The only place I have ever had a problem with mosquitoes on Disney property is at Port Orleans Riverside at the quiet pools after dusk. I think the fake bayou look caused some standing water which is a breeding ground for these critters. After about 5 minutes of sitting pool side we had a good dozen mosquitoes buzzing around us so we packed it in for the night, which stinks seeing as a late evening pool adventure is our perfect end to a park day. Other than this one experience I can't recall even seeing a mosquito on property.