The following are the details of the calculation of the Exchange Ratio:
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Five day
Weighted
Average
Record Trading Effective
Date of Bonavista Price of Date
Bonavista Energy BNP.UN of the Exchange
Energy Trust (Prior to Increase Increase Ratio
Trust Opening Distri- the end in in as of
Distri- Exchange bution of the Exchange Exchange Effective
bution Ratio per Unit Month) Ratio (xx) Ratio Date
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March April
31, 2005 1.26135 $0.275 $29.16 0.01190 15, 2005 1.27325
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(xx) The increase in the Exchange Ratio is calculated by multiplying the Bonavista Energy Trust Distribution per Unit by the Exchange Ratio immediately prior to the Record Date and dividing by the five day weighted average trading price of BNP.UN.
A holder of Bonavista Petroleum Ltd. Exchangeable Shares can exchange all or a portion of their holdings into Bonavista Energy Trust Units, at any time, by giving notice to their investment advisor or Valiant Trust Company at its principal transfer office in Suite 310, 606 - 4th Street S.W., Calgary, Alberta, T2P 1T1.
Please visit our website at www.bonavistaenergy.com for detailed corporate information.
FOR FURTHER INFORMATION PLEASE CONTACT:
Bonavista Energy Trust Keith A. MacPhail President & CEO (403) 213-4300 or Ronald J. Poelzer Executive Vice President & CFO (403) 213-4300 or Greg R. Warner Vice President, Finance (403) 213-4300 or Bonavista Energy Trust 700, 311 - 6th Avenue SW Calgary, AB T2P 3H2 Website: www.bonavistaenergy.com

