Blog module icon

MMWD Blog: Think Blue Marin

Welcome to our blog! Written by staff at MMWD, “Think Blue Marin” explores all things water in south and central Marin—water supplies, conservation, new projects, watershed management, and more.

Need Help?
For tips on subscribing, searching, and commenting, please visit our blog FAQ page.

View All Posts

Aug 21

Oh Rats!

Posted on August 21, 2015 at 10:56 AM by Ann Vallee

by Charlene Burgi

Has your drip system become a chew toy for some critter? Or has the large tomato you prized vanished just before it turned the perfect shade of ripeness? This scenario has all the earmarks of fur-driven trouble—but which furry critter?

My neighbor lamented that their first tomato of the season disappeared. Broccoli next departed from the scene. The hunt was on. Large snap traps were set out in the vegetable garden, and the culprit(s) were soon found. It was neither squirrel nor rabbit, but rats! Four of them were trapped within two days, but not before the row of lettuce disappeared along with more tomatoes and broccoli.

rat damage
 Rat damage
Rats. It appears to be a very bad year for these varmints. They have chewed the rubber seal on the bottom of our garage door to gain entry. My daughter shared they found a wood rat with a broken leg on their front sidewalk in Petaluma. And MMWD received a report about a drip system no longer applying water to the intended plants, after rats chewed random holes to access the water within the tubing. The stories keep coming in, which leads me to believe these mild winters have played an important role in the population surge. And as these rodents search for food and water during the drought, more and more seem to be finding their way into our gardens and homes.

There are three type of rats typically found in California. Norway rats, roof rats, and wood rats all play a role in setting our nerves on edge. They are big, move fast, and carry diseases we don't want to hear about. Rat eradication is a challenge. Unchecked (and who would be checking) rats can have up to six litters a year with more than eight babies per litter. Even the controversial Common Core math will spell out that equals a lot of rats!

Knowing the habits of these rats can help you dispose of them. Roof rats prefer the higher elevations in your home. They can also live in your trees and the tall shrubs of the garden. On the other hand, Norway rats burrow and stay at lower elevations around the home. Wood rats, also known as pack rats, are equally destructive and manage to steal shiny things such as small tools, coins, etc., for their nests. All rats have the ability to chew through wood, wire, pipe, and plastic. Additionally, they are attracted to any food source available; therefore, it is imperative that all food stuffs be secured in metal containers and dog and cat food meals get picked up soon after pets leave their feed stations.

Diligence is the key for eliminating these critters. I prefer using snap traps. Poisons are too risky for me to trust that one of our domestic animals or birds of prey won't be subject to undigested poisons. Live traps also carry a gruesome job. If you trap it, you are responsible for humanely killing it. This means you cannot let it go or drown it. If you are good at playing Whack -A -Mole, this might be an avenue for you to try. No matter the method used, repeating the process over and again is required until all evidence of their presence is gone.

With the bit of research shared here, I leave you with the hope you do not need to deal with such a dilemma. We can only hope this El Niño will help limit population growth in the future! Meanwhile, remain vigilant and watch for the telltale signs these night marauders leave behind.


Keith Bancroft
August 24, 2015 at 8:54 AM
Take care when using any type of rodent trap in/around the garden, as ground-feeding birds (or squirrels, skunks, etc.) may stumble upon them. I cover my garden rat trap with an upside-down pot or other cover, leaving just enough room for a rat to crawl under.
Nancy Hilty
August 29, 2015 at 9:46 PM
We sure do have 'em in Marin. I rented a place in San Anselmo which was much more of a fleabag(literally; my dog, though on oral flea control, started scratching and chewing as she never had before).than it appeared to be---a few tendrils of ivy were coming in around window frames. My supervisor's aide, a good friend, suggested I call the county Vector and Mosquito Control department, which came out and did a very complete survey--I tagged along because it was also a team being taught assessment, and I learned a lot. They found definite signs of rats. I hadn't known that ivy(the big leaf kind with white edges, which develops berries), is a habitat very much favored by rats. They live, eat, and breed in it.. If people have it and think it's decorative, it should be eliminated!! That house was covered with it, as were the fences and the wires were heavy with it. It's certainly all over must have been thought decorative at some point. When I bought a house and had a set of compost bins built, they are unfortunately too near my garage back door, and the whole garage is not critter-proof, being the oldest and un-remodeled part of the house. I was storing oranges, which I get in bulk from my cousin's tree in Vacaville, on open shelves in the garage. All of a sudden I found the insides eaten out. I found a great rat catcher at Orchard Supply Hardware, called a Tomcat(there is another similar brand I forget the name of). These traps look like a big black plastic clothespin and have a very strong spring, so of course should be positioned where children or pets couldn't get at them. The bait(peanut butter worked fine)is placed far back in the trap, so the rat has to go into it . But the way it caught my rats(they were small, but they weren't mice),it simply suffocated them. So all you have to do is walk out to the garbage can and open the trap as you would a clothes pin, squeezing behind the sprung hinge, and the carcass drops out whole--no mess, no need to touch the rat, like the old wooden traps. I used them for about two years, and haven't used them for a while. Somebody told me that rats are smart and won't return to a place they've found dangerous. Good communication systems, I guess! But now you've got me worried about my drip system, because some of my tomatoes are awful this year! Really love your blog! Nancy Hilty
Leo White
December 12, 2015 at 12:21 AM
You have shared nice blog about well known creature. Sometime it become really hard to protect home and garden from these unwanted guests. Two years ago i was just fed up of mouses. They had destructed my backyard, carpets etc. Even they had bitten power wires. I tried every possible traditional way to get rid of them, but nothing worked. Finally i called rodent prevention team. They helped me a lot. You can read about them at-
Anonymous User
March 9, 2017 at 10:24 PM
I use my pellet rifle. 71/73 this season.

Leave your comment

You may log in before leaving your comment,
or submit anonymously