Duncan Nightingale to Augment International Exploration and Production
    Management Team

CALGARY, Sept. 24 /PRNewswire-FirstCall/ - Gran Tierra Energy Inc. (NYSE Amex: GTE; TSX: GTE), a company focused on oil exploration and production in South America, today announced it has appointed Duncan Nightingale to Vice President of Exploration. Based in Calgary, Mr. Nightingale will lead the company's exploration operations, including the 14 well exploration drilling program commencing in the fourth quarter of 2009, and continuing through 2010.

"With extensive experience in international exploration and production, and a proven track record of reserve additions, Mr. Nightingale is a welcome addition to our corporate team in Calgary," said Dana Coffield, President and Chief Executive Officer. "In addition to playing a critical role in supporting our 2009 and 2010 drilling program, Mr. Nightingale will also work towards expanding our portfolio of exploration prospects in Colombia, Peru, Brazil, and Argentina."

Duncan Nightingale has more than 28 years of corporate head office and resident in-country operating experience in regions that include the Middle East, Far East, Latin America, North Sea, Eastern Europe, Australasia, North, East and West Africa, and the Commonwealth of Independent States (former Soviet Republics). He has extensive experience with all aspects of exploration program management, development and production operations, new business ventures, portfolio management, and strategic planning. He has successfully led multi-disciplinary teams and built a proven track record of reserves additions at companies including Artumas Group Inc., Dana Gas PJSC, EnCana International, and Nexen International Exploration. Duncan holds a Bachelor of Science (with honors) in Geology and Geophysics from the University of Nottingham.

About Gran Tierra Energy Inc.

Gran Tierra Energy Inc. is an international oil and gas exploration and production company, headquartered in Calgary, Canada, incorporated in the United States, trading on the NYSE Amex Exchange (GTE) and the Toronto Stock Exchange (GTE), and operating in South America. Gran Tierra Energy holds interests in producing and prospective properties in Argentina, Colombia and Peru, and has opened a business development office in Rio de Janeiro, Brazil. Gran Tierra Energy has a strategy that focuses on establishing a portfolio of producing properties, plus production enhancement and exploration opportunities to provide a base for future growth. Additional information concerning Gran Tierra Energy is available at www.grantierra.com.

Gran Tierra Energy's Securities and Exchange Commission filings are available on a web site maintained by the Securities and Exchange Commission at http://www.sec.gov and on SEDAR at http://www.sedar.com.

SOURCE Gran Tierra Energy Inc.