Trees that provide a habitat to bats and an abundance of bugs—their main food source—will attract bats to your yard. Because the North American landscape has changed so much in recent years, bats have a harder time finding trees with cavities to shelter in. If your yard has a dead or dying tree with a lot of sun exposure, bats will likely be drawn to it because trees with those features are less common.

It can be difficult to know what type of animal is in your attic until you see it. But several clues can help you narrow down the suspects:

• Sounds: Smaller animals like rats and mice make scurrying and tapping/gnawing sounds. Larger animals like raccoons and opossums make louder clambering noises. Also, note when animals are noisy: Squirrels are active during the day, while rats are busiest at night.

• Droppings: Rats and mice leave small, rice-shaped droppings (the rat’s version is significantly larger). Bigger droppings belong to larger critters like raccoons. As long as you’re not squeamish, an image search can help you identify what you’re seeing in your attic.

When in doubt, take photos of damage or other evidence and show them to an experienced pest control pro.

Identifying the specific animal running on your roof at night can be challenging without direct observation. Common nocturnal roof visitors include raccoons, squirrels, opossums, and rats. Raccoons are bigger and can create heavy thumping sounds. Squirrels are agile and may produce rapid scurrying noises. Opossums tend to move stealthily with less noise. Rats can make scratching or gnawing sounds. To determine the culprit, look for signs like footprints, droppings, or damaged areas near the roof. For accurate identification, consult a pest control professional or set up wildlife cameras near potential entry points.

Woodpeckers may seek out homes with aluminum siding or tin roofs because these surfaces echo their drumming. Homes with wood siding are more frequently targeted as roosting areas or for food sources. If you have insects living in the exposed wood in your home, the birds are likely looking for a snack, in which case your best option is to hire an exterminator.