What map card to use for traverse bay

[Lykins Tr21]

Lowrance Hds units, what is best card for mapping in MI

[thedude]

to my knowledge, Great Lakes topography is all provided by NOAA or USGS and is pretty good all round (its the great lakes so well documented for commercial navigation). All the map providers get their baseline from that source which is pretty good.

That said, you probably don't need to worry too much about 1 brand vs the other. Fish are either relating to shallow structure, spawning flats etc or somewhat transient on the break lines if you are going to realistically target them. Water Temp fluctuates drastically based on wind most of the year and once fish are out of pre-spawn/spawn phases, a current temperature map will probably be more useful than a topo map. For reference, fish will spawn well into July and not uncommon to find them on beds in august. For reference, last weekend shallow water was 60 and low 50s in the open/deep parts. It was low 40s by wed and back up to 55 sunday. It could back up to 60 or 38 depending which way the wind blows in the next few days.


Also, you can see 25' down. You can see most of the productive water on google maps.