South African private bank Investec continues to navigate a "steady" course through the "uncertain" global environment, maintaining profitability across the group in the first quarter.Net operating income for the quarter to 30 June 2009, after expenses and minorities but before impairments on loans and advances, fell 12% from the same time last year.Defaults have continued to grow in line with expectations. The credit loss ratio on core loans and advances rose to 0.8% annualised for the quarter from 0.3% in 2008. All this means attributable earnings are down 26%, although Investec says it is trading "well ahead" of the last quarter of the 2009 financial year.In the three months since the 31 March year end, core loans and advances grew 1% to £16.3bn, customer deposits rose 6.4% to £15.5bn and third party assets under management was up 9.7% to £53.6bn. "Investec's recurring revenue base and operational diversity have continued to support profitability across its core geographies," it said Friday."The group has maintained its disciplined focus on managing risk, building capital and preserving liquidity. Operating fundamentals and activity levels within the group's businesses, however, continue to be negatively impacted by weak global economic conditions."