RedactedNarrative: Watercraft #1 was unoccupied and tied to the dock. Watercraft #2 was backing out of a boat slip when the operator put the throttle in forward and started to slowly drive. Operator #2 said she reached down to swat a horsefly and accidentally pushed the throttle which increased the speed. The bow ring from WC #2 hit the motor cover of WC #1, causing minor/moderate damage. During the impact, WC #1 had also been pushed down which caused a dock ring to leave a scratch on the right side of WC #1. Life jackets were on board WC #2, but it's unknown if they were being worn. There were no injuries. It is unknown if alcohol was a factor. There was some damage to both boats.