The Japanese earthquake and tsunami, flooding in Thailand, the loss of the cruise liner Costa Concordia and the Rena oil spill off New Zealand have created numerous cargo, hull and liability claims, yet underwriting capacity for marine risks remain high and insurers have not looked for significant premium increases, according to a new Marsh report.

It says marine insurance conditions are “generally favourable to buyers”.

This is despite the loss of the Costa Concordia at the start of the year, which will result in the largest ever claim from a single ship – about $US1 billion ($946.6 million) split between hull and liability underwriters.

Marsh’s Marine Practice Chairman Marcus Baker says competition remains strong and there is no expectation the availability of marine insurance will decline in the near future.

“Insurance buyers that can demonstrate they have strong risk-management practices in place may continue to secure rate reductions at the time they renew their insurance policies, though not to the same degree they have in recent years,” he said.

The report notes underwriters have had to look for new areas in which to use excess capacity, due to greater competition.

“Many cargo insurers are now seeking to underwrite stock throughput policies, which provide coverage for stock while it is in distribution or at manufacturing locations, such as warehouses and factories; traditional cargo insurance policies only provide coverage for goods and merchandise while in transit,” the report says.

“A growing number of hull underwriters have also sought to diversify their underwriting portfolios by entering the builders’ risk market.”

Piracy and the seizure of cargo-laden ships in the Indian Ocean and elsewhere continue to be an issue for the cargo insurance market, says the report.

Pirates are becoming more organised and aware of the value of ships and their cargo, with the cargo often exceeding the value of the vessel.