THE construction of a £1.3-billion wind farm off the Sussex coast has been temporarily halted due to spawning fish.

Work on the foundations for 116 wind turbines for the Rampion Offshore Wind Farm will not resume until July because of shoals of brooding black seabream.

Usually found around the inshore shelf at depths up to 300m, the oval-shaped fish breed between February and May, leaving eggs near the sea bed. Feeding on seaweed and tiny creatures, they can change sex from female to male.

To avoid impacting on the black seabream, experts are also looking at the best way of dealing with unexploded wartime bombs discovered nearby in March. An exclusion zone was set up three miles off Shoreham where two 500-pounders were found.

A spokesman for E.ON, which is delivering the 116-turbine initiative alongside the UK Green Investment Bank, said: “Planned construction of the Rampion Offshore Wind Farm remains on track and is unaffected by the recent unexploded ordnance discovery, for which experts are determining the best course of action.

“We have now installed 18 turbine foundations and, as planned, piling work has now been paused to protect the black bream spawning season.”

A spokesman for the Marine Management Organisation (MMO) said the spawning fish were identified after a marine licence application was lodged over the unexploded ordnance and to relocate sea bed boulders.

The MMO placed a condition on the licence, stating ordnance cannot be exploded between April 15 and June 30. The condition can be varied, however, if Rampion can prove through noise modelling that detonating the unexploded devices will not disturb the spawning seabream.

The boulder relocation can still go ahead during the restricted period.

The MPI Discovery vessel, the large ship used to lay the foundations, has left the site until major work resumes.

Regarding the bombs, a Rampion spokesman said: "Local people should not be concerned and offshore construction is unaffected by this find."

The Maritime and Coastguard Agency said E.ON, as a commercial company, would deal with the ordnance itself.

The Rampion wind farm has been under construction since last September and is set to be completed next year.