Because they are physically so different, it took scientists a long time to recognise that these were all ecologically linked. While one habitat might be used by an adult fish, its larvae usually depend on a different type for their livelihood. The arrangement stops young and old having to compete for the same food, and it's just one example of the complex interactions going on. The reserve is easily reached from either San Pedro or Caye Caulker, with operators running twice daily snorkel and dive trips. Excursions in glass-bottom boats are also run from San Pedro.
Operators also run dive tours from Belize City.
Hol Chan can be comfortably visited in half a day. In the reserve itself, boats moor at designated buoys and reserve staff patrol the area. A short reserve booklet is available from the office. At Hol Chan itself, there is a big red marker, and you are strongly advised not to swim beyond this because the tides through the cut are very strong. The other word of caution is for divers to resist the temptation of exploring any caves.