Atlantic cod and haddock (completed)
Assessment of the effects of oil exposure on the population dynamics and abundances of Atlantic cod and haddock using state-space models
About the project
In this project, we will investigate potential ecological impacts of oil pollution on two economically important fish species in the Norwegian Barents Sea: Atlantic cod (Gadhus morhua) and haddock (Melanogrammus aeglefinus). We aim at identifying potential ecological effects of oil exposure by studying the consequences of life-stage specific mortality on the dynamics and abundaces of these long-lived species using newly developed dynamic state-space models.
The Lofoten-Barents Sea is an area with regular oil traffic and is of increasing interest for oil production. Adverse biological effects from offshore oil industry discharges have recently been suggested for Atlantic cod and haddock. Even though eggs and larvae are particularly vulnerable to oil spills, as they cannot actively avoid oil exposure, population-level effects of reduced survival among early life-stages have rarely been studied so far. We will use the dynamic state-space approach to model the population dynamics by incorporating data from diverse sources, including scientific surveys, commercial catches, and experiments. We will build on an existing framework developed for cod, which will be extended by including early life-stages, species interactions and environmental effects. The models will then be used to simulate effects of age-specific mortality on population dynamics and abundances under various assuptions about abundances of other species, environmental conditions, and fishing pressure. This provides the oppurtunity to evaluate the sensitivity of the stocks to changes in mortality caused by oil spills. By using the state-space approach we can quantify uncertainties associated with the data and evaluate the robustness of the model predictions. The expected results are important for the successful managements of these stocks, particularly in the Lofoten-Vesterålen area where oil production and increased oil traffic are projected close to the species spawning grounds.
This project is funded by the Norwegian Academy of Science and Letters, VISTA.
01.08.2012 - 31.07.2014