Whenever funds are moved from a non-custodial wallet to an exchange (similar to the one you posted), then it usually signifies that a whale has moved their funds to an exchange to trade it aka sell it off which might move the market downward depend on the volume he/she is offloading. It's also called an inflow. Then when it's the other way round - whales withdrawing funds from exchange accounts to personal wallets, signifies an outflow which further means that they've accumulated the much they can and are now holding their stash.

I'd like to point out that you shouldn't rely too much on those whale alerts as they're often not accurate so it's best to just use them for information purposes only and not let them contribute to your trade bias.