My son is a magnet for mosquitoes and we will see absolutely no mosquitoes on the boat but he will wake up with mosquito bites all over him! We joke that we bring him along so that we don't get bit! Things that have worked for him are the Picaridin lotion (you get it through Amazon) and the Off Wipes. With the lotion you only have to apply it every 8 hours but it is pretty potent stuff. Lots of precautionary statements on the label. The worst place we have experienced for noseeums/sand fleas is Trellis Bay on shore. They are brutal and way more aggressive than mosquitoes.