Parasites of commercial fishes as

bioindicators of marine pollution:A preliminary study

Ana Pérez-del Olmo, Mercedes Fernández, Francisco E. Montero, Juan Antonio Raga & Aneta Kostadinova

Cavanilles Institute of Biodiversity and Evolutionary Biology

University of Valencia, Spain

Vertimar 2005

External anomaliesLength-weight relationshipsDetoxifying enzymesHematological valuesHistopathologyPollutant concentrationParasitism

Bioindicators in marine organisms

Bioindicators in marine organisms

External anomaliesLength-weight relationshipsDetoxifying enzymesHematological valuesHistopathologyPollutant concentrationParasitism

Parasites as Bioindicators Transmission through trophic webs (Marcogliese

& Cone, 1997)

Alteration of parasite´s environment (Khan, 1987)

Life cycles shorter than those of their hosts

Heavy metal accumulation (Sures, 2003)

More parasitic than free living species (MacKenzie, 1999)

“Exxon Valdez” (Alaska)24.03.1989

“Amoco Cadiz” (France)16.03.1978

Boops boops (Bogue – Boga)

Micromesistius poutassou

(Blue whiting – Lirio)

AimTo investigate the medium-term impact of the oil spill from the “Prestige” using

pre- and post-spill information on parasite infections from two commercial

fish.

“Prestige” oil spill

13.11.2002

2980 km affected

Micromesistius poutassouFamily Gadidae

aa

MesopelagicSmall crustaceans (euphausiids, amphipods). Large individuals may prey on fish and cephalopods

3000 m

160 m30 – 400 m

Vigo

60 fish: 2000 & 2004Micromesistius poutassou

Vigo

DigeneaDigenea(benthic-neritic)(benthic-neritic)

NematodaNematoda(pelagic)(pelagic)

Distribution of abundance

Before After Mean SD CV (%) Mean SD CV (%)

Significance

NEMATODA 16.9 8.7 51.5 9.3 6.4 68.7 *** Anisakis simplex ( Rudolphi, 1809) 16.8 8.7 51.7 8.9 6.4 71.3 *** Hysterothylacium aduncum (Rudolphi, 1802) 0.1 0.3 259.3 0.3 0.7 190.0 ns DIGENEA 3.0 3.1 102.1 0.8 1.0 135.5 ** Stephanostomum spp. 2.7 3.1 112.4 0.7 1.0 147.9 * Prosorhynchus crucibulum (Rudolphi, 1819) 0.3 0.6 218.7 0.1 0.3 315.9 ns

Boops boopsFamily Sparidae aaaaaaaaaa

Inshore Waters (1 - 200 m)Demersal or semipelagic above various bottoms Omnivorous (young mostly carnivorous, adults mostly herbivorous)

Malpica

Vigo

OndarroaOndarroa

120 fish: 2001 & 2004Boops boops

2001-2004 2001

2001

Parasites of Boops boops

Total: 26 metazoan parasites

Isop. Copep. Monoge.

Nematod.

Acantho.

Cestod.

Digen. Total

Vigo 1 - 1 2 - - 10 14

Malpica 1 1 - 1 2 - - 10 14

Ondarroa 1 - 2 2 - - 8 13

Malpica 2 2 2 2 2 1 1 16 26

Before Vigo After Malpica 2Malpica 1 Ondarroa

8.831.6 361.57235.8 4.171.8 36.7027.7 5.001.2 56.2329.5 4.231.4 52.0744.7

Before

After

Parasite richnessmean SD

Parasite abundance

mean SDMalpica (M2)Malpica (M1)

Vigo (V1)Ondarroa (O1)

Parasite Communities

0

50

100

150

Samples

P (%)

M2 M1 V1 O1

ns

***

Monoxenous parasites: Prevalence

direct cycle-ectoparasites

Prevalence of monoxenous by group

Monoxenous parasites: Species richness

ns

***

ns

***

Monoxenous parasites: Abundance

MONOXENOUS PARASITES (direct cycle-ectoparasites)

HETEROXENOUS PARASITES(indirect cycle-endoparasites)

Ratio Sm/Sh

Diamant et al. (2003)

ns

***

0,000,050,100,150,200,250,300,350,400,450,50

Samples

Sm/Sh

M2 M1 V1 O1

PAHsImmunosupression

ELEVATED LEVELS OF MONOXENOUS INFECTIONS

Gill hyperplasiaExcessive mucous secretionCoagulation of mucus

Haensy et al. (1982): Amoco Cadiz oil spill Moles & Wade (2001): experimental studyKhan (1990; 2003): experimental & field studies

Pollution & Parasites

increase

Immunosupression

EctoparasitesEctoparasites Endoparasites

decrease

Interruption of life cycles

MacKenzie (1999), Khan (2003)

* No substantial perturbation of the benthic intermediate hosts

0

50

100

150

200

250

300

350

400

Samples

No. I nd.

M2 M1 V1 O1

ns

***

Heteroxenous parasites: Abundance

Heteroxenous parasites: Species richness

ns

***

0

1

2

3

4

5

6

7

Samples

No. sp.

M2 M1 V1 O1

0

50

100

150

200

250

300

350

400

0 2 4 6

Mean no. of sp.

Mea

n no

. of i

nd.

Still …

3 Atlantic3 Mediterranean

Future research

Parasitism Length-weight relationshipExternal anomaliesHematological valuesHistopathologyPollutant concentration

Thanks are due to:Ministerio de Educación y Ciencia (APO

holds a FPU grant and MF holds a “Ramón y Cajal” contract)

Fundación Azti (Sukarrieta), IIM (CSIC)Pescados Rivas (Fisterra), Lonjas de Bueu

y RibeiraUnidad de Zoología Marina (ICBIBE,

Universitat de València)

Thanks for your attention!

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Micromesistius poutassou