U n ivers id add e O vied o

THE EFFECT OF THE PRESTIGE OIL SPILL ON THE PHYTOPLANKTON IN THE N-NW SPANISH

COAST DURING SPRING Manuel Varela*1, Antonio Bode1. M Teresa Alvarez-Ossorio1 Ricardo Anadon2,

Marcos LLope 2 Luis Valdes 3 Carlos Garcia-Soto 4

1 Instituto Espanol de Oceangrafia. Muelle de Animas s/n. A Coruña. Spain

2 Laboratorio de Ecologia. Universidad de Oviedo. Spain

3 Instituto Espanol de Oceanografia. Paseo del Arbeyal s/n. Gijón. Spain

4 Instituto Espanol de Oceanografia, Promontorio de Sa Martín s/n. Santander. Spain

Why Spring ?

• It is the first important biological event after shipwreck

• Bloom of phytoplankton in the area

• Spawning of many species of fishes and shellfish of commercial interest

• Effects on plankton ---- effects on food web

Source of Data

• Instituto Español de Oceanografia Core Project: Studies on Times Series of Oceanographic Data

– Starting in 1988 in A Coruna

– Several localities of study in the N-NW Coast of Spain

• Pelacus Cruises– Cover the area from Portugal to France

• OmexII Satellite Data – For the area in front of Rias Bajas

• Satellite chlorophyll IEO– Gijon Radial

7°W

5°W

43°N

42°N

5°W

0°W10°W

7°W

45°N

50°N

40°N

A Coruña

Vigo

Gijón

Santander

Cudillero

200 m

Cape Finisterre

Bay of Biscay

Galicia

NG

SG

WBB EBB

Area of study

Have effects on phytoplankton been observed after the Prestige oil spill during spring?

• Effects on biomass (chlorophyll-a)• Effects on physiology (primary production)• Effects of taxonomic groups• Effects on main phytoplankton species

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1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 20030

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100

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300A Coruna shelf station chlorophyll

Effects on biomass (chlorophyll-a)

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1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 20030

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300Cudillero shelf station chlorophyll

Effects on biomass (chlorophyll-a)

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1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 20030

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1200A Coruna shelf station primary production

Effects on primary production

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1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 20030

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1400Cudillero shelf station primary production

Effects on primary production

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199019911992199319941995199619971998199920002001200220030

25000

50000

75000

100000A Coruna shelf station diatoms

Effects on diatoms

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1995 1996 1997 1998 1999 2000 2001 2002 20030

25000

50000

75000

100000Cudillero shelf station diatoms

Effects on diatoms

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199019911992199319941995199619971998199920002001200220030

2000

4000

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8000A Coruna shelf station dinoflagellates

Effects on dinoflagellates

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1995 1996 1997 1998 1999 2000 2001 2002 20030

2000

4000

6000

8000Cudillero shelf station dinoflagellates

Effects on dinoflagellates

Main phytoplankton speciesA CORUÑA

Groups and species %n mean sd %n mean sdDinoflagellates

Heterocapsa niei 39 2.0 3.9 75 0.9 0.6Gyrodinium glaucum 22 0.1 0.2 75 0.4 0.3Prorocentrum balticum 33 1.3 5.2 50 4.9 8.4Scrippsiella trochoidea 24 0.5 2.1 25 0.1 0.1Torodinium roubustum 33 0.2 0.3 50 0.3 0.3

DiatomsAsterionellopsis glacialis 33 1.7 4.5 25 0.2 0.3Chaetoceros affinis 24 2.3 8.2 75 1.4 1.4Chaetoceros compressus 16 12.9 70.5 25 0.9 1.5Chaetoceros curvisetus 14 15.7 104.0 20 0.1 0.2Chaetoceros didymus 29 5.1 15.8 50 0.9 1.4Chaetoceros socialis 65 377.5 1138.1 75 31.6 44.0Chaetoceros spp 47 4.3 14.2 75 16.5 21.0Detonula pumila 43 13.3 26.3 20 0.1 0.1Guinardia delicatula 51 13.7 52.3 100 2.9 2.0Guinardia striata 14 0.3 1.6 25 0.5 0.9Lauderia borealis 20 5.6 18.8 25 0.1 0.2Leptocylindrus danicus * 51 19.7 59.9 75 151.6 258.5Leptocylindrus minimus 12 0.6 1.8 25 1.6 2.7Nitzschia sp 14 1.5 4.9 50 0.7 0.9Nitzschia longissima 51 1.3 2.5 75 2.0 2.2Pseudo-nitzschia pungens 57 12.7 28.1 75 6.3 9.5Pseudonitzschia delicatissima 10 0.6 2.5 50 0.8 1.2Skeletonema costatum 39 13.8 46.2 25 0.1 0.1Thalassionema nitzschoides 35 1.2 3.7 75 1.7 1.2Thalassiosira fallax 22 0.9 2.8 50 1.1 1.6

Other phytoplanktersPhaeocistis pouchetii 33 3.0 7.3 25 1.8 3.1Solenicola setigera 22 9.4 46.9 75 10.6 17.6

CUDILLERO Before (1995-2002) After (2003)Groups and species %n mean sd %n mean sd

DinoflagellatesHeterocapsa niei 29 0.4 0.9 25 0.1 0.1Prorocentrum balticum * 14 0.1 0.4 100 3.2 2.6Scrippsiella trochoidea 57 0.6 0.8 50 0.2 0.2

DiatomsAsterionellopsis glacialis 14 0.2 0.7 50 0.2 0.2Bacteriastrum hyalinum 14 1.3 3.3 25 0.1 0.1Cerataulina pelagica 21 0.3 1.1 25 0.1 0.2Chaetoceros curvisetus * 14 0.2 0.6 50 16.5 16.5Chaetoceros danicus 29 0.4 0.9 25 0.1 0.1Chaetoceros socialis 7 121.4 437.7 50 191.0 191.0Detonula pumila 57 11.6 26.7 50 0.1 0.1Guinardia delicatula 57 38.3 109.2 25 0.1 0.1Leptocylindrus danicus 71 67.0 224.8 100 46.1 43.6Leptocylindrus minimus 7 0.1 0.3 50 24.6 24.6Pseudo-nitzschia pungens * 93 3.1 5.3 100 93.2 93.1Rhizosolenia setigera 36 0.4 1.1 25 0.1 0.1

Before ( 1990-2002) After (2003)

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SG Bf SG Af NG Bf NG Af WB Bf WB Af EB Bf EB Af0

20

40

60

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120

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180Integrated Chl a Pelacus Cruises

Effects on biomass during Pelacus Cruises

Bf: 1999-2002Af: 2003

1998-2002 20030

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Satellite Primary Production

Ocean

Ocean

Shelf

Effects on primary production OMEX II Box Area

Radial Gijon. Instituto Español de Oceanografia

Final Remarks

•No effects on phytoplankton at several levels

•Differences are the result of natural variabiliy of ecosystem

Why effects have not been observed?

Low solubility of Prestige fuel

Low concetrations in waterLow concentations in planktonLow aromatic contentHigh density--sinkingPristane/Phytane ratio no Prestige

Plankton mechanisms remove oil from surface waters

•Zooplankton: grazing on oil particles–Fecal pellets sinking to bottom

•Diatoms: adsorption on silica wall –eventual sinking to bottom

•Detritus and clay particles: adsorption–Aggregates and eventual sinking

A Coruna Zooplankton: oil in the gut content

CONCLUSIONS

• No effects have been observed on phytoplankton during spring blooms for biomass, production and community structure

• We can not ascertain whether or not oil has affected phytoplankton– Large variability caused by meso and large-scale

processes masks any effect

– Effects reduced or short-lived. No effect on spring bloom

Acknowledgements

• Technical assistance– Teodoro Patrocinio Ibarrola– Jorge Lorenzo Salamanca– Leticia Viesca Lombardia

• Crew of R/V– IEO (Lura, Rioja, Navaz)– IFREMER (Thalassa)

• Projects– CICYT Aes: Reconocimiento Oceanografico en la época de floración

primaveral en Galicia y Cantábrico– IEO: Studies on Time Series of Oceanographic Data– EU: Pelasses and Sardyn