America deals with two rats. The Norway rat digs burrows and works at ground level; the roof rat — Rattus rattus — climbs. In coastal Mobile, the climber wins. A warm-winter port town with grain elevators, working wharves, and a live-oak canopy over half its streets is about as close to purpose-built roof rat habitat as North America offers, and the species has held this waterfront since sailing ships tied up at the river.

Four local realities keep the pressure on:

• The port feeds the population. Grain terminals, warehouses, and continuous cargo traffic mean the waterfront never runs out of rats or calories — and the surrounding neighborhoods absorb the overflow, from downtown lofts out through Midtown.
• The canopy is a highway. Roof rats rarely cross open ground. They travel live-oak limbs, fence rails, and service lines — above your head, at dusk — and any branch resting on the roof is a bridge with an open gate.
• Builder gaps are the front door. A roof rat needs a hole about the size of a quarter. Soffit returns, gable vents, roof-to-fascia joints, and the gap where the AC chase enters the attic are the classic entries — look for greasy rub marks and gnawed soffit corners, the calling cards inspectors read first.
• Mobile yards set the table. Satsumas and kumquats left on the tree, pecans on the ground, bird feeders, and pet food on the porch hold a colony on the block through winter. A hollowed-out satsuma with the rind intact is practically a roof rat signature around here.

And the species call matters. A Norway rat problem is a ground game — burrows, slab gaps, crawl-space doors. A roof rat problem is a roofline game. An operator who mixes them up puts traps and seals in all the wrong places, which is why the inspection comes first.

Rodent work done right in Mobile is mostly carpentry-adjacent detective work. On a good first visit, expect the operator to cover:

• The roofline, on a ladder. Soffit returns, gable vents, fascia joints, plumbing flashing, and the AC chase — every quarter-sized gap gets found and mapped. If nobody climbs anything, you got a doorstep quote, not an inspection.
• The attic read. Droppings (roof rat pellets run about half an inch, pointed at the ends), greasy rub marks along rafters, tunnels in the insulation, and gnaw damage — including wiring, which is the genuinely scary part of an attic infestation.
• The species call. Roof rat or Norway rat — the operator should tell you which and show you why, because trap placement, bait strategy, and exclusion points all change with the answer.
• Trapping before baiting indoors. Poison inside an attic means rats dying inside walls — and you’ll smell the mistake for weeks. Careful operators trap and remove indoors, and reserve any rodenticide for locked, tamper-resistant stations outside, placed away from kids and pets.
• Exclusion — the actual fix. Stainless mesh, sealed soffit returns, capped vents, sealed chases. Trapping empties the attic; exclusion keeps it empty. A plan without exclusion is a plan to see the operator again every fall.
• The attractant walk. Pick up fallen citrus and pecans, rethink the bird feeder, store pet food in metal, and trim limbs several feet off the roofline. It’s homework, but it’s the cheap half of the solution.

One honest caveat: no yard in a canopy neighborhood is ever rat-proof — the goal is a sealed house and an unattractive yard, and that combination genuinely works.

• “Roof rat or Norway rat — and how do you know?” The answer should come with evidence: dropping shape, rub-mark height, entry locations. The species determines the whole plan, so a shrug here ends the interview.
• “What’s your ADAI license number?” Every legitimate Alabama operator has one, and the Pesticide Management Section in Montgomery — (334) 240-7240 — can confirm it. A pro expects the question.
• “Where are they getting in?” Ask to see the gap — the soffit return, the gable vent, the chase. If the plan doesn’t name entry points, it isn’t an exclusion plan; it’s a trap subscription.
• “Trap-first or bait-first indoors — and why?” There’s a right answer inside a house: trap and remove, so nothing dies in a wall void. How an operator handles this question tells you how they think.
• “What do I change outside?” Fruit pickup, feeder placement, limb trimming, pet food storage. An operator who hands you the attractant homework is solving the problem, not renting it back to you.