Mysterious hump appears in Callander Bay, NOT april fools

I know this will appear like an April Fools joke but it's not.

Back in 2017 I got this screenshot of Callander Bay from Navionics:



The other day I was browsing navionics and noticed a hump in the middle of Callander Bay:



I'm baffled it wasn't showing back in 2017.

My question is whether this hump exists or was it charted from bad data?

In sonar charts they use user uploaded sonar logs. I'm not sure what kind of verification they do (maybe data from more than 1 source has to match?). If they don't really verify it, it could be that someone had a bad setup and coupled with Navionics not having much data for that area, it made it all the way to official product. Or the hump is there and it just wasn't on original government charts which they used as a starting point.

its a ghost shoal, every year the damn rocks seem to move and trick boaters.

I just wanna fish it

Was thinking the same thing

Is it a hump or a depression?

It shows as a hump. If you look on the right of the pic, there is a shoal missing from near the pipeline. They probably just moved it over.

As WTFish said it's updated information from user updated data most likely. The old way of lake mapping was based on a lot of guesswork.

I have the setup in question and can comment on this.

When you get home and connect to a network, your data is uploaded to Navionics' site.

Most of my logs are rejected. If your data differs too much, it's tossed. If you have data on land, it's tossed. So for this hump to appear is just baffling to me.

I have awesome logs of the pickerel river and they haven't been rejected, nor have they been added to the webapp. I'm guessing they're waiting on more data...

Was thinking the same thing

x2

I bet some old timer has been fishing that shoal for years and laughing at the fact that no map shows it. Lol...Until now.

Facts

And just like that, the hump vanishes once again;

http://webapp.navionics.com/#boating@13&key=y%7CayGdbpcN

priceless!

about 10 years ago I was fishing an area I had never been before on nip, I tend to go real slow and watch the depth finder as my partner keeps an eye out front in virgin territory, it went from 14ft to 3 on the depth finder, I immediately rammed it in neutral, whether it was the speed change or whatever "bang" a 36" muskie hit my lure and jumped straight out of the water, we gently bumped into the rock just as we netted the fish, it was mayhem in 10 seconds but a great memory. never caught a damn thing there since! lol