Object Tracking Component Selection

I am having difficulty finding the appropriate hardware for my specific project. I want to track an object that is 100-200 ft away from my boat on the water in the dark. The goal is to track it with a light so I can see it. Below is a daytime picture of the objects I want to track for clarification.

I don't think any of the sensors I have found on google would be a good fit for this application due the fact these objects are on the water, in the dark and 100-200 ft away from the boat. It is possible to mount some device in the boards that a sensor can track I am just having trouble finding what device and sensor combination to use.

Thank you for your help

Isn't what you are after a RADAR to find the object? Then the RADAR needs to send info to the light tracking hardware.