Tabanos are large yellow flies, similar to horse flies, prevalent during the summer months, but found here all year 'round, especially on beaches outside of Cancun. The tabano has a distinctive flight pattern of rapid circles around its potential victim. It's always a good idea to kill any tabano that starts stalking you, as they tend not to give up once they make up their mind to bite. This is easier if two people cooperate. Generally speaking, you will not feel the bite itself, but there will be an extremely intense itch soon afterward. It can be quite painful, lasting for days. Many people are completely immune to tabano bites, but others suffer an allergic reaction in which the bitten area swells, sometimes grotesquely. We haven't discovered any real remedy for tabano bites. I used to get the swelling, but now seem to be more immune. I found some relief by holding the affected area under the hottest water I could stand, which intensified the itch at first, but then reduced the annoyance.