THE EFFECTS OF OCEAN ACIDIFICATION AND TEMPERATURE ON OYSTERS AND THE POTENTIAL OF SELECTIVE BREEDING TO AMELIORATE CLIMATE CHANGE

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1 University of Western Sydney THE EFFECTS OF OCEAN ACIDIFICATION AND TEMPERATURE ON OYSTERS AND THE POTENTIAL OF SELECTIVE BREEDING TO AMELIORATE CLIMATE CHANGE Laura Parker (PhD Candidate), Assoc. Prof. Pauline Ross and Dr Wayne O Connor University of Western Sydney, NSW Department of Primary Industries Australia

2 Money Climate change is expected to have impacts on marine organisms and ecosystems Twolia Economic consequences $$$ Jan-08 M ar -08 M ay-08 Jul -08 Sep-08 Nov-08 Jan-09 Time

3 BACKGROUND Elevations in atmospheric CO 2 : CO 2 CO 2 CO 2 CO 2 CO 2 Temperature of oceans rising Changing ocean chemistry Dissolves into the Ocean Lindberg 2008 Green Expander 2008 Ocean acidification

4 IF OCEANS ACIDIFY AND WARM Broadcast spawners such as molluscs, which release their gametes into the water column, may be affected from the beginning of their development

5 Few studies: PREVIOUS STUDIES: EGGS AND LARVAE Fertilisation (Kurihara et al. 2004; 2007, Havenhand et al. 2008) Size (Kurihara et al. 2004; 2007) Wim van Egmond 1995 Abnormality (Kurihara et al. 2004; 2007) Mortality (Yamada and Ikeda 2004) Synergistic impacts: Two Studies... (Parker et al. 2009; Byrne et al. 2009) Doyle ABC News 2008

6 AIM PART 1 To determine and compare the synergistic impacts of ocean acidification and temperature on embryos and larvae of two ecologically and economically important oysters

7 OYSTERS Sydney rock oyster Saccostrea glomerata Pacific oyster Crassostrea gigas Fisheries 2006 John McCabe 2005

8 OYSTERS Sydney rock oyster Saccostrea glomerata Pacific oyster Crassostrea gigas Flox 2008 Australia & New Zealand

9 OYSTERS Sydney rock oyster Saccostrea glomerata Pacific oyster Crassostrea gigas Flox 2008 Wikimedia 2007 Australia & New Zealand World wide distribution

10 OYSTERS Sydney rock oyster Saccostrea glomerata Pacific oyster Crassostrea gigas Flox 2008 Flox 2008 Australia & New Zealand Introduced 1940 s

11 OYSTERS Sydney rock oyster Saccostrea glomerata Pacific oyster Crassostrea gigas $65 million Tucker 2007

12 TEST STAGES PART 1 Two stages of development: Fertilisation D-veliger 40 µm 25 µm 2 hrs hrs Suspended in water column

13 EXPERIMENTAL DESIGN Fisheries 2006 John McCabe 2005 Gametes collected induced spawning Eggs Sperm Transferred into pco 2 and temperature treatments 18 C 22 C 26 C 30 C 50 eggs/ ml; 7 x 10 5 sperm/ml 375 ppm 375 ppm 600 ppm 600 ppm 750 ppm ppm ppm 1000 ppm 10 ml subsample 2 hrs % fertilisation n = 3 D-veliger Shell length 48 hours

14 Fertilisation (%) FERTILISATION: RESULTS Fertilisation decreased with increased pco 2 (pco 2 and temperature P < ***) Comparison of Sydney Rock and Pacific Oyster Pacific oyster Sydney rock oyster Fertilisation greatest lowest at: at 26 C for both species 18 C at 1000 ppm for SRO 50 % reduction 30 C at 1000 ppm for PO 31 % reduction pco 2 (ppm) and temperature ( C)

15 D-VELIGER RESULTS Reduced Increased development abnormality Figure 1. Ambient 375 ppm Figure 2. Elevated 1000 ppm

16 Shell length (µm) SHELL LENGTH OF D-VELIGERS Shell length decreased with increased pco 2 (pco 2 x temperature P < ** SRO; * PO) Pacific oyster Sydney rock oyster SRO Shell No length development greatest lowest at: at: 30 C at ppm C at for both SRO species: 33 % reduction SRO 22, 26 & 30 C for PO 12 % reduction for PO Lethal effects pco 2 (ppm) and temperature ( C)

17 SUMMARY PART 1 Ocean acidification and temperature had a significant impact on the embryonic and larval stages of the Sydney rock and Pacific oyster

18 PART 2 Do genetic differences in oysters have the potential to ameliorate these impacts???

19 SELECTIVE BREEDING Selective breeding programs used in major aquaculture industries for many years SRO selectively bred for fast growth as well as resistance to disease This study used two selectively bred lines and a control line: Georges River 6 generations fast growth QX resistant Quibray Bay 6 generations fast growth Winter mortality resistant Control No selection

20 TEST STAGE PART 2 Spat 40 µm 100 µm 55 µm 3-4 wks Newly metamorphosed

21 EXPERIMENTAL DESIGN SELECTED LINES Newly Transferred Larvae Fed metamorphosed Shell known of mass length into daily seawater selected measured algal spat diet of and containing selected after of pair Chaetoceros 4 mated days the and pco control lines 2 muelleri, were Pavlova collected (graphed lines treatments lutheri of during were as and growth) collected the Tahitian spat stage Isochrysis 26 C Mean size before experiment 375 ppm ambient 1000 ppm elevated Mean size after experiment n = 3 30 larvae/ container

22 Growth (µm) SELECTED LINES Georges Significant River Decrease decrease reared at in in elevated growth HOWEVER... differed had at increased better significantly growth pco 2 (P than < ***) Control oysters at ambient % % 64 % Control Quibray Bay Georges River Selected line and pco 2 (ppm)

23 PAIR MATED LINES Georges River selected line + Pair mated family lines + Pair mated family lines Line 1 Line 2 Line 3 Line 4 Line 5 Line 6 Line 7 Line 8 Line 9 Line

24 Growth (µm) PAIR MATED LINES 800 Growth Except decreased 1 and 9 with = NO increased significant pco difference 2 (P < ***) L1 L2 L3 L4 L5 L6 L7 L8 L9 L10 Pair mated line and pco 2 (ppm)

25 SUMMARY PART 2 Selectively bred > Control Oysters Oysters may have an adaptive capacity to ocean acidification stress

26 PART 3 Identifying the underlying mechanisms responsible

27 Size 2 Dimensional Gel Electrophoresis powerful protein separating technique which separates proteins based on charge and size Charge pi kda Šeda et al., 2006 used to compare proteins in different samples (Görg et al. 2000)

28 Two dimensional electrophoresis (2DE) detect differences in: 1. control and CO 2 stressed oyster embryos 2. wild type vs. selectively bred

29 Differences in protein expression can be on vs. 2D off. GEL RESULTS Fig 1. ambient 375 ppm Fig 2. elevated 1000 ppm

30 or differences in relative protein concentration Fig 1. ambient 375 ppm Fig 2. elevated 1000 ppm x x

31 SIGNIFICANCE Acute studies have shown that oysters are particularly vulnerable to ocean acidification and temperature Some oysters show an adaptive response of to climate change If we can isolate the genes and/ or proteins involved in this adaptive response, then we may be able to climate proof oyster industries

32 2 1 3 Flox 2008 THANK YOU Acknowledgements: Department of Primary Industries, Port Stephens, New South Wales (1); Dr David Raftos and Emma Thompson, Macquarie University (2); Dr Bronte Tilbrook CSIRO Tasmania (3)