Alterra Capital Holdings Ltd suffered a $46.7 million net loss during the first quarter of 2011, impacted by the Japanese and New Zealand earthquakes and Australian floods.That compared to a profit of $36.4 million for the same quarter of 2010.Alterra, formerly known as Max Capital Group Ltd, was formed in May 2010 as a result of the merger of Max and Harbor Point Ltd. The company made a net operating loss for the quarter of $24.7 million, or 23 cents per share, compared to a net operating income of $40.7 million, or 71 cents per share, last year.Annualised net operating return on average shareholders’ equity for the first quarter of 2011 was minus 3.5 percent.Marston (Marty) Becker, president and CEO of Alterra, said: “The first quarter of 2011 was marked by the effects of major property catastrophe events in Japan, New Zealand and Australia. These have been significant industry events; however, our strategy of diversifying and limiting our property catastrophe risk exposures resulted in a manageable level of losses and limited the capital impact to less than 4.5 percent of our 2011 opening shareholders’ equity - in line with our previously announced estimates.“Looking ahead, as a result of the first quarter property catastrophe events, we expect to see improved pricing conditions in the international property reinsurance arena. With our strong capital base and first-rate talent, we believe that we are very well positioned to participate in attractive underwriting opportunities that emerge in this market.”Property and casualty gross premiums written rose 69.4 percent to $627.4 million, while net premiums earned were $379.5 million, representing an increase of 96.1 percent.The increases reflected the impact of the merger with Harbor Point - whose premiums were not included in the 2010 results of operations - as well as from new operations in Latin America and new product offerings of Alterra at Lloyd’s.But they were partially offset by decreases in previously existing operations where writings were reduced due to unattractive returns.The company also reported a combined ratio on property and casualty business of 112.5 percent compared to 90.5 percent for the same quarter of 2010 and property catastrophe event and significant per-risk net losses of $115.5 million ($106.3 million net of reinstatement premiums) compared to $9.6 million last year.Incurred losses net of reinsurance and reinstatements for the major events included $83 million from the Japan earthquake and tsunami, $14 million from the New Zealand earthquake and $9.3 million for the Australian floods and storms.Net favourable development on prior years’ loss reserves was $30.2 million or eight combined ratio points versus $17.1 million or 8.8 combined ratio points in the same quarter of 2010.Net investment income was up 19.4 percent at $57.8 million from $48.4 million in the same quarter of 2010.Alterra also recorded a loss of principal of $25 million on a catastrophe bond investment triggered by the Japan earthquake and tsunami, included within net realised and unrealised losses on investments.Under the board-approved share repurchase authorisation, Alterra bought back nearly 6.2 million common shares during the quarter at an average price of $21.91 per share for a total of $135.5 million. As of March 31, 2011, $192.2 million remained under the board-approved share repurchase authorisation.Shareholders’ equity was $2.72 billion as of March 31, 2011, a decrease of 6.7 percent from December 31, 2010. Diluted book value per share as of March 31, 2011 was $25.34, a drop of 2.5 percent from the end of last year.