Which type of GPS should I purchase?

Dear Capt. Paul:

I usually fish the marshes around Lafitte, Bayou Segnette and in and around Vermillion Bay and Rockefeller, and would like to know if the Garmin 76s would be a decent marine GPS for my boating needs, or should I save the cash and buy a nice unit like the Garmin 178c?

Thanks for your help,

Michael Burrows

Capt. Paul’s Response:

You would NOT be wrong to get either of the units; they are both top-of-the-line units in their respective classes.

No doubt about it, the 178c is a very, very good combo GPS/depthfinder/chart plotter, but the Garmin GPSMAP76s is also a very, very good handheld unit. Either of them will accommodate a variety of Garmin MapSource mapping software.

Naturally these mapping programs are considered an accessory and are sold separately. For the inland waters, I suggest that you get the U.S. topo version as your basic mapping. It will show considerably more map detail in the Louisiana coastal marshes than will their blue chart maps in either of the units.

I use the GPSMAP 76 on my bay boat, and am well pleased with the unit.

In addition, the 76 is considered a handheld unit. I use the unit in my truck as well as carry it while hunting and hiking. The Map 76 can hold up to 28MB of Garmin’s MapSource mapping memory. That is just about the entire state of Louisiana.

I mount the MAP 76 in a marine mount, and have installed a 12-volt remote power cable to power the unit when I am on the water. The MAP 76 has one of the largest screens in the handheld line. It does NOT have color-version screens.

The GPS MAP 178 takes Garmin data cartridges that you are require to purchase. These map cartridges come in a variety of memory sizes. To load the topo version of MapSource, you have to have a Garmin card writer and the data chip.

Isn’t it nice to have such a dilemma? Just think, a few years ago technology of this type was considered a fantasy.

Keep in touch, and let me know what you finally decided.

Dear Capt. Paul:

I am contemplating purchasing the Garmin Street Pilot III, Deluxe to use for travel and fishing. I am told it is DGPS-enabled. I can’t find any info to verify this. Help, please.Charlie Daigle

Capt. Paul’s Response:

The GARMIN Street Pilot III, according to the Garmin web site at www.garmin.com, is D-GPS enabled. That means that it can accept a differential signal from a Garmin differential beacon receiver and from a standard D-GPS receiver using the standard NMEA protocol. The specifications indicate that the accuracy in usually within 15 meters. Nowhere in the specifications does it indicate that the unit can receive the WAAS differential, which improves the position accuracy to within 3 meters.

To double-check my info, I called Garmin support, and was advised that they are D-GPS enabled but do not have WAAS capability.

Dear Capt. Paul:

Can you please give me GPS coordinates for Rabbit Island in Vermilion Bay near Marsh Island and T-Butte Reef in the Gulf west of South Marsh Island?Joseph Steen

Capt. Paul’s Response:

Rabbit Island was a banana shaped island about 1,600 feet (.3 miles) long that was in a ENE to WSW position. The eastern-most part of this island was located at or about N29º 30.636 x W91º 35.722. The western-most part of the island was at or about N29º 30.564 x W91º 35.975. The eastern-most part of the island is about 2.8 miles at a bearing or 254º magnetic from Point Chevreuil. The smaller of the two sections is, I believe, now called Little Rabbit Island.

The original US Geological Survey benchmark was located just SW of the western part of the island in 1985. The marker was at or about N29º 30.540 x W91º 35.985. The concrete pillar with a horizontal brass disk that lists its position was at one time on the SW tip of Rabbit Island. It is now probably underwater, as the island tip has eroded toward the east.

The Tete Butte Reef basically follows the shoreline west of Lighthouse Point at the Southwest Pass of Vermilion Bay. If you were to negotiate through Southwest Pass to Aid To Navigation (ATON) Green No. 7 (a 17-foot high light and marker) at N29° 34.586 x W92° 02.800, and look to the west at a bearing of about 272 degrees magnetic, you would observe a small platform about 1.7 miles from the above ATON and about .3 miles from the shoreline.

That platform is north of the center of the area named Tete Butte Reef. Use caution as the water just west of the pass is only about 6 feet deep, and it gets shallower as you move farther west.

I believe that the eastern-most section of the reef is located at about N29°34.880 x W92° 02.708. The western end is near Tiger Point, at about N29° 32.435’ x W92° 14.960.

There is a southern “bulge” in the reef that is south of Hell Hole Bayou and the Portage Lake canal at the Gulf of Mexico. This section is located at about N29° 35.216 x W92° 06.518. The MLLW water depth in the area is about 7 feet, over the reef about 5 feet. Use caution as there are numerous other oyster reefs in the area.

About Captain Paul Titus 192 Articles
Capt. Paul Titus has been responding to G.P.S questions on LouisianaSportsman.com since 2000. He has been fishing and hunting in Louisiana since 1957. Titus holds a USCG license and conducts instruction courses in the use of GPS for private individuals and government agencies.