GPS Speed Reading vs. Fishfinder

[KaGee]

Is there really any need for speed on a fishfinder as long as I have it on my GPS?

I am more interested in trolling speeds.

 

[swist]

Re: GPS Speed Reading vs. Fishfinder

Using aviation terms, GPS speed is "ground speed" (speed over land). Fishfinder or or other speed derived from a mechanical instrument on the boat is "air speed" (speed relative to the water). If there is any current, the two may differ considerably.

As a silly examp[e if you are going 2 kts into a 2kt current, your GPS speed will read zero (you ain't going nowhere) and your speedometer will read 2 kts.

Ground speed is usually more useful as it will tell you your progress from point A to point B, but for trolling you are more interested in speed relative to the current.

 

[Dunaruna]

Re: GPS Speed Reading vs. Fishfinder

[colour=blue]For trolling, I prefer to set the speed to suit the 'action' of the lure.

 

[Boatist]

Re: GPS Speed Reading vs. Fishfinder

Fish finder paddle wheel speed sensor very good at speed thru the water. I use it a lot when trolling for Salmon. I find I catch more fish at about 3.3 Miles per hour.

Some rivers we back troll and it is the most affective way to catch Salmon. River current may be 4.5 Miles per hour. Set trolling speed at 3.3 Miles per hour. Now your lure is spinning, jigging or what ever and slowly drifting down stream. Salmon in the stream facing up current get ticked off at this pesky little spinner headed right in it face and strikes it.

Even in slow current where can not back troll different water speed for different tempertures work better. Once you find the right speed and depth you will catch a lot of fish.

One other place I use the Paddle wheel water speed is finding a place to anchor when fishing for sturgeon. Strong current I fish shallow water, Lighter current can go deeper. Also when anchored lets you know early when the current is slowing and the tide is about to change. One of the best times to catch Sturgeon.

Over the ground speed nothing works better than GPS.

 

[KaGee]

Re: GPS Speed Reading vs. Fishfinder

So what you are saying is, I really need both right?
The paddlewheel for trolling and the GPS for navigation speed. :/

 

[Boatist]

Re: GPS Speed Reading vs. Fishfinder

Keith
Really only you can tell if you need both. If you troll lakes where there is really no current GPS should work fine.

I hate all the transducers, paddle wheel, temperature prob ect on the transom but at times they can help you find a pattern the fish will bight on.