We will be in Rovinj for 3 nights and then traveling to Losinj, without a car. How best to do so? Thank you.
Rome2Rio.com will point you toward options, none of which look particularly good. This appears to be a difficult transfer without a car.
The transit departs from Rijeka (catamaran or bus--the bus takes a ferry). I would consider going to Lovran or Opatija by bus and picking up the next bus there. Depending on schedules, this may warrant an overnight. Autotrans is bus operator; Krilo the catamaran operator.
I'd find someone with a boat.
We found a sea plane!