Nobody knows exactly how many rats are living in New York City, but in 2014 statisticians estimated their population to be around 2 million.
Since then, rat sightings and complaints to 311 have nearly doubled from 1,397 monthly complaints in July 2014 to 2,676 complaints in July 2021.
Seeing rats in your own neighborhood? Read our article to learn how to get rid of rats outside and what you (and your neighbors) can do to protect your block from an infestation.
Jump to Section:
- Dealing with Rats in New York City
- Where Do Rats Nest Outside?
- Signs of Rats in Your Neighborhood
- How to Get Rid of Rats Outside
- Professional Rat Control in NYC
Dealing with Rats in New York City
Outdoor rats can be a big problem for residents, landlords, and local businesses in New York City’s brownstone neighborhoods.
The most common type of outdoor rat in NYC is the Norway Rat (Rattus norvegicus), which is also known colloquially as the Brown Rat, Street Rat, or Sewer Rat.
Adult rats can reach 20 inches long from head to tail and weigh up to 11 ounces. Yet despite their size, they’re able to squeeze their way through openings as small as 1/2 inch across.
These pests are known for chewing through garbage, stealing food, spreading disease, leaving droppings everywhere, damaging property (including parked cars), and even decreasing property values.
Where Do Rats Nest Outside?
Norway rats prefer to live close to the ground, digging holes and burrows near bushes and other vegetation.
Rat burrows usually have multiple entry points and contain around 3 feet of underground tunnels that can sometimes extend under concrete and buildings.
New York City rats can establish burrows anywhere that has soft dirt at ground level or below, especially around bushes and vegetation. Common sites where rats burrow include:
- Sidewalk planters and tree beds
- Yards in front of and behind buildings
- Planters near outdoor dining sheds
- Empty lots and constructions sites
- Nearby parks and greenways
Aside from burrowing, rats can also set up nests anywhere that can shelter them from predators and weather conditions.
Outdoor clutter, alleyways, and overgrown shrubbery are top choices for NYC rodents, and if they can find a way inside of your building, there are even more choices available for them.
Signs of Rats in Your Neighborhood
Rats are hard to spot due to their careful nature. They don’t like to run around in broad daylight, so you typically won’t see them running around your block unless the infestation has become severe.
But if you pay attention, you can find telltale signs of rats living on your property or in your neighborhood. When the NYC Health Department sends inspectors to monitor rat activity, here are the common signs that they look out for:
- Active burrows
- Fresh tracks
- Fresh droppings
- Gnaw marks
- Runways (dark, greasy marks along walls and worn down paths in grass)
- Excessive garbage, clutter, or dense vegetation where rats can nest
- Live rats
How to Get Rid of Rats Outside
The approach to successful outdoor rat control is different than tackling an indoor rodent problem. For one, outdoor areas are boundless; even if you manage to remove the rats around your building, more will come from neighboring blocks to take over the territory.
Therefore, the key to outdoor rat control is a combination of:
- Controlling the existing population
- Getting rid of their hiding & nesting spots
- Cleaning up other conditions that attract rats.
Effective rat control isn’t achieved by a single resident or landlord—it’s a team effort that requires the cooperation of everyone in your building and on your block to drive rats away for good.
Here are some simple prevention tips for tenants and landlords to protect your neighborhood from New York City rats:
- Clear out clutter or debris from yards, alleyways, and in front of your building
- Keep gardens free of weeds and trash
- Keep tall grasses, bushes, and shrubs at least 6 inches away from buildings
- Trim shrubs and avoid dense or overgrown vegetation
- Use hard plastic or metal trash cans with tight-fitting lids
- Bring garbage cans and bags to the curb as close to pick-up time as possible
- Never leave trash out overnight
- Report any rat sightings, burrows, droppings, or gnaw marks
2. Closing Rat Burrows
Rat burrows are small holes in the ground where rats live and reproduce. Each burrow typically has one main entrance that’s around 2–4 inches wide, as well as side entrances and escape holes.
In the context of New York City neighborhoods, access to food and water most commonly comes in the form of garbage left on sidewalks and alleyways, although gardens, yards, and outdoor dining setups are also attractive spots for rats to set up their burrows.
- If you find a rat burrow, close it by filling it with soil and tamping down with a shovel.
- Burrows in cracked or broken sidewalks may need to be filled with metal filler and cement.
- Pest control professionals may fill active burrows with things to kill the rats inside, such as natural rodenticides or dry ice, before closing them.
Dry ice in particular is very effective for outdoor rat control. When placed into rat burrows, dry ice sublimates into carbon dioxide which fills the burrow and suffocates any rats inside. New York City officials started using this method in 2018 to exterminate large numbers of rats infesting public parks.
Another product used by MMPC and other pest control professionals for eliminating rats and their burrows is BurrowRX. This machine pumps carbon monoxide through their tunnels and nesting areas, which humanely kills any rats inside within minutes.
The carbon monoxide smoke is colored so that the licensed applicator can see if the gas leaks through any other holes that might be connected to the burrow. If so, those holes are also be blocked and closed.
3. Physical Barriers (Exclusion)
Exclusion, one of the cornerstones of an Integrated Pest Management (IPM) approach, involves installing physical barriers to shut the rats out.
To prevent rats from being able to get inside buildings, city officials recommend sealing all holes and cracks in foundations, walls, floors, underneath doors, and around windows. Some examples of materials used for sealing include:
- Sheet metal
- Door sweeps
- Pipe collars
- Wire screens and steel mesh
- Expansion foam
Patches of empty dirt in gardens, planters, and tree beds should be fitted with a top layer of steel mesh or a screen to stop rats from burrowing beneath the soil.
Using a caulking gun, seal cracks and small holes with caulk or cement. Any gap that’s larger than half an inch is big enough for a rat to crawl through. For larger gaps and holes, fill them with cement or expansion foam before covering with steel mesh and seal with cement.
Doors with gaps should be fitted with metal door sweeps to prevent rats from squeezing through underneath. If you see gnaw marks, install sheet metal plates on the bottom of the door.
Lastly, seal any pipes leading into walls with pipe collars and cover any drains or vents with metal screens.
4. Rodenticides & Baiting
Baiting is the most effective and preferred method of long-term population control for outdoor rats.
This method uses rodenticide bait (in the form of blocks or pastes) placed inside of tamper-proof boxes. The boxes, called bait stations, are designed to allow rodents to get in and eat the poisoned bait, while keeping it safely out of reach from pets and children.
At MMPC, our exterior rat baiting program uses anticoagulant bait blocks that are formulated to effectively attract and exterminate rats and other rodents.
Rather than killing the target immediately, rodenticides used for exterior rat baiting are designed to be slow-acting—rats usually die after 4 to 6 days of taking the poisoned bait. There are two reasons for this:
- Rats are cautious and clever animals, and will avoid taking bait if they see other rats dying from it. Slow-acting rodenticides make it harder for them to associate bait stations with danger.
- Rats take food back to their nests to feed their young. Since they’re not immediately lethal, the poisoned bait can be shared with other rats to effectively whittle down large outdoor rat populations.
In NYC, you are allowed to place rodent bait on your property if you live in your own home without tenants. However, commercial and multi-unit property owners must hire a licensed pest control company to do it.
Bait stations should be placed in the perimeter of buildings near common access points such as:
- Doors, windows, and other entry points
- Trash cans
- Compost bins
- Sheds and outbuildings
- Pipes and vents
Professional Rat Control in NYC
While there’s a lot you can do to protect your neighborhood from rats, sometimes you may need to call in the help of professionals. A good pest control company will help you inspect, monitor, and manage outdoor rat infestations.
At MMPC, we’ll work together with you and your neighbors to implement a combination of pest control techniques and IPM strategies, including:
- Rat baiting and trapping
- Locating and closing burrows
- Reducing or eliminating harborage areas
- Installing rodent exclusion mesh
- Identifying and sealing building entry points
The goal of MMPC’s Integrated Pest Management (IPM) program is to provide residents with effective, long-term outdoor rat control by addressing the conditions that allow rodents to thrive, resulting in a steady decline in pest populations.
IPM is endorsed by the EPA as a safe, eco-friendly approach to pest control because it minimizes the application of pesticides, using them only in areas with active rat infestations.
Have questions about how to get rid of rats outside your building?
Need help with closing burrows, rodent exclusion, or rat baiting?
MMPC is a team of licensed pest experts with over 25 years of experience helping our fellow New Yorkers and local communities solve outdoor rat problems.
Use our contact form or call us at (212) 219-8218 to ask us questions, request a quote, or schedule a service.