Roof rats (Rattus rattus) are the worst rodent pest in the state of Florida and most abundant. They are an introduced species of rat native to southern Asia. They were brought to America on the first ships to reach the New World and have spread around the world. They are associated with having spread the bubonic plague during the Middle Ages and are also the reservoir host for murine typhus. They are also known as the black rat, gray rat, citrus rat, fruit rat or palm rat.
What do roof rats look like?
Adult rats are 12 -14 inches long and weigh 5-10 oz. Their tail is longer that the head and body length. They are hairless, scaly and their color ranges from black back with a slate gray belly, gray black with lighter gray belly, and brownish gray above with a white or cream colored belly and their body is sleek with prominent eyes and ears.
What do they eat?
Roof rats are omnivores (plant-and animal-eating) but they prefer fruit. They feed on most cultivated fruits and eat many native fruits and nuts. They also feed on pet food, bird seeds in feeders and garbage.
How to they reproduce?
Roof rats reach sexual maturity at 3 to 4 months of age. In Florida, they breed year-round. The gestation period is between 21 to 23 days and each litter can have 5 to 8 pups. Their peak breeding period is in spring and fall and a female roof rat can have 4 or 5 litters per year.
How do I know if I have a rat problem?
Droppings and urine are usually how most people recognize they have a rat problem. Old droppings are gray, dusty, and will crumble. Fresh droppings are black, shiny and putty like. Droppings are long and cylindrical and measure about ••• inches in length. Rats urinate while running, and the streaks are characteristic. The urine will glow under ultraviolet lights and glows blue-white when fresh.
Rats gnaw every day in order to keep their teeth short and sharp. They also gnaw to gain entrance or to get food. Teeth marks on food, wires, building materials, holes in wooden walls, screens, plastic, lead water pipes are also an indication of their presence.
Rats habitually use the same paths. Outside runways are paths about 2-3 inches wide and smooth and indoor runways are usually along walls. Along the runways you will find dark, greasy rubmarks that will appear as black smudges. New rubmarks are soft and will smudge while old ones are brittle and will flake when scratched.
Also a good indication of a rat problem is the sighting of them. Sounds like scratching or squeaking noises can also indicate a problem. Rats are active mostly at night and usually show the greatest activity the first half of the night if food is abundant.
How can I prevent a rat problem?
Rodent proofing your home is a good way to start. Remember that rats can squeeze through cracks ••• inch wide and they are excellent climbers and jumpers. Places to rodent proof are edges of doors, windows, holes where pipes enter buildings, ventilation holes in foundations, roof vents, exhaust fans and eave vents. In order for the rodent proofing to be effective you must block all possible rodent entry points. Inspections and rodent traps will be necessary during the first two weeks of rodent proofing.
Good housekeeping is another way to prevent a rat problem and it needs to be done constantly in order to be effective. Eliminating food, water and harborage for rats can reduce the rodent population. Make sure garbage and rubbish are cleaned up, trees are pruned, properly store food, store pet food and bird seeds in rat proof containers, remove harborages, dry up sources of water, pick fruit and vegetables when ripe so rodents will not feed on them
Trapping and poison baits are other methods of prevention. The traps can be used to eliminate rats where poison bait would be dangerous, to avoid dead rat odors and to eliminate bait-shy rats. Remember whenever a rodenticide is used, safety must be the first consideration. Poison baits must be placed where they are inaccessible to children, pets, livestock and wildlife. In all outdoor situations, tamper proof bait boxes must be used. All rodenticide labels in Florida state that it is illegal to place any poison rodenticide baits where they are accessible to children, pets, livestock or wildlife, unless the bait is contained in a secured, tamper-resistant bait station.
In Florida, many species of snakes help control roof rats. Hawks and owls are also effective on killing them.
Control of rats is not an easy task. Integrated pest management is needed to control these pests. This includes inspections, cultural control (prevention and habitat management), physical control (trapping and exclusion), biological control (predators) and chemical control (rodenticides and repellents). If you think you have a rodent problem contact a pest control professional today.
If you have any questions about rats or pest in general please send them to Yvette@alsmarco.com or call 239-389-1468.
Yvette is a Florida Certified Pest Control Operator in general household pest control and lawn and ornamental spraying. She completed studies in Entomology and Pest Control and holds a Pest Control Technology certificate from the University of Florida. She is a Licensed Landscape Contractor in Collier County and has a Bachelor’s degree in Marketing from Interamerican University of Puerto Rico. Yvette and her husband Al are the owners of Affordable Landscaping Service and Design, LLC. a company that offers Landscaping Design, Lawn Care, Tree Trimming and Pest Control Services.