There is a guide book called 100 Magic Miles
devoted to yachting in the Whitsundays. I haven't read it but it's reputation is good.
Despite visiting the area over 20 odd years my actual time on the water
is quite small, so I offer the following suggestions. Other members will know more than me for sure.
1) Assuming you're chartering your charter
company will have lots of good suggestions. They may be biased towards keeping their boat safe, but they will also save you lots of hassles.
2) My knowledge is getting a few years old now but the catering companies used to do an excellent job. If there's a few of you even better. A resupply after about three days may be needed. They are good for beer
and soft drinks and basic spirits but if you want really nice wine or top of the range spirits it may be best to bring them with you (pack well in case the 'handlers aim is poor). Don't be afraid to discuss what you want with the caterers.
3) Dropping in to Airlie Beach after a few days should be interesting, and all those things that you forgot can probably be brought there. Saturday used to be market day (please check). The fresh water lagoon
is well worth a swim.
4) The charter
company will probably dictate your mooring/anchorages but including Nara Inlet and Whitehaven Beach in your travels could be rewarding.
5) There can be strong tidal flows between the islands, and when these are opposed by a stiff breeze the result can be quite testing. Best to go with the flow if possible. Your charter company should brief you on this.
6) Bring good quality fins, mask and snorkel with you if you can. They may be available locally but could be time consuming to find, expensive, of poor quality or not fit.
7) Fisherpersons may disagree but I never caught a thing (not even a cold) in 20 years of trying. I did see squid being caught with lights off the end of South Mole jetty once.
8) Check out when the islands have their fancy food
. Some of them used to have quite a feast. I'm sure Hayman will be good if you can anchor
there and can afford it. Hamilton has a range of eateries.
9) Don't forget a few good hats, a couple of SF 50 shirts and lots of sun block. Put the sun block on before you get off the plane. A decent dose of sunburn is going to seriously degrade your holiday experience.
10) Stingers may still be of concern in March and round the islands. Do your research
, check with your charter company and keep the recommended first aid on hand. If you have a thin wet suit or a long sleeved rashie shirt it may be a good idea to bring them.
11) March should be OK but I seem to remember the end of August/September being quite cool. If you have space a light sailing type jacket and windcheater may be appropriate.