Caitlin  Guthrie  Jus/n  Hall  Ben  Ryken  

Peter  Markos  Sam  Stepe/n  Kyle  Kautz  

Eddie  Villegas  Tom  Friedrich  

The  Wetland  Ecosystem  Team  And  many  others…  

Cartography  by  Amy  Calahan  

Funding:  US  EPA,  Nisqually  Tribe,  US  Fish  and  Wildlife  Service,  NSF  Graduate  Research  Fellowship  Program  

Photo:  Michael  Grilliot  

Nisqually  River  Estuary,  Fall  2009  

Ques/on:  Do  restored  and  reference  marshes  provide  equivalent  growth  opportuni/es  for  juvenile  Chinook  salmon?  

Growth  is  primarily  a  func/on  of:  -­‐  The  amount  of  prey  consumed  -­‐  The  energe/c  quality  of  prey  consumed  -­‐  The  temperature  regime  experienced  by  a  consumer  

Tidal  channel  reconnected  in  2009   Unaltered,  reference  /dal  channel  

Diet  analysis  

Fyke  trap  ne`ng    

Consump/on  rate  study   Temperature  loggers  

Bioenerge/cs  model  

Bioenerge/cs  model  

Growth  =  Consump/on  –  (Metabolism  +  Wastes)  

Inputs:  •  Consumer  mass        •  Consump/on  rate  •  Prey  energy  density  •  Consumer  energy  density  •  Temperature  

Results:  Chinook  salmon  densi/es  

Results:  Diet  composi/on  

Results:  Diet  energy  density  

Results:  Stomach  fullness  

Results:  Temperatures  

Results:  2010  Growth  

Results:  2011  Growth  

Results:  2012  Growth  

Photo:  Jean  Takekawa  

Conclusions:  •  Our  findings  are  generally  consistent  with  other  

studies  of  estuary  restora/on  projects  

•  The  reconnected  habitats  appear  to  provide  similar,  but  more  variable  opportuni/es  for  Chinook  growth  

•  Increased  sensi/vity  to  air  temperatures  may  limit  the  growth  value  of  these  habitats  when  temperatures  are  warm  

Es/ma/ng  Chinook  daily  consump/on  for  each  sampling  event  

•     

Number  of  hours  in  a  day  

Gastric  evacua/on  rate  

Mean  stomach  fullness  over  the  whole  day  

Mean  stomach  fullness  at  the  beginning  and  end  of  the  24  hour  period  

Results:  Consump/on  study