Cook pasta. Drain in a colander over a bowl, reserving ¼ cup cooking liquid.
Heat oil in medium saucepan over medium-low heat. Add shallots; cook 5 minutes, stirring frequently. Add wine; simmer 8 minutes or until reduced to about ½ cup. Add sour cream, stirring with whisk until smooth. Remove from heat; stir in peas and salmon.
Combine pasta and reserved cooking liquid with cream sauce. Stir in juice and tarragon. Let stand 3 minutes for pasta to absorb sauce. Season with salt and pepper, if desired. Serve warm.
