The 28 year old centre will not be arriving in Galway until October due to completing the current season in New Zealand with Counties Manukau but Connacht Manager Tim Allnutt sees Ta'auso as a major addition to his side.
"Niva is a very powerful strong running centre," he said. "He's a linebreaker and a good distributor of the ball and we feel he'll improve our play in a crucial area".
Ta'auso will be bringing a wealth of experience with him to Connacht having previously played with the Waikato Chiefs before joining the Highlanders in 2007. He has also been capped 22 times in Super 14 competition and was also capped by the Junior All Blacks in 2006.
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