Rats

Norway Rats (“Brown Rat” or “Sewer Rat”):

• Stocky and larger than Roof Rats
• Large, robust
• Belly color is mostly gray
• Weighs 7 to 18 ounces
• Tail is shorter than its body, dark above and pale below, scaly
• Blunt muzzle
• Ears don’t reach its eyes

Roof Rats (“Black Rat”):

• Slightly smaller than Norway rat
• Sleek, agile
• Belly color is gray to white
• Weighs 5 to 10 ounces
• Tails are longer than their heads and bodies combined, uniformly dark with fine scales
• Pointed muzzle
• Ears are long enough to reach eyes if folded over

Virtually everywhere that human populations have settled

Depends largely on whether it lives in the wild or in captivity:

• 1-2 years in the wild
• Up to 4 years as a pet

Norway Rat:

• Generally found at lower elevations, but can live wherever people live
• When invade buildings, usually remain in the basement or ground floor
• More powerful swimmer
• Larger and more dominant species

Roof Rat:

• Attics, trees, overgrown shrubbery and vines
• Residential/industrial areas with mature landscaping
• Riparian vegetation of riverbanks and streams
• Live and nest above ground in shrubs, trees and dense vegetation such as Ivy
• In buildings, most found in enclosed or elevated spaces such as attics, walls, false ceilings, and cabinets
• Prefers ocean-influenced, warmer climates
• Young rats occasionally confused with a mouse
• Young rats have large heads and feet in proportion to there bodies whereas adult mice are proportionately smaller
• More agile, better climber

Gain entry to structures by gnawing, climbing, jumping, or swimming through sewers and entering through toilets and broken drains

Constantly explore and learn, memorizing locations of pathways, obstacles, food and water, shelter, and features of their environment

Quickly detect and tend to avoid new objects and novel foods for a few days before becoming comfortable

Can squeeze beneath a door with only a 1/2 inch gap

Norway Rat:

• Eat a wide variety of foods, but mostly prefer cereal grains, meats, fish, nuts, and some fruits
• Will travel 100 to 150 feet in diameter in search for food and water, rarely 300 feet from burrows or nests

Roof Rat:

• Eat wide variety of foods, but mostly prefer fruits, nuts, berries, slugs, and snails
• Especially fond of avocados and citrus
• Often eat fruit that is still on a tree, leaving a small hole through which they completely remove the contents of the fruit, leaving only the hollowed-out rind hanging on the tree
• Will travel up to 300 feet for food

No, Rats are active throughout the year

Nocturnal, active mostly at night

Norway RatsRoof Rats: generally 3 to 5 with 5 to 8 in each litter

Norway Rats:

• Burrows found along building foundations, beneath rubbish or woodpiles
• Moist areas in and around gardens and fields
• Nests lined with shredded paper, cloth, or other fibrous material

Roof Rats:

• Prefer to nest in locations off the ground and rarely dig burrows for living quarters if off-the-ground sites exist

• Eat and contaminate food and animal feed
• Containers, packaging materials in which foods and feed are stored
• Gardens, crops, and ornamental plantings
• Damage structures and property
• Transmit parasites and diseases to animals and humans
• Gnawing causes damage to numerous materials, including soft metals such as copper and lead, as well as plastic and wood
• Electrical wires, car wires, doors
• Insulation in walls and ceilings for nesting