Winner 2012

FishHealth, the 2012 R&D Award Winner

A methodology for a physiology-based, ecologically relevant assessment of fish health, to provide information on the impact of chemically dispersed oil on marine fish.

The winner of the 1st ITOPF R&D Award in 2012 was FishHealth, a consortium of four research institutes led by LEMAR (Laboratoire des Sciences de L’Environnement Marin, France), partnered with CEDRE (Centre de Documentation, de Recherche et d'Expérimentations sur les Pollutions Accidentelles des Eaux), CNR-IAMC Oristano (Consiglio Nazionale delle Recherche, Italy) and the Zoology Department at UBC (University of British Columbia, Canada).

The project is receiving funding from ITOPF for 3 years, which commenced in June 2012. 


Project aims

The FishHealth project aims to:

1. Validate a methodology to assess the health status of a fish population, diagnosing fish condition with tolerance tests in a manner analogous to studies in human health.

2. Determine the threshold for fish avoidance reactions to water soluble fractions (WSF) of oil and to suspended oil droplets due to dispersant treatment, examining fish behavioural response (avoidance reaction and spatial distribution) to increasing doses of oil droplets and water soluble fractions.

3. Investigate the dose-effect relationship on fish in the presence of oil and dispersant and, by transferring the treated fish to semi-natural field conditions, evaluate the capacity of the proposed methodologies to provide a future prognosis for an affected population. This can potentially provide operational information for the use of dispersants in coastal waters.


Why ITOPF funded the project

From ITOPF’s perspective, the project addresses two areas of “fish health” where the results may have a direct input into the operational aspects of the response to an oil spill:

  • Seafood quality – assist in assessing the potential risks of tainting of fish stocks when dispersants are used.

  • The impacts of dispersant use on fin fish populations – provide information on whether fish survival/growth of stocks exposed to dispersants might be impacted in the medium- and longer-term.

Both these areas have obvious economic considerations when managing fish stocks during a spill (e.g. harvesting bans) and on the potential claims for compensation for longer term reduced fish ‘health’ (e.g. reduced reproductive capacity, increased mortality etc.). Linked closely with these points are the operational considerations whereby questions regarding whether or not to use dispersants (due to concerns for the local fish stocks) can be evaluated alongside scientific data to support the advice given.


Results

By the end of the first year, the project had achieved two of its original objectives. The protocols used for assessing the impact of untreated oil and dispersant treated oil have been validated as relevant indictors of fish health. Transfers to field conditions also demonstrated that performances during our standardized tolerance tests are predictive of fish performance in natura.

In terms of findings, to date results indicate that 45 days following  oil exposure ecologically-relevant performances such as growth, maximum swimming speed or tolerance to reduced oxygen availability and increased temperature were not affected. However, treating oil with dispersant was associated with reduced growth, swimming capacity and hypoxia tolerance.

1. Health status

Assessment of the effects of oil and dispersant exposure on three performance traits involved in environmental adaptation (hypoxia tolerance, temperature susceptibility, swimming performance) as they are key determinants of individual’s ability to meet the needs for everyday life.

The tests included a phase in the laboratory to validate the methodology followed by a field validation of the ecological relevance of the possible impaired performances resulting from oil exposure.

Hypoxia challenge test
Hypoxia measurement

2. Avoidance reaction

Avoidance reactions from fish to hydrocarbons have been poorly studied and existing results are conflicting. To date there is no understanding of the underlying mechanisms.

Choice box with two simultaneous flows
(dispersed oil and clean water), allowing
the fish to freely move from one flow
to another

Further research

Further testing will be carried out to determine whether the dysfunctions observed are maintained over time and can be ascribed with any ecological relevance. Field experiments are also currently underway.