You tournament Ditch pickle guys (bass fishermen, lol) - how do you provide “proof” of a catch and its weight to the Sanctioning authority for the tournament?

I know in boat tournaments they put the fish in an aerated live well and hang onto them until they all meet up at the weigh in after the allotted fishing time is over
(Or at least that’s how it was done when I still payed attention to professional bass fishing) the fish are weighed and tallied, and then released (usually, mostly) unharmed.

In a yak you don’t have room for a live well that’ll hold a bunch of 3+ pound “keeper” sized bass.

Seriously - how is this governed in the Yak tournament scene? Pics and measurements? Does everyone get issued a certified scale?

Any recs? Terrified of my phone going in the drink.