We were on Bonaire & Curacao 1 week each around Memorial Day last year - and both islands had 'unseasonable' rains just before we got there, so the buggers (skeeters) took advantage to breed while they could. Mostly a problem at night, as the windows etc. don't have screens - close up the place and run the A/C before darkness falls if it's similar conditions this year. I don't remember them being a problem at open-air restaraunts, even after dark though - mainly at the accomodations.
They were tiny - not like the ones where I grew up, which if they learned to co-operate, three or four working together might manage to carry off chihuahuas. All the more maddening to find them after they got indoors after dark.
Have a great trip - hope you have the opportunity to dive every site everyone submitted as a favorite, so you can give us your reviews adding to the list!