we went in July and were bitten to pieces
funny thing is we've been to Puerto Pollensa loads of times before and never been bitten before....
we never saw the little blighters...as Pollensa1946 says, you're OK in your room...but who wants to stay in there all evening??
incidentally we're both blood group A so that theory "bites" the dust
and the bites were small, but REALLY itchy
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and they found all the little corners where we hadn't applied the lotion we quickly bought...including biting through thin trousers etc....favouring inner arms and the panty line/thighs
good luck......