Rats! Prevention is the Best Cure!

Imagine my distress to find out while we were gone cruising last winter that another boat on our dock had an unexpected visitor!  Really?   RATS in a US Marina?  First world?  Supposedly rats are a fairly common occurrence, just not one we’d been exposed to except while cruising third world countries.
Obviously rat concerns are why all the cruise lines use gigantic rat guards on all their lines while in port.   I had no idea, but after hearing about the incident on “D” dock, I went back to look at my Key West photos from last winter, sure enough Royal Caribbean ship we watched depart Key West had rat guards on every line that connected to shore.

Royal Caribbean Cruise Line Rat Guards in Key West

While in Bocas Del Toro and other marinas in Guatemala & Panama, we were concerned about rats, but (knock on teak) never had an incident other than the one year I decided to leave rat catcher glue strips on our bow to catch any rats that tried to board.  BIG MISTAKE!  First of all, the rats just run over them and secondly, wind will flip them over and permanently adhere them to your deck creating the biggest gummy sticky mess you ever saw!  P.S.  WD40 will get it off, but GooGone doesn’t begin to start — firsthand knowledge!

While getting Winterlude ready to leave for the summer, we debated and researched rat guard options. Basically, it seems like the only effective rat guards are placed on all lines connected to shore and big enough that the rat can’t just run over or around it – apparently they’re pretty talented acrobats.    But the downside to putting giant plastic bottles or pieces of metal like the cruise ship on our lines is the potential for chafe in a hurricane or storm conditions.
Eventually we decided that the best cure is prevention.  Keep rats off your boat!
We scoured every inch of Winterlude’s deck, anywhere we could think of on our deck that anything could get INSIDE the boat and made sure it was secure.  The information we read said to secure any opening larger than a quarter inch – quarter inch?  Who’s ever heard of a rat that small?   But that means electrical openings, anything & everything.
For example, the chain grabber is secured making sure there’s no access to get inside via the windlass or the chain locker openings.
In addition, we examined all our dorades.  Luckily, we remove the dorades and secure the openings with screw caps when we leave.  The only exceptions are the two dorades over the main cabin – both of which have secure screens in place and one has a solar fan sucking air out while the one across the cabin lets air in (with the screen).  Cross ventilation!   🙂

Check dorades – while they allow airflow, they can also allow access!

Secured for Hurricane Season

The only dorade left intact has a secure screen preventing entry into the main salon.

We all know rats love a good mess, so make sure there are no messy areas left aboard when you leave the boat.   Any food left aboard has the potential to attract them – and don’t be fooled – a rat can eat through heavy plastic containers, maybe not glass and metal, but anything else is suspect.  We’ve seen firsthand the damage caused when rats ate though an Amel 53’s solid teak floorboards in LaCeiba Shipyard, Honduras to get to the food stored underneath!   Don’t leave food aboard!

Clean out all storage areas.  Luckily this is part of our “leave the boat” routine anyway to make sure roaches, ants and other pests aren’t attracted.  So our normal preparation, mopping the floors, cleaning the stove – including oven, sides, behind and beneath, cleaning out the refrigerator and so on pretty much covers the same stuff we’d do to make sure we don’t attract rats.

They also don’t like light, so we figure the dock lights will provide enough light to discourage them at night… of course, the other boat down the dock has the same lights at night, so ….

We’ve done all we can do, and the marina is working on the situation, so hopefully they’ll be eradicated soon.

Our other line of defense is having our caretaker check the boat once a week instead of once a month as in the past.  Hopefully if there are any problems, we’ll catch them sooner before the dang rats have a chance to set up housekeeping, squatting in our floating winter home!

What do you do to make sure rats don’t invite themselves aboard?  Please leave a comment and share.  We haven’t had to deal with this issue for several years now!   Cheers — Jan




  1. Tom McNulty says:

    Wow, what a timely post.
    Just 2 weeks ago I returned from a day sail on Lake Pontchartrain and as six of us were visiting on the dock, a rat ran from the aft end of my boat to the foredeck. I ran to stomp it just as it jumped from the foredeck onto the dock and into some tall grass nearby. I never keep food on my boat as we are day sailors and my boat is by far the cleanest in the marina where we are docked. Since that time, I have researched every rat preventative known to man. I bought a device made by BirdX which emits a high pitched sound and is supposed to keep them away. This device is too annoying to have on unless you are not aboard the vessel. Also, after reading a bit about how rats and mice hate peppermint oil, I purchases 16 ounces of the oil for $65 and have put it all over the boat in every nook and cranny. I haven’t sealed the boat off yet because I didn’t want to trap any inside and have them die in the boat. The only place they can get in is from my vents from the engine compartment. I plan to take care of sealing it off this coming weekend.

    • Hi Tom! Let us know if the Peppermint Oil kept the rats away. Hope all is well with you! Cheers! Jan

      • Tom McNulty says:

        I forgot about this post until your rat update this week. I tried the Bird-x device but ended up discontinuing it. After sealing off the vents, I was successful in keeping them out of the engine compartment and below deck. The peppermint oil is pretty strong when first returning on a hot day but airs out quickly when a hatch and companionway are opened. I think light may attract them. I had a device on my shore power cable that indicates galvanic action. If all is good, it emits a bright green light from an LED. While that light shone in the cockpit I continued to find evidence of critters. I moved the device to the power pole on the dock and no evidence any more.

Speak Your Mind