What goes pitter-patter in the night at your house?

Scratch, scratch, slither, slither, tap, tap. What is lurking in your walls and eaves and attic space? Our urban landscapes are home to a whole host of things that can find their way into your home.

Today, we talk about how to get rid of them and how to prevent them from selecting your home to take up residence.

Raccoons

It’s the season for mama and baby in the attic, walls or chimney. Sometimes when they’re in the chimney, “It’s a standoff,” says Charles Fisk of Area Wide Chimney Sweep. “They don’t like us.”

If they’re in the chimney, the babies sound like birds but without the wings flapping. Inside the attic or walls, you’ll hear scratching.

Make sure the chimney cap is on and does not have a hole in the screen; ditto for the roof vents. Also, make sure there are no soft spots in the wood around your house to make it easier for them to get in and that all holes are plugged up. Raccoons are very determined to get inside, however. They will tear open a roof.

“You’re not going to stop them if they want in your house,” says Gary Bauhof of Austin’s Wildlife Removal Services.

Different companies handle what to do with a raccoon differently. Some relocate, others kill them, saying relocation is cruel because they are used to living in an urban environment, not in the country. Dealing with most rodents and mammals that need to be trapped is usually a $300-$700 job.

Squirrels

They are very similar to raccoons, but they usually don’t create the hole. “They pretty much find a little hole and move in,” says Rich Hahn, owner of A All Animal Control. Making sure you don’t have holes in the walls, roof or eaves, or access to vents and chimneys, will make your home unattractive to squirrels. Also get rid of bird feeders to avoid a squirrel and raccoon problem.

Opossums

Unlike raccoons and squirrels, opossums tend to only stay for a few days and then move on, Hahn says. You can prevent visits from opossums, raccoons and squirrels as well mice and rats by putting away dog and cat food and other foods. “You can help them not make a living by giving them dog food and cat food,” Bauhof says.

Rats

Rats are good climbers, just like squirrels, and they can have a litter every 30 days. If you have a hole the size of your thumb, they can get inside. They can be trapped.

Mice

Mice are not climbers, and they will come in on the ground level. They only need a hole that is about the size of the end of a No. 2 pencil, or about 1/4 inch. You have to address how they are getting in. It’s better to trap them and seal up the hole than throw out bait and have them die inside the house.

Armadillos and feral hogs

In some of our urban areas, people are having a problem with these critters tearing up yards. They are looking for grubs in your grass and will move on to the next house if you don’t have grubs.

Bats

Sometimes bats get in between the brick and the wall and create a colony there. They like a space where air flows through, so if you seal up those spaces, they won’t be able to get in.

Bees

Bees can find a crack of about 3/8 of an inch and build a hive inside your wall. They are looking for a cavern about 6 inches by 9 inches by 6 inches. Bird bath pedestals and garden pottery are popular beehive spaces outside. Don’t spray water on the hive or try to spray it with insecticide. You’ll just injure or kill a handful of bees and make the others very, very mad. There could be 100,000 bees in a hive, and that could turn deadly, says Walter Schumacher of Central Texas Bee Removal. Don’t seal up the crack before you remove the bees first or else you’ll have angry bees inside your wall and angry bees outside trying to get back to their hive. Schumacher will come and remove the bees for a donation and then relocate them to a new, safer hive.

Wasps

Wasps like to hang out in protected spaces like eaves and awnings. With wasps, you can knock down the nest, but you have to be careful, says Jerry Naiser, owner of Real Green Pest Control and Lawn Care. Wasps sense when you are afraid, so try not to put that vibe out there when you knock down the nest. Sprays only work if you hit the nest itself and every wasp inside.

Termites

Don’t stack your firewood against the foundation of your house unless you want to invite termites to move inside. Also, if you have a wood deck, make sure it is treated wood. Termites live underground and make mud tunnels up the foundation to reach the wood of the house. Inside the house, look for specks of dirt on the walls or pinholes or soft spots in the wall that are hollow where there should be a wood stud. You also will find them under bathtubs because there’s no concrete under there, just dirt. There are specific sprays that are designed for termites. Some of the newer high-tech sprays make their jaws immobile, killing them through starvation.

Carpenter ants

These are similar to termites, in that they will eat your house, but they leave sawdust around windows and doors and on the floor because they don’t actually fully consume the wood. Carpenter ants come in through cracks and on trees and bushes. They are looking for water. Specific sprays can be used.

Pharaoh ants, Rover ants or sugar ants

These ants are looking for water, yes, but also for sugar. You can prevent them from wanting to be in your house by keeping sinks clean. They especially like toothpaste, so make sure to fully rinse the sink and put the cap back on the tube. They also like to hang out in electrical outlets, especially in air conditioners. They don’t do damage or bite. They are just gross. You can spray for them or bait your lawn to kill the colony that will eventually come in your house.

Fire ants

These mainly stay outside but are a painful nuisance. If they do come inside, they are coming in through cracks and crevices. You need to make sure the colony is active before you can treat it. Some treatments only take care of the worker ants. You want to make sure you’re using the kind that either creates a disease within the colony or gets passed from one ant to another during grooming. Fire ants can take several treatments to kill the mounds.

Roaches

Roaches typically get inside your home in food. Spray to get rid of them and then keep your house clean to not create an inviting habitat.

Bed bugs

They typically come into the house through hitching a ride in a suitcase when you travel and through used sofas and mattresses. When you travel, lift up the mattress and look for fecal matter or blood spots and holes in the mattress, recommends Jason Napolski, president of A-Tex Pest Management. They are difficult to get rid of and the sprays don’t really work. Your house has to be sealed and heated up to kill them, and that can cost $300-$400 a room or $1 a square foot depending on the size of your house.

Mosquitoes

They need standing water to breed, so don’t provide it to them. Empty that kiddie pool and make sure that the sprinkler system is not creating a wet spot in the yard. Look out for wet leaves, because it doesn’t take much water for mosquitoes to breed in it. After it rains, shake out tarps and empty planter bottoms and rain gutters. If you have a pond, make sure you have mosquito fish to eat the larva. Put larvicide in rain barrels. They don’t breed in chlorinated swimming pools, though. Karyn Brown of Mosquito Squad used to have a ton of mosquitoes in her yard where her five children didn’t want to play. She can spray a barrier in the grass and plants around the yard that will kill mosquitoes in your yard and prevent them from coming into the yard, though mosquitoes generally don’t fly far.

Spiders

Normal garden spiders would not be a problem if they didn’t attract other things like larger spiders such as the poisonous brown recluse and scorpions, both of which eat small spiders. Spiders also point to a insect problem, because after all, they’d rather be outside than inside unless you’re providing a rich food source. There are specific spider sprays.

Scorpions

Scorpions love to hide in the attic and in lights and in your shoes. They are seeking a heat source and spiders to eat. Sprays sometimes don’t work on them, and if you stomp on a mother scorpion, she might have 30 tiny babies that can survive in the treads of your shoes. Avoid them wanting to come into your home by getting rid of the spiders inside and knocking back vegetation around the perimeter of your house. You can spray to create a barrier, but if they are already inside, then they won’t want to come out. Often sticky traps will work.

Snakes

Snakes don’t really want to be in your house. They just want the mice or rats that are inside. You can put sulfur power or moth balls around your house to make them not want to enter. Snakes are great climbers and can come into the attic just like any rodent, so keep it sealed. Bauhof says 99 percent of the time it’s not a rattlesnake, even though everyone calls and says it is. That 1 percent is always shocking.

What to spray and when to spray

There were a lot of different opinions on insecticides, but not everything natural is nontoxic and not everything synthetic is toxic, Naiser reminds. You can find out what the spray’s ld50 or lc50 rating is. That stands for lethal dose for 50 percent of the test population or lethal concentration for half of the test population, and the lower the number, the worse it is. For example, table salt has a ld50 of 3,320, but gasoline has an ld50 of 50. All insecticides are regulated by the Federal Insecticide, Fungicide and Rodenticide Act. Exterminators are licensed by the Texas Department of Agriculture, so be sure to ask before they spray.