Scratching and running sounds above the ceiling at night, bits of debris falling from above, and gnawed fruit on trees: you are most likely dealing with the roof rat (Rattus rattus), the climbing rat that lives up high while the Norway rat lives down low.
This article is part of the rodent library, and it complements the Norway rat article and the Rats and Rodents article.
Size: a sleek rat slimmer than the Norway rat, with a tail longer than its body, large ears and prominent eyes.
Place: it prefers high places such as drop ceilings, attics, tops of walls and trees close to the building.
Entry: it climbs cables, pipes and branches to enter through roof and ventilation openings, not from the ground like the others.
Sign: running sounds in the ceiling at night, gnawing on wires and tree bark, and spindle-shaped droppings along high runways.
The rule: place stations up high along its runways, trim branches touching the building, and seal roof openings.
How do you recognize it?
- Size: slimmer than the Norway rat, weighing between 150 and 250 grams.
- Ears: large and prominent, and they cover the eye if folded forward.
- Tail: longer than the body, smooth and thin.
- Droppings: smaller and thinner than the Norway rat, with pointed ends.
- Color: black to grayish brown.
Where does it live?
It chooses high, safe places:
- Sheds and drop ceilings: and between ceilings and insulation.
- Palms and trees: it nests among fronds and fruit.
- Fences and wires: it moves along them like aerial roads.
- Feed stores and farms: it prefers fruit, dates and grain.
The damage it causes
- Electrical wires: it gnaws them, causing faults and fires.
- Fruit: it gnaws fruit and dates on trees.
- Insulation: it damages the insulation and contaminates it with urine.
- Diseases: it spreads them through fleas and droppings.
The control plan
- Trim branches: that touch the roof and fences, and cut dry fronds.
- Place bait stations up high: on fences, above ceilings and in sheds along travel paths.
- Traps: in high places and on beams.
- Seal entry points: ventilation, cooling and cable openings.
- Weekly follow-up: and refill the bait according to consumption.
For details, see getting rid of rats and mice.
How does it move through a building?
- Upper routes: wires, pipes, fences and branches.
- Times: active at night and at heights.
- Nests: in the shed, among palm fronds or inside drop ceilings.
- Food: fruit, nuts, dates and grain.
Its special signs
- Gnawed fruit: from the top of the skin.
- Date pits: left hollow high in the trees.
- Sounds above the ceiling: especially during the night.
- Runways on fences: greasy marks on wires and pipes.
The difference between it and the Norway rat
The two are similar in the damage they cause but differ in behavior, which changes the control plan:
- Movement: the roof rat is a skilled climber that jumps and walks along wires and branches, while the Norway rat stays close to the ground.
- Nest: it builds a nest of leaves and rags in the shed or among branches, and rarely digs.
- Food: it prefers fruit, nuts, grain and dates more than meat and scraps.
- Caution: it also avoids new objects, but it moves along fixed high runways, so stations fixed on those runways succeed.
How does it get into the building?
Since it climbs, closed doors do not stop it. Its most common entry points: branches close to the roof or wall, wires and cables running between buildings, uncovered ventilation openings and chimneys, open roof edges, and even rain pipes. After it gets in, it lives between drop ceilings and insulation, making light sounds and quick running at night, especially at dusk and just before dawn.
The most dangerous thing it does: electrical gnawing
All rodents gnaw because their incisors grow continuously, and they need to wear them down. Electrical wires are among the most tempting targets for the roof rat because they are in its path. Gnawing can expose the copper and cause a short circuit or mysterious outages, so it is advised to inspect exposed wires in the shed and have any damage repaired by a qualified electrician.
Simple prevention that reduces its visits
- Trim branches so they stay a reasonable distance from the roof and walls.
- Collect fallen fruit under trees and palms regularly.
- Cover ventilation openings and chimneys with sturdy metal mesh.
- Install metal guards around palm trunks and poles where needed.
- Store grain and feed in metal or thick plastic containers with lids.
And do not forget that cleaning without sealing entry points is not enough, because the rat will come back as long as the way in is open.
When is it most active?
Its activity rises in fruit ripening seasons and after harvest, and in the months when food outside is scarce and it looks for a warm shelter inside buildings. If you notice gnawing on fruit and leftovers under trees, or nests among palm fronds, controlling it will most likely require work both up high and on the ground.
Products from the Orkida store
We prefer locked stations and a plan that combines bait, traps and sealing entry points. We also advise following the dose on the package and placing bait away from children and pets.
- ProCatch Bait Station for Rats and Mice | English-made BULLET Model: a locked, tamper-resistant bait station in which we place the bait away from children and pets, suited to rats and mice along walls and passages.
- ProCatch Medium Bait Station for Rats and Mice | English-made Rascal Model: a medium-sized station for larger rats and outdoor entrances.
- ProCatch Large Bait Station for Rats and Mice | English-made Vanguard Model: a large station for farms, storerooms and open areas where rodents gather in large numbers.
- Ruban Soft Bait for Rats and Mice, 250 g: a wrapped soft bait that attracts mice and is easy to place inside stations, from a specialized international company.
- Rozol Soft Bait for Rodents, 200 g: a soft bait from the international Liphatech, favored by rats and mice and used in stations.
- Catchmaster American Ready-to-Use Glue Traps for Mice and Crawling Insects | 72 Glue Boards: glue traps for monitoring and light infestations, useful indoors where bait is not wanted.
Frequently asked questions
Why do I only hear it above the ceiling?
Because it prefers heights and enters through branches, fences and cables.
Does it really gnaw wires?
Yes, its teeth grow continuously and it needs to gnaw, and wires are among its targets.
Does it affect fruit trees?
Yes, it gnaws fruit and spoils dates especially.
Are ground traps enough?
No, because the rat moves up high, so put the stations on fences and ceilings.
How do I know it is in the shed and not in the wall?
If the sounds are above the ceiling and concentrated at night, and the droppings are in the shed near the insulation, it is most likely in the shed. Sounds inside walls may mean a mouse or another rat.
Do I need to replace the insulation after an infestation?
If the insulation is contaminated with urine and droppings, it is best to replace it after cleaning and disinfecting, because it holds odor and germs.
Image credit: Alex O'Neal — Wikimedia Commons (CC BY-SA 2.0)