Island Hopping Charts

ISLAND HPPING

Every month or so you will find a new chart to view or download from this page.

How The Charts Are Created

The soundings for my guides have been taken by several different procedures over the years. In the Exuma Park Guide I used the depth sounder on my boat and a portable unit in my dinghy for depths until the portable unit bit the dust. Then I turned to the old reliable lead line. In fact, about 50% of the soundings in Exuma Park were taken using a lead line. The charts at this point were basically sketch charts. The outlines of the islands were taken from Nassau Land And Surveys Department topographical maps and scanned into my computer where I added everything else using several graphics programs, primarily Paintbrush for Windows. The depths were placed on the charts using a system of crossed bearings, estimates by eye, and simply dead reckoning. This same method was used for the first edition of The Exuma Guide. At this point I began taking soundings for On And Off The Beaten Path using the same method. I had about 75% of the soundings completed for that book when I learned of a better way to create some very accurate charts.

I now use a computer-based hydrographic system in my 12' Quintrex aluminum boat, Data Acquisition Vessel, DAV for short. The system consists of an off-the-shelf GPS and sonar combination that gives a GPS waypoint and depth every two seconds including the time of each observation. The software used records and stores this information in an onboard computer.

When I begin to chart an area, I first put DAV's bow on a well-marked, prominent point of land and take GPS lat/lons for a period of at least twenty minutes. I use the average of all these positions to check against the lat/lon shown on the topos, which are very accurate by the way. I also use cross bearings to help set up control points for my own reference. At this point I then begin to take soundings.

My next objective is to chart the inshore reefs. Then I'll plot all visible hazards to navigation. These positions are recorded by hand on my field notes as well as being recorded electronically. I rely primarily on my on-site notes for the actual construction of the charts. The soundings taken by the system are later entered by hand but it is the field notes that help me create the basis for the chart graphics. The computer will not tell me where a certain reef ends or begins as accurately as I can record it and show it on my field notes. Next I will run the one-fathom line as well as the ten-fathom line (if applicable) and chart these. Here is where the system does most of the work though I still stop to take field notes. Finally, I will crisscross the entire area in a grid pattern and hopefully catch hazards that are at first glance unseen. It is not unusual to spend days sounding an area of only a couple of square miles. This takes a lot of fuel as well as a lot of time when transferring the data to the chart!

Each identical lat/long may have as many as ten or twenty separate soundings. With the help of NOAA tide tables, the computer gives me accurate depths to one decimal place for each separate lat/long pair acquired on the data run. A macro purges all but the lowest depths for each lat/long position (to two decimal places). At this point the actual plotting of depths is begun including the one fathom and ten fathom lines where applicable.

These charts are as accurate as I can make them and I believe them to be superior to any others. They are indeed more detailed than all others showing many areas that are not covered, or are incorrectly represented by other publications. However, it is not possible to plot every individual rock or coral head so the ability to pilot your vessel by eye is absolutely essential. On many of the routes in my guides you must be able to pick out the blue, deeper water as it snakes between sandbanks, rocky bars, and coral heads. Learn to trust your eyes. Remember that on the banks, sandbars and channels can shift over time so that once what was a channel may now be a sandbar. Never approach a cut or sandbar with the sun in your eyes, it should be above and behind you. Sunglasses with a polarized lens can be a big help in combating the glare of the sun on the water. With good visibility the sandbars and heads stand out and are clearly defined. As you gain experience you may even learn to read the subtle differences in the water surface as it flows over underwater obstructions.

The charts will show both deep draft vessel routes as well as some shallow draft vessel routes. Deep draft vessel routes will accommodate a draft of 6' minimum and often more with the assistance of the tide. Shallow draft vessel routes are for dinghies and small outboard powered boats with drafts of less than 3'. Shallow draft monohulls and multihulls very often use these same routes.

All courses shown are magnetic. All GPS latitude and longitude positions for entrances to cuts and for detouring around shoal areas are only to be used in a general sense. They are meant to get you into the general area, you must pilot your way through the cut or around the shoal yourself. You will have to keep a good lookout, GPS will not do that for you. The best aids to navigation when near these shoals and cuts are sharp eyesight and good light.

Not being a perfect world, I expect errors to occur. I would appreciate any input on corrections that you notice as you travel these waters. Email me with your suggestions and/or corrections. If you see me anchored nearby, don't hesitate to stop by, say hello, and offer your input. Your suggestion may help improve the next edition of my guides.

The Current Chart

Green Cay, Bahamas

The prudent navigator will not rely solely on any single aid to navigation,

particularly on floating aids.

No part of this chart may be reproduced, stored in a retrieval system,

or transmitted in any form,

or by any means, electronic, mechanical, photocopying, recording,

or by and storage and retrieval system without the written permission of

Stephen J. Pavlidis.

Datum Used is WGS84

Green Cay

Green Cay, lies on the western side of the Tongue of the Ocean at the western edge of the Great Bahama Bank, and really can’t be considered as part of the Exumas, it is actually much closer to Andros. But Green Cay and its surrounding waters are a favorite fishing grounds for Exuma as well as Androsian fishermen, which is why I have included the island in both The Exuma Guide and the Northern Bahamas Guide.

As shown on Chart EX-56, a waypoint at 24º 02.60’ N, 77º 11.70’ W, will place you approximately ¼ mile west of the western tip of Green Cay if you are approaching from the west, from Andros or the Tongue of the Ocean. If you are approaching from the Exumas, preferably from Warderick Wells or points north of that cay, a waypoint at 24º 03.40’ N, 77º 10.50’ W, places you approximately ½ mile north of Green Cay. In prevailing winds the best anchorages lie along the northern shore of Green Cay, though any spot that you choose that is nearer the Tongue of the Ocean will be certainly open to the surge that originates from that body of water. A couple of anchorages on the southern side of Green Cay offer a lee in northerly winds, but here again the closer you get to the Tongue of the Ocean, the more surge you will have to endure.

Green Cay has a bit of a history in the annals of piracy in the Bahamas. Some of the pirates of three centuries ago were known for their barbarous acts of cruelty, which were not reserved solely for their enemies. Pirates often served their own brand of justice by marooning their fellow pirates, as well as captives, on deserted islands. In 1718, Green Cay played host to a marooning that may have given the island its name. Most maroonings led to death for those marooned, but the lucky band that was banished to Green Cay survived, probably due to the indecisiveness of the very men that marooned them.

Refusing to join his mutinous crew to go a-pyrating, Captain William Greenaway and seven others were set ashore on Green Cay to await their deaths. Just as the new pirates sailed away from Green Cay, they suddenly had a slight change of heart. They returned to Green Cay and collected Greenaway and his men, and brought them out to a captured sloop. They left them aboard the sloop, but before leaving they fouled the main sheet, cut the huge foresail to the size of a small jib, and then continued to slash the sails and rigging to pieces until the sloop was virtually useless. Greenaway and company were now worse off than before. They were without food and water, anchored a mile offshore, and only Greenaway could swim. Greenaway found a small broken hatchet on board and went ashore with the blade tied around his neck. He built rafts from trees and he and his men ferried fruits, berries, and cabbages out to the sloop from the small cay as they went about rebuilding their vessel.

A week later the small band had the sloop fit enough to set sail, but to their horror they saw the pirates returning. They jumped onto their rafts and fled to the safety of Green Cay where they watched the pirates sink their vessel in deep water. For eight days the group lived in the bush, eating berries and fish and hiding whenever the pirates came ashore and called out to them. Promising them safe passage off the cay Greenaway and his men came out of the bush to find that they had been tricked. The mutineers forced Greenaway and two of his men to join their crew and marooned the other five men back on Green Cay.

The five survived for weeks on what little they could eke out of the bush and nearby waters. One day they looked to seaward and saw the pirates returning once more. This time, possibly thanks to Greenaway, the pirates left behind a cask of flour, a bushel of salt, two muskets, two bottles of gunpowder, a container of musket shot, an axe, a dozen knives, and several pots and pans along with three good hunting dogs. With the aid of the dogs the group was able to catch some of the hogs on the cay and dine on roast pork. Before long the small band built a hut and began to wait comfortably for a passing ship. When the happy group finally spotted a sail it turned out to be the pirates again. This time the pirates burned down their hut and ate all their roast pork. They left behind a bottle of rum with a promise never to return.

The mutineers never did return to Green Cay. Soon after leaving Green Cay they were captured by a Spanish ship who, after hearing Greenaway’s story, sent Bahamian John Sims to rescue those marooned on Green Cay.