Rattus rattus and Rattus norvegicus have travelled the food trade for centuries. Norway rats arrived in Australia with the colonial fleet; roof rats arrived earlier on Indonesian and Pacific shipping. Both species shaped the food-storage architecture, the public-health surveillance framework, and the Australian audit standards that food premises now operate under. Rats are not just a pest. They are the species the audit framework is built around.

Norway rat (Rattus norvegicus) is the larger and ground-oriented species. Body 18 to 25 cm; tail shorter than body; small ears; blunt snout; reddish-brown to grey-brown back; lighter underbelly. Burrows in soil-perimeter zones; nests in ground-level voids, sub-floor cavities, and dock-seal gaps. Dominant in temperate urban zones and warehouse perimeters. Roof rat (Rattus rattus) is the smaller and climber-oriented species. Body 16 to 20 cm; tail longer than body; large ears; pointed snout; black to grey-brown back; lighter or grey underbelly. Climbs walls, runs rafters, nests in false ceilings, roof voids, and elevated commercial structures. Dominant in tropical and subtropical zones and in any site with elevated runways.

Vector pathways differ by species and by site. Salmonella through urine and droppings on food contact surfaces is the dominant food-zone pathway and the reason HACCP, SQF, BRCGS, and WQA standards treat live rat presence as a critical non-conformance. Leptospirosis through urine in damp environments and water-adjacent runs is the occupational pathway pesties working sub-floor and waterway-adjacent sites have to manage; it is reportable in several Australian states. Hantavirus through aerosolised dust from old droppings is the cleanup-vector risk that drives HEPA-cleanup discipline before any service work in roof voids and dry-store cavities. Rat-bite Fever, while low-frequency, is a real bite-pathway that supports the welfare-grade snap-trap-inside-station spec on sites where children, pets, or non-target wildlife can encounter the trap.

Reproduction is the reason small program failures rebound fast. Both species reach sexual maturity at five to seven weeks and produce litters of six to twelve every three to four weeks across a fertile season. A single missed harbourage on a food-zone site can produce a 30-rat colony inside a quarter. The audit framework's emphasis on trend-line documentation across the reporting period, not just point-in-time station status, reflects the recruitment biology. The program is judged on the trend, not the last check.

Anticoagulant resistance has become a 2026 program-design issue across Australian rats. Field evidence across 2024 and 2025 shows resistance signal in Norway rats at multiple urban-warehouse and commercial-precinct sites, and in roof rats at scattered hospitality and agribusiness sites. The implication is that single-active rodenticide programs lose reliability over time and that Advanced IPM design (multi-modal placement, snap and trap layers, sensor-led intervention, lure rotation, and resistance-aware bait selection where rodenticide is used) is the durable design. Pest IT supplies the field evidence and the resistance-management adjustment.

The audit framework is what links the species science to the program documentation. HACCP, SQF, BRCGS, and WQA assessors look for documented program activity over time. Station counts by zone, maintenance logs by station, intervention records per fire-up, trend lines over reporting periods, and the licence-renewal evidence required for regulated sites are the deliverable. State Public Health Acts add the residential-and-hospitality reportability layer (NSW, QLD, VIC, WA, SA, TAS, NT, ACT each have their own frame). Pest IT supplies the state-by-state framework.

Pest IT supplies the systems, consumables, training, and design support that fit the species science to a real site. The Viper signature range covers the rodent station mix; the MinkPolice trap monitoring layer carries the remote-program data layer. For the kit, the placement, and the audit documentation pack, the Rodent Stations and Traps collection holds the kit. For the small-rodent counterpart species and the plague-year framing, the Mice collection holds the mouse story. Trade pricing applies to every approved trade account. Pest IT's Knowledge Hub holds the program training depth.