Why Rat Populations Will Grow During the COVID-19 Pandemic

Closing restaurants and asking people to shelter in place had an unexpected impact on rodent behavior and feeding patterns. In several major U.S. cities, experts reported increased daytime sightings as rodents searched for new food sources after nightlife trash and restaurant waste declined.

In New Orleans’ French Quarter, for example, early lockdowns brought highly visible swarms of rodents shortly after the COVID-19 closures. For pests that had relied on tourist litter and nightly refuse (in cities from New York to Seattle), food scarcity forced new foraging strategies—including riskier daytime activity and shifts toward household trash.

Why Lockdowns Changed Rat Behavior

With fewer people out and less commercial waste, urban rodents sought alternative calories. The UK’s National Pest Technicians Association (NPTA) warned that shuttered venues could incubate bolder, larger rodent populations in empty buildings. As restaurant bins emptied, nearby neighborhoods saw increased pressure on domestic waste streams.

Across multiple U.S. cities—Seattle, New York, New Orleans—lockdown periods coincided with spikes in sightings and service calls.

“Rat Wars” and Cannibalism Under Stress

Food scarcity stresses colonies and can escalate aggression and cannibalism. As rodentologist Bobby Corrigan noted, muricide (rat-on-rat killing) becomes more common when stable food sources disappear. View his April 16, 2020 tweet here: twitter.com/rodentologist/status/1250913867645018112.

Rodents Are Masters of Adaptation

Urban rodents use keen olfaction to locate calories and can breach weak points—thin plastics, gaps around doors, and fabric—quickly. Their adaptability explains their ubiquity—and why broad environmental changes (like lockdowns) rapidly shift their behavior.

Opportunity for Proactive Control

Empty downtowns gave cities a window to deploy aggressive sanitation and control with fewer public-space constraints. New Orleans, for instance, intensified efforts in commercial corridors during closures to suppress population booms.

Scarcity can also make traps more effective: hungry rodents take more risks around baited devices, while in severe shortages colonies self-regulate through competition.

Why Household Rodent Pressure Matters

Hungry, roaming rodents threaten homes and businesses. Beyond structural damage (gnawed wood and wiring that can increase fire risk), rodents can carry numerous pathogens. While research on specific risks evolves, good exclusion and hygiene remain fundamental.

Lockdown-Era Homeproofing Checklist

• Seal exterior gaps ≥ 1/4″ around pipes, utilities, foundations, doors, and vents.
• Reduce interior harborage: declutter basements, garages, and utility rooms.
• Secure food sources: store in rodent-proof containers; clean spills promptly.
• Maintain waste: keep bins closed, liners intact, and pickup areas clean.
• Deploy traps where activity is evident (along walls, near travel routes, behind appliances).

Cities Using Empty Streets to Their Advantage

Municipal leaders, including in New Orleans, leveraged reduced foot traffic to concentrate control efforts in commercial districts and public spaces—reducing near-term pressure on vulnerable populations and neighborhoods.

Bottom Line

Your best defense is disciplined sanitation, airtight storage, sealed entry points, and reliable trapping. The A24 automatic rat & mouse trap provides constant, humane control without toxins and automatically resets for continuous protection.