This notification is sent within a minute of a catch! It means the trap has been activated and a rodent has been caught. You should empty your trap as soon as possible. The alert will continue displaying within the app until you have emptied and restarted the trap.
You will receive a low battery notification when your trap’s power falls below 10% and it’s time to insert new batteries. The trap may shock less effectively once the battery power is low, so it’s important to change them soon.