Boats are moored for long periods of time. Big cockroaches running around on the jetty will come and hide in the crevices of your boat.
When taking supplies onto your boat, cockroaches and cockroach eggs can be secreted in the boxes you get from your suppliers.
Nothing worse that having a German cockroach problem as they multiply profusely. Imagine waking up to cockroaches running over you, your kids or guests at night.
Waterfront properties are also notoriously known to experience rat problems. Apart from not wanting to share your bed with a rodent, they can chew through the wiring and leave you stranded at sea. Rats also carry fleas, the cause of the Black Plague.
An Inspection of your boat will identify these pests and immediate treatment can solve the problems.