Bermuda-based re/insurer Endurance Specialty Holdings last night reported a net loss of $20 million for the third quarter.The company’s resulted by impacted by nearly $100 million of catastrophe losses, as Endurance had announced earlier this month.The net loss broke down to 71 cents per share and compared to net income of $139.1 million, or $2.51 per share in the third quarter of 2010.For the first nine months of the year, the net loss was $66.4 million, or $2.07 per share versus net income of $253.5 million, or $4.33 per share, for the same period last year.Chief executive officer David Cash said: “The third quarter was a tough one for the industry, as we saw continued frequency of severe catastrophe events and adverse weather conditions, combined with historically low interest rates, global economic uncertainty and a competitive marketplace.“Endurance has been able to withstand these challenges, and continues to maintain a very strong balance sheet with prudent reserves and a high quality, short duration investment portfolio.“We have selectively expanded our business within profitable niches while reducing those business lines where returns were below our targets.”Endurance reported net premiums written of $551.3 million, an increase of 22 percent over the same period in 2010.The combined ratio of 104.6 percent included 17.5 percentage points of catastrophe losses, partially offset by the benefit of 7.9 points of favourable prior year loss reserve development.The company reported an operating loss of $24.7 million, or 83 cents share, while net investment income was $14.1 million, a decrease of $39.6 million over the prior year period.Endurance’s book value was $51.63 per share at the end of the third quarter, down 1.1 percent from June 30, 2011.The operating loss on average common equity for the first nine months of the year was 4.6 percent.