Can a boy at the age of 17 be charged with statutory rape for having sex with a 16 year old girl?

Yes, a minor can be charged with statutory rape and the case can be moved from juvenile to adult court depending on the judges recommendations.

Wisconsin Criminal code; 948.09 Sexual intercourse with a child age 16 or older.

Who ever has sexual intercourse with a child who is not the defendant's spouse and who has attained the age of 16 years is guilty of a Class A misdemeanor. Maximum sentencing if charged as an adult for a misdemeanor could be probation or incarceration for not less than 6 months and not more than 2 years. Fines may also be imposed.