Crawling Around with Baltimore Street Rats
The “urban ecosystem” serves as a research lab for scientist Gregory Glass, who studies the lives of the Charm City’s rats
- By Abigail Tucker
- Smithsonian.com, November 18, 2009, Subscribe
A trio of tiny rat statuettes stands sentinel in the center of Gregory Glass’s desk. The shelves above are stuffed with rat necropsy records and block-by-block population analyses. Huge, humming freezers in the lab across the hall are chockfull of rodent odds and ends.
Now Glass, a professor at the Johns Hopkins Bloomberg School of Public Health, leads me out of his building and into the streets of Baltimore for a bit of impromptu fieldwork. He asks that I leave my jewelry and purse behind; after all these years of tramping the alleys in the rougher parts of town, the disease ecologist still gets nervous around sunset. Yet mostly he enjoys observing the “urban ecosystem,” which, he says, is just as worthy of study as wilder areas, and maybe even more so: as savannas and rainforests shrink, cities grow, becoming a dominant habitat.
“This is what the natural environment looks like for most people,” Glass says, as we enter a narrow passage behind a block of row houses. Some backyards are orderly and clean, others are heaped with garbage. I promptly step in something mushy. Glass frowns down at my flimsy shoes.
Luckily we don’t have to walk far to find what we’re looking for.
“Right at the base of that plywood door? There’s your rat hole,” Glass says, pointing at a neatly gnawed archway. “You couldn’t draw a cartoon better than that. And they’ll graze on this grass right here.”
Glass has been following the secret lives of wild Norway rats – otherwise known as brown rats, wharf rats, or, most evocatively, sewer rats -- for more than two decades now, but Baltimore has been a national hotspot for rat studies for well over half a century. The research push began during World War II, when thousands of troops in the South Pacific came down with the rat-carried tsutsugamushi disease, and the Allies also feared that the Germans and Japanese would release rats to spread the plague. Rats were wreaking havoc on the home front, too, as Christine Keiner notes in her 2005 article in the academic journal Endeavor. Rats can chew through wire and even steel, obliterating infrastructure. Rodent-related damage cost the country an estimated $200 million in 1942 alone. Rat bites were reaching record highs in some areas.
Worst of all, one of the only tried-and-true rat poisons –an extract from the bulb of the Mediterranean red squill plant–was suddenly unavailable, because the Axis powers had blockaded the Mediterranean. Scientists scrambled to find a chemical substitute.
At that point, relatively little was known about the habits of Norway rats, which are beefy (they can reach the length of a house cat), blunt-faced, foul-smelling but surprisingly smart creatures that carry a plethora of nasty bacteria, viruses and parasites. They are native to Southeast Asia, but smuggled themselves aboard ships bound for North America and practically everywhere else, subsisting, in large part, on our garbage. They thrived in aging East Coast cities like New York and Baltimore.
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Comments (16)
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In the small backyard of my Baltimore row house lives 6 rats. They are large enough to trip the sensor on my flood lights.
If you do not hear and recognize the noise a rat makes, then you have not lived long enough in Baltimore.
The rats were easy to trap, and it takes months before they are replaced with new residents.
Posted by AJ on September 18,2011 | 11:58 PM
Re rat size - we lived in an old in Buffalo in 1976 and the rats in the basement were big and bold. We had a little terrier and some of the rats were bigger than the dog. One of them was a faun color, which was even more surprising to me than the size.
The number one spot we see wild rats in Baltimore is the Travel Plaza. Not the Greyhound side but the parking lot where the Chinatown buses drop off and pick up. There are some very bold rats I'm always pleased to see are doing well. There's tons of trash available and lots of places to hide.
We've had pet rats for the last twenty years or so and they make wonderful pets. I've had several that loved to sit on my shoulder while I write, bruxing and keeping me company. I only wish they didn't have such a short lifespan.
Posted by Georgiana on November 29,2010 | 10:25 PM
I run a rescue for domestic rats. They are nothing like the wild rats. They talk about rats biting and disease. But the problem with that scenario is that a rat does not salivate and most of disease are in the saliva in witch the rat have little to none. We can get more diseases from a bite from a cat, dog, or even ourselves. They are miss understood. A rat only goes where there is food for them and we make the messes that the rat live in not them. If it was not for the mess that we make the rats would not be there. The rats are smart and has a better sense of smell than a dog. I having as many rats as I have had past though my rescue and I am sure that they have a soul. They are loyal and show unconditional love more than many people. They will morned at the loss of a cage mate as we would at a lose of a love one. Look at them in a different way, I have and have been blessed with their love.
Posted by Clark on February 13,2010 | 07:51 PM
Instead of trying to kill clever rats with poison pellets why aren't "the powers that be" working on a rodent birth control pellet? Rats aren't at all stupid. They know to avoid that laced food that just killed their kin and the dog screaming with pain because the poison is a liquid activated acid that kills by liquifying the contents of the body cavity, or little kid who's mistaken it for yummy food when it's parents weren't paying attention at the park.
Posted by Shannon on January 24,2010 | 12:40 AM
you lose all credibility as either a scientist or a journalist when you state that rats can be as large as housecats.
you apparently have the typical imagination of a completely non-objective observer telling bar-room stories. this can't happen.
my rats are healthier and eat better and live longer than any street rat, and although i would love to see one grow to that size, it is just not going to happen. when they're overfed, they become obese, not giant.
in the wild, they rarely live 18 months; in captivity, they often live as long as 3 years, with a few exceptions which live a bit longer.
if you'd like to argue this point, please just show me some evidence; if not, maybe you should correct your article.
-bp
Posted by bill price on January 23,2010 | 12:28 PM
Why do they always say norway rats can reach the length of a house cat? If this was true,why has no one ever seen one that big on the news? The reason is simple,it's a myth and it's a shame it shows up here.
The average length of a norway rat is six inches and they might weigh a pound. They also wash themselves,so they really do not smell bad.
Posted by DM on January 22,2010 | 11:59 PM
I live in urban Baltimore. Concerning vegetable gardening, what I've done is grow a large crop of peppermint all around the backyard and am pleased to say that in the last three years I have not seen one rat bite on my backyard tomatoes. The peppermint idea came to me while I was studying a well established herbal book written by Maude Grieve. Also, I've read that rats will do almost anything to get to oil of rhodium. If there are appropriate cages to capture them in, I would strongly suggest the scientist try coaxing them in the traps with this oil. Of course, the scientists are probably already aware of the affinity of rats for this oil. I hope I have helped someone with my comments.
Sincerely,
Karma
Posted by Karma Finney on December 5,2009 | 10:07 PM
While traveling in Rome last year we were up early getting a taxi to a favorite tourist site when a huge rat appeared in the street near us. I was very happy to get into the taxi and shut the door. I wouldn't want to be any closer than I was to THAT particular Rat!
Posted by Marla Dahlk on December 3,2009 | 12:51 PM
I have currently a very bold female brown rat frequenting my back garden. She makes fascinating watching - a highly intelligent social mammal. I guess it wouldn't take much to get her to the point of being tame enough to approach. In terms of rat control, however, I've seen very little to compete with the effectiveness of a couple of jack russels doing what comes naturally.
Posted by Juliet on December 1,2009 | 08:08 AM
This piece reminds me of my first personal encounter with a rat. Many years ago, I was delivering newspapers in Des Moines, Iowa. Traveling along a city street in the sultry early morning hours of a summer day, a scurrying creature moved across the road. It stopped mid-street, turned toward me, and stared. I recognized it for what it was, and was struck by its size, and the penetrating nature of its gaze.
Posted by magendie on November 27,2009 | 09:15 AM
A couple summers ago, I was sitting outside at a local Baltimore eatery, when someone screamed, "Rat!" We all picked our feet up, the rat ran thru the eating area and on his way. We all put our feet down and went on our way of eating our lunch.
Sad, isn't it? You just get so use to these vermin co-habitating in your city.
Posted by suesue on November 25,2009 | 10:39 AM
During a very posh hotel's renovations the staff were moved to an imrpovised dining room in the basement. Thus one morning I found myself hunched over toast and coffee while not 3 meters away sat a small rat, munching a crust. We eyed each other and finished our breakfasts.
Posted by Shir-El on November 24,2009 | 03:00 PM
Some years ago in Portland, Oregon one of my daughters was given a tame white rat. A few days later she presented us with a clutch of little rats. Most of them were bi-color, grey on the front quarter, white behind. They were quite tame, but gave quite a start to some of my husband's friends whle in their cups, when they trotted out from under the couch.
Posted by Mazine Watts on November 23,2009 | 07:31 PM
Last week I saw a program on rats--I am inpressed with the guys, but prefer to remain at a distance, thank you. There are rats in Africa that have been trained to detect land mines!! Did you know that rats can tread water for three days? Open REFRIGERATORS!! Have excellent problem solving skills--and are excellent jumpers. My dear little cat is an excellent mouser, but is quite small-a rate would probably catch her!
Posted by Elaine Parker on November 23,2009 | 03:44 PM
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