Influence of elevated CO2 on the early life history of Euphausia pacifica and Calanus pacificus
Presentation Abstract
Despite the ecological importance of crustacean zooplankton there is little knowledge about how their populations will be affected by ocean acidification. The copepod Calanus pacificus and the krill Euphausia pacifica are two dominant crustacean zooplankton that are important prey species in the food webs of Puget Sound and the North Pacific. We currently observe pCO2 levels of 1600 μatm in bottom waters of several areas of Puget Sound and concentrations of 2400 μatm have been observed in southern Hood Canal. These high CO2 levels are the result of both anthropogenic and natural processes but the temporal and spatial extent of high CO2 waters are expected to expand as atmospheric CO2 concentration increases. In this study we spawned C. pacificus and E. pacifica at different pCO2 levels and monitored their hatching success and development of the early life stages which are likely to be most vulnerable to stress. Our preliminary results show that egg hatching in E. pacifica is robust to increased pCO2 across the range of 400-3200 μatm pCO2. However, the proportion of hatched nauplii that develop to the first feeding stage over seven days is significantly reduced at pCO2 levels of 1600 μatm and greater. Egg hatching in C. pacificus is reduced at 2400 μatm pCO2 while the proportion of nauplii that reach the first feeding stage over four days is reduced, but only at high (3200 μatm) pCO2. Further work on C. pacificus at less extreme pCO2 concentrations is needed to resolve the pCO2 level where hatching begins to be affected. These data suggest that E. pacifica populations may be more vulnerable to ocean acidification than those of C. pacificus and its development is significantly slowed at CO2 concentrations that are currently observed in the bottom waters of Hood Canal. Because development rate significantly affects survival to adult, acidification has the potential to influence krill populations and impact the food webs of the Salish Sea.
Session Title
Session S-05A: Frontiers of Ocean Acidification Research in the Salish Sea
Conference Track
Ocean Acidification
Conference Name
Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)
Document Type
Event
Start Date
1-5-2014 10:30 AM
End Date
1-5-2014 12:00 PM
Location
Room 615-616-617
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Euphausia pacifica--Effect of water acidification on--Washington (State)--Puget Sound; Copepoda--Effect of water acidification on--Washington (State)--Puget Sound; Carbon cycle (Biogeochemsitry)--Washington (State)--Puget Sound; Ocean acidifcation--Washington (State)--Puget Sound
Geographic Coverage
Salish Sea (B.C. and Wash.); Puget Sound (Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Influence of elevated CO2 on the early life history of Euphausia pacifica and Calanus pacificus
Room 615-616-617
Despite the ecological importance of crustacean zooplankton there is little knowledge about how their populations will be affected by ocean acidification. The copepod Calanus pacificus and the krill Euphausia pacifica are two dominant crustacean zooplankton that are important prey species in the food webs of Puget Sound and the North Pacific. We currently observe pCO2 levels of 1600 μatm in bottom waters of several areas of Puget Sound and concentrations of 2400 μatm have been observed in southern Hood Canal. These high CO2 levels are the result of both anthropogenic and natural processes but the temporal and spatial extent of high CO2 waters are expected to expand as atmospheric CO2 concentration increases. In this study we spawned C. pacificus and E. pacifica at different pCO2 levels and monitored their hatching success and development of the early life stages which are likely to be most vulnerable to stress. Our preliminary results show that egg hatching in E. pacifica is robust to increased pCO2 across the range of 400-3200 μatm pCO2. However, the proportion of hatched nauplii that develop to the first feeding stage over seven days is significantly reduced at pCO2 levels of 1600 μatm and greater. Egg hatching in C. pacificus is reduced at 2400 μatm pCO2 while the proportion of nauplii that reach the first feeding stage over four days is reduced, but only at high (3200 μatm) pCO2. Further work on C. pacificus at less extreme pCO2 concentrations is needed to resolve the pCO2 level where hatching begins to be affected. These data suggest that E. pacifica populations may be more vulnerable to ocean acidification than those of C. pacificus and its development is significantly slowed at CO2 concentrations that are currently observed in the bottom waters of Hood Canal. Because development rate significantly affects survival to adult, acidification has the potential to influence krill populations and impact the food webs of the Salish Sea.
