To maintain healthy watersheds, we must consider all the creatures that inhabit them, from the salmon in the streams, to the mountain lions roaming the hills. And yes, even black rats that are commonly sighted at night skittering along utility lines, or in the garden eating fruits and vegetables that have fallen to the ground. These loathed creatures are commonly eradicated with the help of rodenticides, but many times those toxins can jeopardize the health of our local natural resources. That’s why using integrated pest management (IPM) techniques can help save your garden and your watershed.
Understanding the black rat is the first step toward gaining the upper hand against them. Also known as the roof rat, this subspecies arrived in the Americas from early sailing ships traveling the world’s oceans. Found along the lower East Coast, Pacific Coast, and the Hawaiian Islands, the black rat prefers warmer climates and is less adaptable than other species of rat. Black rats most commonly take shelter and hide in densely vegetated fences and gardens that offer a variety of food options. Although these rats prefer an assortment of fruits and nuts, they are still omnivores and will feed on almost anything in order to survive. Scavenging usually begins around sunset, as these rodents are known to be nocturnal. The black rat is also color blind, so it relies on other senses to navigate around cities. Their whiskers and tails that are as long as their bodies help them maintain exceptional balance along backyard fences.
Once a black rat has moved into an area and feels comfortable, it can begin to reproduce rather quickly. With three or more litters of five to eight young per year, it is essential to control these rodents before they become unmanageable. If you begin to notice these creatures in or around your home and want to keep them from eating your hard earned harvests each year, follow these few tips to help manage your garden:
- Prune dense bushes in your yard, as these rodents prefer this type of vegetation and will often be found housed in such places.
- Cut back trees, specifically citrus trees that are one of the black rat’s favorite, so that their branches are not touching other nearby trees, fences, or buildings.
- Remove any pre- or post-harvest fruits and nuts that have fallen to the ground.
- Plant mint, known to be distasteful and odorous to rats and a beneficial and natural way to keep them out of the garden.
- Remove inviting structures such as wood piles.
Don’t use rodenticides to kill rats! Using alternative strategies, like integrative pest management, is important in keeping not only our watersheds clean and healthy, but also children, small pets, and other wildlife that may be killed or become seriously ill from coming into contact with these poisons. Poisons used to control rats leach into the ground or enter the food chain when they are consumed by predators who feed on these rats for survival. Over twenty-five species in California have been found poisoned by rodenticides. These animals include other small mammals, owls, raptors, foxes, weasels, raccoons, bears, and many more precious species. Rather than finding the quickest, most simple solution to a rodent problem, please consider the affects that those solutions may have on the surrounding environment and choose a more sustainable way to manage pests.