Ocean Acidification: Biological Impacts and Research

Robert Foy and Tom Hurst2014 AOOS Ocean Acidification Workshop

Linking Knowledge to Need: Responding to Ocean Acidification (OA) in Alaska

Alaska Fisheries Science Center

December 2, 2014

NOAA Alaska Fisheries Science Center Research Approach

Focal species groups• Commercially important fish and shellfish species; • Their prey (calcareous plankton);• And shelter (corals).

Objectives•Ocean pH monitoring•Understand species-specific physiological responses;•Forecast population impacts and economic consequences.

King and Tanner Crab Research

2006-2007 pilot experiments: effects of pH change on growth and survival of blue king crab.

2008 AFSC ocean acidification research plan

2008-2009 methods development: —water chemistry and mineral measurement method development—effective CO2 delivery system designed for red king crab—Additional response variables

2010-2013 experimentation: —Red king crab larval growth and survival response to increased pCO2

—Golden king crab adult physiological response to increased pCO2

—Tanner crab larval and adult response to increased pCO2

W. Christopher Long, Katherine M. Swiney, and Robert J. Foy

• Long, Swiney, Foy. 2013. Effects of Ocean acidification on embryos and larvae of red king crab, Paralithodes camtschaticus. Marine Pollution Bulletin. 69: 38-47.

• Long, Swiney, Harris, Page, Foy. 2013. Effects of ocean acidification on juvenile red king crab (Paralithodes camtschaticus) and Tanner crab (Chionoecetes bairdi). PLoS ONE 8(4).

red king crab (Paralithodes camtschaticus)

blue king crab (Paralithodes platypus)

golden king crab (Lithodes aequispinus)

King and Tanner Crab Research

• Important shell (cuticle) components are chitin, calcium carbonate and protein

• Calcium carbonate occurs mainly as calcite although the amorphous form sometimes occurs

Why Crab??

Depth distributions

Life Stage Intertidal Subtidal Middle Outer Upper Lower Upper LowerRed King Crab Mature 3-300

Juvenile 0-200Larval 0-100Egg 0-200

Blue King Crab Mature 0-200Juvenile 0-200Larval 0-100Egg 0-100

Golden King Crab Mature 100-1000Juvenile >1000Larval 200-1000Egg 100-1000

CanyonSlopeShelf

As depth increases: (pressure increases, temperature decreases, and pH decreases) – all of which promote the dissolution of CaCO3.

Affected by pH?

Affected by CaCO3 saturation state?

King and Tanner Crab Research

Experiments: Red king crab (Paralithodes camtschaticus) adult females

Red king crab embryos and larvae

Red king crab juveniles

Tanner crab (Chionoecetes bairdi) juveniles

Golden king crab (Lithodes aequispinus) adults

Response variables: Survival, fecundity, morphometrics (image analysis), growth (width and wet mass), calcification

Treatment system:• Flow through CO2 delivery system

• pH control

• Daily pH, temperature, and salinity measurement

• Weekly water samples taken for DIC and Alkalinity

King and Tanner Crab Research

Kodiak Fisheries Research Center Seawater FacilityOA Treatment system:• Open, flow through CO2 delivery system• 2 L/min – 10 L/min• Current capability: 1 control, 4 CO2 treatments• In construction: 2 controls, 8 CO2 treatments, 3 temperature

treatments, variable control• pH control

• Daily pH, temperature, and salinity measurement

• Weekly water samples taken for DIC and Alkalinity

Red King Crab Embryos• Adult females collected from Bristol Bay fishery• pHs: Ambient and 7.7 (~2100)• Decreased pH associated with smaller eggs and

embryos and larger yolks.

• Larvae collected as they hatched• Starvation survival experiments fully

crossed with “mom” treatments• 5 replicates with 20 larvae• pHs: ambient and 7.7

• Calcification increased • Morphometrics varied• Survival decreased

Red King Crab Larvae

Day

0 5 10 15 20 25

Mo

rtal

ity

0.0

0.2

0.4

0.6

0.8

1.0 AAACCACCAA AC CA CC

control “mom” and control larvae

acidified “mom” and acidified larvae

Embryonic treatment

Control Acidified

Per

cen

t C

a (

m/m

)

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

InitialControlAcidified

a

bc

a

bc

Larval treatment

• Crabs held in individual containers• Control, pH 7.8, pH 7.5• 30 crabs/treatment• Check for molts/mortalities• Measure pH/temp• Growth (length and mass) reduced• Calcium content did not change

Red King Crab Juveniles

Control pH 7.8

Co

nd

ition

ind

ex

120

140

160

180

200

220

Control pH 7.8

% C

alc

ium

(dry

ma

ss

)10

12

14

16

18

20

Car

apac

e le

ng

th (

mm

)

2.0

2.5

3.0

3.5

4.0

4.5ControlpH 7.8ControlpH 7.8

Degree days

0 250 500 750 1000 1250 1500 1750

Wet

mas

s (g

)

0.01

0.02

0.03

0.04

0.05

0.06

a

b

Tradeoff?

Days

0 50 100 150 200

Pe

rce

nt s

urv

iva

l

0

20

40

60

80

100ControlpH 7.8pH 7.5

• Crabs held in individual containers• Control, pH 7.8, pH 7.5• 30 crabs/treatment• Survival decreased with decreasing pH

Red King Crab Juveniles

Bristol Bay red king crab fishery:•OA scenarios based on trends in recruitment •Forecasts based on bioeconomic model linked to a population dynamics model

King Crab Population Effects

UAF

USCG

Michael Dalton, Andre Punt

stock dynamics without OAKing Crab Population Effects: Red King Crab

• At a pH of 7.8 stocks and catches decline

• Under current catch levels fishery would be closed in about 2100

• Punt, Poljak, Dalton, Foy. 2014. Evaluating the impact of ocean acidification on fishery yields and profits: The example of red king crab in Bristol Bay. Ecological Modeling. 285: 39-53.

stock dynamics with OA

Ocean Acidification outreachOcean Acidification outreachKodiak Fisheries Research Center Ocean Science Discovery LabOcean Science Discovery Lab

NMFS and Kodiak Island Borough School District collaboration

Goal: to improve Ocean Science LiteracyOcean Science Literacy in grades K -12

• Middle School: What is OA? How do you measure ocean pH?• Intro to pH scale and ocean chemistry• Algal growth and plankton exposure

experiments

• High School: HS Oceanography class• Local OA background• Global OA implications• Climate change

Thank you. Questions?

WWW.AFSC.NOAA.GOV

• Alaska Fisheries Science Center Research Staff