French to English Tech/Engineering Ships, Sailing, Maritime

Hello

Docking in an African port and how much it costs, with no other helpful context

Navires de longueur supérieure à 165 m et sans ***propulseur***

so what is a propulseur?

If it is a propeller, then what could a big vessel have instead of propellers?

That's what I don't get. Or does it means without using its own thrust to dock?

Thanks in advance