Why Seattle Is One of the Most Rat-Infested Cities in America

Our city’s hyper construction is causing more than traffic issues. Experts believe it’s one reason our city is ranking high as a rodent-infested town, and getting rid of the pests is anything but easy
One longer term solution to the rat problems is to target their reproductive systems, a novel approach to controlling a species so prolific one pair can produce 15,000 progeny a year.

This article appears in print in the March 2018 issueClick here to subscribe.

Great food, mild weather and a prime waterfront location have long guaranteed Seattle a spot among America’s top cities. Unfortunately, that appeal also extends to some less desirable neighbors, so much so that the Seattle-Tacoma region placed ninth on a 2017 ranking of America’s top 50 rodent-infested towns; specifically, rats. “Rats have been a problem forever in Seattle,” says Jeff Weier, technical director for Sprague Pest Solutions, a Tacoma-based company that proudly notes “90 years of kicking pests in the tail.” 

Weier saw rats when he moved here in the ’80s, but lately, it seems the problem has grown. “I’m not sure exactly why,” he says, though he speculates that development plays a role. “There used to be open fields and lots everywhere and they’re all being filled in with homes,” he says. In other words, rodents that once lived here have essentially been displaced. “And, of course, when we build in their environment, we invite them in, basically.

One of the city’s biggest construction projects—the 2-mile tunnel being constructed beneath the Alaskan Way Viaduct to replace that roadway—offers one answer. Before Bertha, the tunnel boring machine, broke ground in 2013, Sprague Pest Solutions reportedly ran a mobile-billboard campaign warning residents of a pending “ratpocalypse,” predicting a scourge of displaced critters heading indoors. After all, that’s exactly what happened in Boston, whose signature Big Dig displaced so many pests, one newspaper ran a 2002 story titled “The Year of the Rat.”

Seattle city officials took note and passed new legislation modeled after longstanding programs in Kirkland and Shoreline that require developers to initiate pest abatement programs prior to demolition of any buildings, residential or commercial. That legislation took effect in 2017. “What that means is they’ve got to call somebody like me to go out to the property and set up a rodent control program,” says Öland, which means setting up from six to 10 poisonous bait traps around the property. “Your normal house, my house, might get normally three bait stations put outside,” he says, “but on a rodent abatement program, you want to knock out all of the rats—and fast.” 

By controlling rats prior to demolition, they won’t find new homes in your neighbor’s house or yard. “It’s really easy, it’s very inexpensive, it’s really cost effective, and you won’t be a jerk to your neighbors.” 

Of course, not everyone is excited about the “bait and kill” option for rat control. Even if you have no aversion to killing rats, you might not want to potentially expose other animals to poison.

Sean Met, who runs a one-man wildlife management operation, A Wildlife Pro, in Seattle, has a different approach. “For most people, the problem is that rats are getting inside,” says Met. He focuses on identifying entry points into homes and then sealing up gaps to encourage rodents, who are perpetually seeking shelter, to take up residence elsewhere. “Rats can come across some powerlines very easily,” says Met, who also suggests other strategies to keep rats at bay, including trimming hedges and trees, eschewing chicken coops and limiting compost to rodent-proof bins, although the long-term solution lies in keeping the property secure. (Others suggested keeping trash in dumpsters placed on the curb, picking fallen fruit from the yard, moving pet food inside and keeping doors closed, in particular, the garage door, which Öland described as “the biggest hole in your house.”)

Met considers his approach unique in that he’s trying to find a permanent solution to somebody’s rat problem rather than securing repeat business. He’s also not a fan of the poison deployed by other pest control companies, which might effectively target rodents but also harms other species, for example, owls and other raptors that unwittingly feed on poisoned prey. 


It’s a theory echoed by Erik Öland (aka “the rodent guy” to clients), whose company, Puget Sound Rodent Exclusion Specialist, has been hunting down rats for the past eight years. “We’ve all seen the movies,” says Öland of film scenes with rats scurrying through sewers or making house calls via toilets. “The rat didn’t fall down in the toilet,” he says. “It climbed up out of the sewer. And so, when you’ve got big, heavy machinery and they’re tearing up the streets and what not, then all of the rats that are in that given area are going to scatter,” he says, recalling the scores of panicked clients who’ve called since the reconstruction of Capitol Hill’s 23rd Avenue corridor.

Seattle’s rodent problem—once primarily confined to the Norway rat, which burrows underground—has become worse as a secondary rat species, the roof rat, has become a more important player. “The roof rat lives high,” says Weier of this treetop-dwelling species. “We’ve had situations where they live in the rafters of a building and come down and feed on food in the building and never end up on the ground,” he says, adding that roof rats probably once sheltered in all the blackberry bushes around town. “Now those blackberry thickets are gone.”

No one may know exactly how many rats live in the city, but there’s one thing most Seattleites would like to know: how to get rid of them. Rats, like most pests, are survivors and driven by a need for food and shelter, as are humans. But with half the city, it seems, under construction, how much worse will our rat problem become, and what can we do about it?

One longer-term solution to the rat problem is to target their reproductive systems, a novel approach to controlling a species so prolific that one pair can produce 15,000 progeny in a year. This is the thought behind ContraPest, a liquid formula that brings on infertility in rodents. The product—not yet available in Seattle—was initially tested in a rat-infested trash room in New York’s Grand Central Station, where it reduced rodent populations by 46 percent in 12 weeks.  

“That was one of our first documented trials ,” says biologist Loretta Mayer, Ph.D., the CEO, chair and cofounder of SenesTech, an Arizona-based company behind the brand. Now, Mayer is sometimes called “Dr. Rat” in New York City, which emerged as an early testing ground when Mayer and SenesTech’s chief research officer and cofounder, Cheryl Dyer, Ph.D., were asked by New York’s metro transit authority to take their product from the laboratory and into the subway. 

Subsequent trials have taken place in Chicago, North Carolina, Hawaii and Somerville, Massachusetts, outside Boston, which reported a “significant” drop in rat sightings after distributing rat-resistant trash cans, pest abatement services and SenesTech’s rodent fertility treatments. There are challenges to moving from a lab to uncontrolled spaces, but the regimen still reduces populations by 30–47 percent in three months. Meanwhile, SenesTech is developing a solid version of its formula—which currently exists as a sweet liquid formula highly attractive to sugar- and fat-loving rats—to better suit a range of ecologies and climates, while scaling operations to sate growing demand in the 49 states and Washington, D.C., where ContraPest is currently registered. (The group is expecting registration in its 50th state, California, to become official sometime in 2018.)

Regardless, Mayer and her team—who hope to eventually bring their product to Seattle and other cities—remain driven by a holistic, long-term view. “We’ve been killing them for centuries, in every way imaginable,” says Mayer, describing an ages-old battle that’s involved everything from poison to dry ice to audio repellents to, more creatively, dispatching teams of feral cats and rat terrier dogs to do the job. SenesTech believes it is offering a more sustainable option that will suppress rodent populations in the long run. “The only way to do that is to target their reproduction,” says Mayer. 

Those working in the field are also eager to try something new, although years of fighting one of the world’s most adaptable creatures has bred a healthy skepticism. Wildlife Pro’s Met expressed cautious optimism, particularly regarding ContraPest’s claim not to harm other species. “It’d be the best-case scenario,” he says. “Then, it’s just about getting it into enough hands so that it can replace poison.” 

“It’s intriguing,” agrees Weier of Sprague Pest Solutions. “We’re probably going to try it in some places, but I don’t know if it’s the panacea for everything,” he says, adding that a 40 percent reduction won’t make much difference to a breeding population. (Mayer maintains that the goal is to reduce populations rather than completely eliminate rats; eliminating them could lead to a problem with mice, which are the natural prey of rats.)

While the city awaits a high-tech solution to the rat problem, Seattle’s rat control experts continue to abide by timeworn methods. “Nothing has yet to beat good old-fashioned hard work and inspection,” says Öland, likening his job to detective work as he climbs through rafters and underneath houses, finding and fixing gaps that rats could use to squeeze their way inside. New gadgets, including remote censors and infrared cameras, are waiting in the wings, but, for him, nothing surpasses this rather straightforward procedure, which also involves setting Victor snap traps, a similarly enduring, century-old brand. “I had one guy ask me, ‘Well, why don’t you bust out the black light and get all CSI on it?’” he recalls with a laugh. “In reality, I use my eyeballs and that’s what I’m going to do.

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