Before the sun sets, rat No. 1 appears. Brown and beady-eyed, it skulks out of a ramshackle shed and onto a concrete trough. In the waning daylight, it drinks and washes in the rainwater, oblivious to the car that's pulled up a few feet away.
Greg Gurri Glass surveys the scene from his 5-year-old Chevy and smiles. The steel mesh traps aren't even unloaded yet, and already the rats are out. His job tonight will be easier.
"This is a pretty amazing place when the sun goes down," he says, walking through the Reservoir Hill alley.
Shattered glass, animal excrement and trash form an ugly patchwork here. An empty vodka bottle rolls down the pavement like a tumbleweed. And flies circle rats, dead and squashed, near a chain-link fence. Even the stray cats avoid them.
In five minutes, Dr. Glass, a Hopkins researcher who has studied rats for 10 years, counts 30 live ones in this alley bordered by Linden and Brookfield avenues. But that's only a fraction of how many have burrowed here.
"There are probably more rats than people in Maryland," he says matter-of-factly. "Very few alleys don't have them."
Not only are there more rats, but they are appearing in city neighborhoods and suburbs where they weren't seen before and spreading diseases of greater concern to health officials.
In Maryland, rat complaints rose significantly in recent years. Baltimore alone logged nearly 3,600 last year, an increase of more than 40 percent from 1991. In Anne Arundel County, reports of rat problems have more than doubled in two years.
And d-CON, a leading manufacturer of rodent traps and bait, recently ranked Baltimore eighth among cities in sales of its rodenticides.
"Everyone associates them with the inner city," says Dr. Glass. "They're certainly there, but you can find them anywhere now. Some of the ritziest horse farms around Baltimore have rats."
Budget cuts in eradication programs, warmer winters (excluding last year's) and half-hearted recycling efforts have helped the common Norway rat -- a brown furry animal that can reproduce 12 offspring in 21 days -- thrive.
Besides the property damage they do -- chewing through wood, cinder block and aluminum -- rats, which once spread bubonic plague, are carriers of disease, the most menacing of which may be hantavirus.
Although the Centers for Disease Control and Prevention now believe the Norway rat -- Rattus norvegicus -- is not a carrier of the respiratory illness that killed more than 30 people in the Southwest since May, these rodents have spread less deadly forms traced to the area.
Three cases of a hantavirus called Baltimore rat virus were detected in the city, and 25 people, exposed by inhaling airborne particles of rat dust, urine or feces, were found to be infected in the late '80s, says Dr. Glass.
Although no one died from the renal and pulmonary illness, one patient suffered chronic kidney disease and wound up on dialysis.
'Reservoir of disease'
"Rats are one of the major reservoirs of disease," Dr. Glass says. "But a lot of the illnesses they cause are difficult to diagnose. . . . We simply don't know how many people get ill from rodent-borne diseases."
The search for an answer brings Dr. Glass, a blond cherub of a man with a rhinestone in his ear, to this alley on a warm spring night.
While teens blithely play pick-up basketball across the street, he researches whether the hantavirus first found in this alley some 13 years ago still exists here.
Navigating around soiled diapers, pizza boxes and egg shells, he places 12 cage-like traps baited with peanut butter by burrows.
He's eager to finish before sundown because rats are resistant anything introduced after dark. But the scar on his hand from a rat bite years ago reminds him to move gingerly through rat-infested alleys.
"It's getting to be about the right time," he says, setting the next-to-last cage near a dead evergreen.
The sign on a telephone pole tells him someone has been here before him. "Attention," it reads, "this block is under inspection for rats." The city's Rat Rubout program is treating for rats here, but there are still plenty to go around.
Jotting down the date, weather and alley conditions in his record book, Dr. Glass chortles when asked whether this book doubles as a guest registry for rats.
"They sign in," he says, "but they don't sign out."
A former whiskey distributorship in Southwest Baltimore serves as the nerve center for the city's war on rats. Except for the picture on the front door -- a rat with a slash mark through it -- Rat Rubout headquarters is a nondescript place. Even the drums filled with poison look as much like janitorial supplies as the stuff that causes disease-ridden rodents to meet their end.
Work has gotten tougher here since the program began in the late '60s. Initially, there was a staff of 90. Now 24 people cover the entire city.
"It takes us longer to get back to do follow-up on the sites we've treated," says Donna A. Johnson, who after 14 years as general superintendent of Rat Rubout recently transferred to zoning. "Sometimes by the time we get there, it's almost like starting over."
But that's better than in Montgomery County.
"We don't have a program," says Stephen Haynes, an environmental health specialist with the county. "We have two people."
And yet it's not the workload that's most frustrating.
"I don't see the finer side of human nature," Ms. Johnson says, examining a trash-strewn yard in Northwest Baltimore with burrows the size of baseballs. "I don't see the practical side. . . . It's so unnecessary and unfortunate for humans to do this to themselves. Why do they find it acceptable to live like this?"
This year's hard winter -- usually a deterrent to the rat population -- had an unfortunate byproduct: It kept many crews off the streets. And trash went uncollected in icy alleys for days, giving rats an ample food supply. Although conventional wisdom says cold weather reduces the rodent population, Ms. Johnson believes that may not happen this year.
Neither does John Kreuger.
60 rats in a day
He recently called Rat Rubout after counting 60 rats in the yard of his Violetville home in a single day.
For a time, the vermin had so infested his surroundings that he carried a baseball bat in his own back yard and encouraged his wife to keep their 5-month-old daughter and toy poodle out of the yard.
"I'm a grown man," says Mr. Kreuger, 33, a warehouse worker. "There are not a whole lot of things I'm afraid of, but rats are one of them."
After doing research and buying bait, he has seen the problem improve, although he's not sure for how long.
"I've lived in the city all my life," he says. "I've never seen a problem like this before."
Across town in stately Guilford, John Boland copes, too.
Last summer, he thought he saw a squirrel drinking from his fish pond. Looking again, he realized it was a rat.
After several other sightings of the same -- or some other -- rat, Mr. Boland, 58, hired an exterminator. But he's skeptical about whether he's actually licked the problem.
"I've lived here for 18 years, and that was the first time I'd seen one," he says. "But once they show up, they don't go away."
And miles away in Harford County, registered sanitarian Leonard Walinski has gone from fielding 210 complaints in 1991 to nearly 290 last year.
"More people are moving into the county," he says. "They over-feed their bird feeders; they don't cover their trash cans."
In response to reduced help from the city or counties, neighborhood associations have tried to fill the void by organizing alley clean-ups, offering discounts on metal trash cans and handing out fliers about rats.
Residents of Reservoir Hill, for example, recently met and discussed going door-to-door to collect money for a private trash company and exterminator.
The rat boom has been good for one business: pest control. Dennis Butler, sales manager of Orkin in Baltimore, says work is up at least 25 percent in the past three years.
"Recycling programs aren't helping much," he says. "It's fine if people rinse out tin cans and milk bottles. But a lot of people aren't doing that. A rat's sense of smell is 20 or 30 times better than ours. That smell attracts them right to your doorstep."
Rats are often ruled by their stomachs, and one of the best ways to deter them is to take away their food source, he says. That means putting trash in metal cans with lids, removing cat and dog food from outside and cleaning up a pet's droppings, which rats will eat.
"Occasionally, you have to stand back and start thinking like a rat," says Mr. Butler. "Where would I go? What would I do? You have to find the darkest, gloomiest corner. That's where rats set up home."
'Sleek-looking animals'
By 8 p.m., the rats are out in Reservoir Hill.
"Boy, they are nice," Dr. Glass says, watching one scurry toward a burrow with a graham cracker in its mouth. "In some alleys, the rats are chewed up, but these are sleek-looking animals."
For hours, he has watched through his cracked windshield as rats have tried (some successfully, some not) to outsmart the crude machines made for their destruction. He's smiled after hearing the "clink" that tells him another rat has been caught.
In his mind, the rats have personalities. There's the alpha rat, "a big old fat male with a chewed-up tail;" the crippled rat that drags its left front paw; the "West Side Story" rats which, like Jets and Sharks, fight a turf battle over a plastic trash can.
Dr. Glass, an assistant professor at Johns Hopkins University's School of Hygiene and Public Health, conducts crude population studies, counting how many rats he sees from his car in five minutes. Each time, the number hovers around 30, substantially below his record of 50. By his estimate, though, some 100 rats call this alley home.
"Rats are breeders," he says. They are weaned in two weeks, can reproduce by 1 1/2 months and can produce a litter of 12 in three weeks.
"You can see why wiping them out is not a reasonable goal," he says. "I can understand people's revulsion to them. But they're not great evil creatures. They're tough animals living under tough conditions. And they've survived."
Dennis McLain disagrees. He lives there on Linden Avenue, where the rat problem is so bad he refuses to put his trash there. Instead, he walks two blocks with his trash bags to a corner bin.
"As the night progresses, it's just going to get worse," says Mr. McLain, 36, a roofer. "The best thing you can do is stay away from here."
In his younger days, Dr. Glass would stay here until the early morning, tracking the time these rats spent eating, drinking, fighting and copulating.
But tonight his work is nearly done. He travels down the alley one last time, collecting his catch. Picking up the metal handles, the rats let out high-pitched squeals.
"Shh, shh. It's OK, fella," he says, soothing them the way one would a frightened child. "That sound is, 'I want to rip your face off.' "
Altogether, eight rats have taken the bait. That's a worthwhile evening, he says, covering them in trash bags and putting them in his trunk. They will travel back to his Hopkins lab where tomorrow he will anesthetize, measure and weigh them, and draw blood from their hearts. Several days later, he'll learn nearly half have Baltimore rat virus, confirming that the virus has persisted here for more than a decade.
When he has drawn enough blood to store for years of research, he'll give these rats a final injection. Within 10 seconds, they'll be dead.
"I really don't like killing them," he says. "But what can I do? People don't have a problem with you taking the rats away. They would take issue with you bringing them back."