OTO, Iowa (AP) – Authorities say an Ida County man has drowned in an accident on the Little Sioux River near Oto in western Iowa.  Woodbury County Sheriff’s Maj. Greg Stallman says 23-year-old Derick Vielguth was with three friends when he slipped on a rock and fell into the swift-flowing river about 10:30 a.m. Sunday.  One of the friends jumped in to help but was unable to get him out of the river.  The man’s body was recovered a little before 2 p.m., about 30 yards from where he’d fallen in.