First-half performance figures are showing the same pattern for hedge funds as for more mainstream investors -- the most successful were in fixed income, the least successful in stocks.

The HFRI Fund Weighted Composite Index, a broad measure of hedge fund performance, shows a six-month loss of 0.18 percent at the end of June, following a 0.81 percent fall in June itself.

Within various strategies, however, there was a wide range of performances. Hedge funds focused on corporate debt, for example, gained 4.76 percent for the half year, while the biggest loser was in energy and basic materials, down 4.81 percent.

Fixed-income asset-backed strategies were the best performers, up 6.36 percent.

"Volatility increased significantly in 2Q with concerns about sovereign credit risk, currency policy adjustment, economic and energy market impact of the (BP) environmental disaster and concerns about slowing growth in both developed and emerging economies," HFR, a research firm, said.

"(This contributed) to declines in global equity markets, a powerful late-quarter rally in U.S. Treasury bonds and volatile directional moves in currency and commodity markets."

Another research firm, HedgeFund.net, had a similar finding. Its HFN aggregate index rose just 0.4 percent for the first half after a 0.51 percent loss in June.

It found the best H1 performances in fixed income, up 5.37 percent in aggregate, and stocks in general falling 0.42 percent.

Mortgage plays were the HFN best performers, up 9.85 percent.