Mackenzie Gavery's Presentation at PCSGA

1. Pacific Oysters and
Ecosystem Health
Mackenzie Gavery
University of Washington
School of Aquatic and Fishery Sciences

2. Pacific oysters as indicators of
Puget Sound health:
• Common, widely distributed
• Immobile with high site
fidelity
• Reasonably resistant to
contaminants
• Bioaccumulate at levels
relative to their environment

3. Pacific oysters as indicators of
Puget Sound health:
• Important to the region
• economically
• culturally
• socially

4. Outline
 Overview of PROPS
 Methods
 Data
 Next steps

5. PROPS: Physiological Response
of Oysters in Puget Sound
 Objectives
 Implement use of biomarkers to assess Puget Sound
ecosystem health
 Determine indirect biological effects of local stressors
 Characterize epigenetic impacts on shellfish

6. Methods: Site Selection
Level of concern:
High
Mid
Low
Pacific oyster populations:
natural set
commercially farmed
(outplanted juveniles)

7. Juvenile oyster siblings
40
35
A *
B
30
shell length (mm)
25
20
15
10
5
0
Low Mid High
T=0 Willapa Bay Samish North Bay
June August
Bay

8. Methods: Sampling
 Adults (n=20)
 size
 gill tissue
 hemolymph

9. Methods: Water Quality Data
 WA State Department of Health
 Department of Ecology
 University of Washington
Site A: Drayton Harbor (WA DOH)
40 1000
Fecal Coliform (FC/100mL)
900
Temp (ºC) / Salinity (ppt)
35
Salinity 800
30
700
25 600
20 500
15 400
Temp 300
10
200
5 100
Fecal Coliform
0 0
Mar-07
Mar-11 Jun-07
Jun-11 Sep-07
Sep-11 Dec-07
Dec-11 Mar-08
Mar-12 Jun-08
Jun-12 Sep-08
Sep-12 Dec-08
Dec-12 Mar-09
Mar-13

10. Methods: Integrated Approach
 Gene expression
 Indirect biological effects – response to a
secondary stressor
 Epigenetic characterization

11. Methods: Integrated Approach
 Gene expression
 Indirect biological effects – response to a
secondary stressor
 Epigenetic characterization

12. Indirect biological effects
 Are current environmental conditions impairing the
ability of an organism to respond successfully to a
future stress?
 Applying a stress in the field and evaluating response:
 stress (mechanical) response (noradrenaline)
 a “normal” response is an increase in noradrenaline
after applying mechanical stress.

13. Noradrenaline: results
25
Low
noradrenaline (pg/mL)
20
15
10
5
0
1.4 pre- post-stress
1.2
noradrenaline (pg/mL)
Mid
1 High
0.8
0.6
0.4
0.2
0
pre- post-stress pre- post-stress

14. Methods: Integrated Approach
 Gene expression
 Indirect biological effects – response to a
secondary stressor
 Epigenetic characterization

15. Epigenetics
 Heritable changes in trait or phenotype, caused by a
mechanism other than mutation to the DNA sequence
 Most common epigenetic mechanism is DNA
methylation:
A
G
T
C
Me

16. Epigenetics
 Compounds that impact normal epigenetic functions:
 Endocrine disruptors
 estrogen
 BPA
 pesticides
 Effects of epigenetic disruptions:
 tumor promotion
 alteration of development
 inhibition of reproduction

17. Epigenetics:
DNA methylation analysis
extract DNA
 Whole genome DNA
methylation
quanitification bind DNA to
plate
 ELISA based
 Result is %
add antibody to
methylated DNA 5-me-cytosine
add secondary
enzyme

18. Epigenetics: Data
8
P = 0.03
estimated % DNA methylation
7.5
7
6.5
6
5.5
5
Site C
Low Site A
High

19. Summary
 Noradrenaline concentration following stress may be a
good candidate to evaluate indirect biological effects.
 Preliminary data show epigenetic variability between oyster
populations in Puget Sound.
 These methods have the potential to provide valuable
information on ecosystem health.

20. Acknowledgements
 Dr. Steven Roberts – UW, SAFS
 Samuel White – UW, SAFS
 Joth Davis - Taylor Shellfish Farms
 All the Volunteers