Post-Monsoon Wildlife Audit: 7 Spots in Your Tucson Home Where Wildlife Just Moved In

By the middle of September, Tucson’s monsoon has largely spent itself. The washes have run, the humidity is dropping, and the yard looks like it survived. That is exactly the moment most homeowners stop paying attention — and exactly the moment wildlife problems become permanent.

Everything that moved during monsoon was looking for the same three things: water, food, and shelter. Water is drying up fast. Food is thinning out. Shelter is the only one left, and your house is the best shelter for a mile in any direction. Animals that spent July and August passing through your property are now deciding whether to stay for the winter.

The audit below takes about an hour. Seven spots, in the order we most often find something. Do it now, in September, while an eviction is still simple.

Why September Is the Audit Month

Monsoon storms do two things that set up fall problems. They open new entry points — washing out soil under fence lines, warping trim, lifting flashing, and eroding the grade around foundations. And they drive a rodent boom whose survivors need somewhere to overwinter.

Add falling nighttime temperatures and the calculation changes for every animal in the neighborhood. A packrat that was perfectly happy under a creosote bush in July starts eyeing your garage in September. A rattlesnake that hunted your yard all monsoon starts looking for a rock pile or a wall void to shelter in as it moves toward denning.

Catch it in September and you are removing one animal. Catch it in January and you are removing a nest, repairing chewed wiring, and cleaning up months of droppings.

The 7-Spot Audit

1. The attic and roofline

Start at the top, because this is where the expensive problems live. From the ground, walk the full perimeter and look up: gaps where the fascia meets the roof deck, lifted or missing tiles, unscreened gable and soffit vents, and any gap where a roofline changes pitch. Monsoon wind and rain routinely open these.

Then go into the attic with a flashlight. You are looking for droppings, shredded insulation pulled into a pile, dark greasy rub marks along beams, and daylight visible at the edges. Bats leave small dark droppings that crumble; packrats leave larger pellets and drag nesting material. Either one is a call, not a DIY project — and bat work in particular is legally restricted to the October 1 through May 1 window.

2. Garage door corners and weather seals

The garage is the single most common indoor entry point we get called for in Tucson. The bottom corners of the door are the weak spot: the seal compresses and cracks over a hot summer, and the two triangular gaps at either end almost never close properly.

Close the door, go inside, and turn off the lights. Any daylight you can see is a gap something can use. A young rattlesnake needs about a quarter inch. Scorpions and toads need far less. Replace the bottom seal, add corner inserts, and check the side jamb weatherstripping while you are there.

3. Block-wall weep holes and drainage gaps

Weep holes exist so water can escape a block wall, and they work — but they are also open tunnels at ground level. Walk your entire wall line and count them. Then look at every point where the wall crosses a drainage path, because monsoon runoff scours these out into openings big enough to walk through.

Cover weep holes with quarter-inch galvanized hardware cloth, which blocks snakes and rodents while still letting water through. For washed-out drainage crossings, you need a barrier that passes water and stops animals — that usually means a mesh insert sized to the channel rather than simply filling the gap.

4. Under sheds, decks, and equipment pads

Anything with a dark, dry, protected void underneath is prime overwintering habitat. Sheds on skids, raised decks, AC condenser pads, and hot tub surrounds all qualify. Get low with a flashlight and look for worn entry paths in the dirt, scat, shed skin, or a hollowed-out depression where an animal has been bedding.

Skunks and javelina both favor these spaces, and rattlesnakes will use them as a cool retreat. Screening the perimeter of a shed or deck with buried hardware cloth is the permanent fix, but only after you are certain nothing is currently inside — sealing an animal in is worse than leaving the gap open.

5. Packrat middens in landscaping and vehicles

A packrat midden looks like a messy pile of sticks, cactus pads, and debris, usually tucked against a wall, under a prickly pear, or beneath a parked vehicle. They are unmistakable once you know what you are looking at, and they matter for two reasons.

First, packrats chew wiring — engine bay harnesses, irrigation lines, and low-voltage landscape cable are all common casualties, and vehicle wiring repairs get expensive quickly. Second, and more important, packrats are the primary food source for rattlesnakes in this area. A midden on your property is an open invitation. Remove middens with gloves and a respirator, or have them removed, and address whatever is feeding the population.

6. Pool equipment and irrigation valve boxes

These are small, damp, shaded enclosures — which is to say, ideal. Pop the lids on your irrigation valve boxes and look before you reach in, every single time. We get calls every year from homeowners who put a hand into a valve box without looking.

Around pool equipment, check the pad itself, the gap behind the pump, and any conduit penetration into the wall. Sonoran Desert toads in particular congregate around pool decks and equipment where there is reliable moisture, and they remain a serious hazard to dogs well past the end of monsoon.

7. Chimney, dryer vents, and exhaust penetrations

Finish with the penetrations most people never think about. An uncapped chimney is an open shaft; birds, bats, and the occasional raccoon all use them. Dryer vents, bathroom exhausts, and range hood outlets have flapper covers that stick open once they warp or fill with lint.

Every one of these needs a proper cap or screen rated for the purpose. Do not simply stuff them — blocked exhausts are a fire and carbon monoxide risk. Use vent covers designed to exclude wildlife while maintaining airflow.

Signs Something Already Moved In

As you work through the seven spots, you are looking for evidence as much as openings. The most reliable indicators:

• Droppings — the clearest signal, and the species is usually identifiable from size and shape.
• Sound — scratching or scurrying overhead at dawn and dusk, or a high chittering at night.
• Odor — a persistent musky or ammonia smell near a wall or ceiling.
• Rub marks and worn paths — greasy dark smudges on beams, or packed trails in the dirt leading to a gap.
• Nesting material — insulation, shredded paper, or plant matter that has been dragged and piled.
• Shed skin — a snake has been sheltering nearby, even if it is not there now.

What to Fix Yourself and What to Call About

Sealing weep holes, replacing a garage door seal, capping a dryer vent, and clearing a midden are all reasonable homeowner jobs with basic tools and hardware cloth. Do them now, before the temperature drops further.

Call a professional if you find droppings or hear activity in the attic or a wall void, if you suspect bats, if you find a snake or shed skin near the house, or if something has already established under a shed or deck. Sealing an occupied space traps the animal inside, where it dies and creates a far worse problem than the one you started with. The order matters: confirm it is empty, then seal.

Get Your Post-Monsoon Inspection on the Books

The homeowners who make it through a Tucson winter without a wildlife problem are usually the ones who looked in September. If your audit turns up something you would rather not handle — or you would rather have someone who does this daily walk the property with you — Animal Experts has been solving these problems in Tucson since 1991. Give us a call and we will inspect the full structure, identify every active entry point, and put together a plan to close it properly.