# Does the smell of squished cockroach attract other roaches? **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [November 14, 2002, 3:40pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727 "2002-11-14T15:40:11Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![K43](https://avatars.discourse-cdn.com/v4/letter/k/d78d45/32.png) [@K43](https://boards.straightdope.com/u/K43)\ **Post date:** [November 14, 2002, 3:40pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/1 "2002-11-14T15:40:11Z")
There may be no roaches in Norway (though I doubt the claim). However, there are certainly Norway Rats in Norway. They are the common ship rat and have spread throughout the world. When you squish a rat, the smell attracts other rats, too. * * * Link to the Staff Report being discussed,added by CK Dexter Haven as Moderator: [Does the smell of squished cockroach attract other roaches?](http://www.straightdope.com/mailbag/mroachsmell.html) ---
**Author:** ![Barks\_dog\_food](https://avatars.discourse-cdn.com/v4/letter/b/c68b51/32.png) [@Barks\_dog\_food](https://boards.straightdope.com/u/Barks_dog_food)\ **Post date:** [November 14, 2002, 6:53pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/2 "2002-11-14T18:53:28Z")
The only roach in Norway is the kind that lives in the forrest. Roaches come into the country with fruits and other stuff but never survive for long. ---
**Author:** ![chukhung](https://avatars.discourse-cdn.com/v4/letter/c/e79b87/32.png) [@chukhung](https://boards.straightdope.com/u/chukhung)\ **Post date:** [November 14, 2002, 7:09pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/3 "2002-11-14T19:09:29Z")
> [@](#): > > \*Originally posted by Bark’s dog food \* > \*\*The only roach in Norway is the kind that lives in the forrest. Roaches come into the country with fruits and other stuff but never survive for long. \*\* A quick bout with Google puts some doubt to that claim. In this website, [http://www.iacr.bbsrc.ac.uk/enmaria/database/norway/svenma.html](http://www.iacr.bbsrc.ac.uk/enmaria/database/norway/svenma.html), which discusses pesticide resistance in Norway, it states > [@](#): > > The German Cockroach _Blattella germanica_ is probably resistant to several pesticides. From various pest exterminators we have several reports on control failure, while in other cases treatments with pyrethroids seem to work well. This cockroach is the only cockroach important in Norway. This makes it seem like Norwegian exterminators deal with the German cockroach on a fairly regular basis. Regular enough for the vermin to develop resistance to some pesticides, anyway. A more complete description of the German cockroach is at [http://www.cnr.berkeley.edu/citybugs/db/Taxonomy.php3?TaxID=2158](http://www.cnr.berkeley.edu/citybugs/db/Taxonomy.php3?TaxID=2158). It doesn’t look like a forest-dweller to me… ---
**Author:** ![Alan\_Smithee](https://avatars.discourse-cdn.com/v4/letter/a/2acd7d/32.png) [@Alan\_Smithee](https://boards.straightdope.com/u/Alan_Smithee)\ **Post date:** [November 15, 2002, 1:22am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/4 "2002-11-15T01:22:14Z")
Cockroaches live in the forest? This news shouldn’t surprise me, but I keep imagining “Goldilocks and the Three Cockroaches”–“Mama Cockroach, Papa Cockroach, and little Baby Cockroach all lived in a house in the forest. . . .” ---
**Author:** ![flodnak](https://avatars.discourse-cdn.com/v4/letter/f/838e76/32.png) [@flodnak](https://boards.straightdope.com/u/flodnak)\ **Post date:** [November 15, 2002, 8:55am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/5 "2002-11-15T08:55:31Z")
Yes, there are cockroaches in Norway, and the problem, though small, is growing. They come in shipments of foodstuffs. They crawl into suitcases while the owners are baking their brains on warm sandy beaches, and hitch an airplane ride back to the land of the trolls. And I’m sure the little bastards have found a dozen other access routes. ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [November 15, 2002, 12:11pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/6 "2002-11-15T12:11:30Z")
I’m sure with rats it is the same as with cockroaches. Neither has a special chemical that they exude upon death that says to their counterparts, “Hey, there’s a dead cockroach (or rat), come quick!” Rather, both cockroaches and rats are cannibalistic. They smell something dead, anything dead, and that’s the dinner bell. ---
**Author:** ![NutMagnet](https://avatars.discourse-cdn.com/v4/letter/n/ea5d25/32.png) [@NutMagnet](https://boards.straightdope.com/u/NutMagnet)\ **Post date:** [November 15, 2002, 12:25pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/7 "2002-11-15T12:25:23Z")
Alan: Cockroaches live pretty much everywhere. I remember visiting a recently-married couple in Atlanta (Marietta) . They had just bought a house in a new development and invited a bunch of us to a BBQ. We were having drinks when the Mrs. asked her husband to light the grill. He walked over to the screen sliders, picked up a can of bug spray and gave the screens a good shot. Bugs, which I hadn’t noticed till then, fell off the screens by the hundreds. I asked him what all the bugs were, and he replied, “Cockroaches”. I then expressed surprise that there’d be cockroaches in a new development in the suburbs. He told me that they live in the soil, and when the excavation starts, they surface and get all over everything. They’re bothersome for a year or two, then seem to “settle down”. Whodathunkit? ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [November 17, 2002, 12:12am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/8 "2002-11-17T00:12:58Z")
I’ve heard that squishing roaches releases sex pheromones. I don’t know, though. Perhaps someone would be willing to stomp one, then observe if more come (heh) and try to mate with the dead one. I would, but there are no cockroaches in Berkeley. Peace, mangeorge ---
**Author:** ![chukhung](https://avatars.discourse-cdn.com/v4/letter/c/e79b87/32.png) [@chukhung](https://boards.straightdope.com/u/chukhung)\ **Post date:** [November 17, 2002, 12:50am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/9 "2002-11-17T00:50:22Z")
> [@](#): > > \*Originally posted by mangeorge \* > \*\*I would, but there are no cockroaches in Berkeley. \*\* Well, if you can’t find cockroaches roaming wild, perhaps you could contact Prof. Robert J. Full, director of Berkeley’s Poly-Pedal laboratory. There’s a copy of an interesting article about his research into how animals and insects move at (warning: PDF file) [http://www.cim.mcgill.ca/~arlweb/media2/NYTapril042002.pdf](http://www.cim.mcgill.ca/~arlweb/media2/NYTapril042002.pdf). > [@](#): > > During a conversation in his laboratory at the University of California at Berkeley recently, Professor Full pulled a Death’s Head cockroach as long as a cigarette lighter from a Tupperware container and put it on a bug-size treadmill. (I wonder how much energy the world’s cockroaches could produce if we put them all on little treadmills hooked up to electical generators…) ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [November 17, 2002, 1:03am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/10 "2002-11-17T01:03:35Z")
He imported that one from Norway. 🙂 ---
**Author:** ![Fishhead](https://avatars.discourse-cdn.com/v4/letter/f/9f8e36/32.png) [@Fishhead](https://boards.straightdope.com/u/Fishhead)\ **Post date:** [November 17, 2002, 6:33am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/11 "2002-11-17T06:33:45Z")
I passed three wonderful years in Costa Rica in a rainforest area. If I could change one thing it would be the roaches. I can live with the snakes, rats, even the poisonous caterpillars. I just hate roaches. And believe me, there are cockroaches in C.R. Some are bigger than mice. Some are a pretty gold-fleck color, and have a habit of flipping over on their backs and playing dead, then flipping back over and running off when you go get something to sweep them up with. There’s even one kind with miniature preying mantis-like legs, that seems to make its living consuming smaller roaches. I used to encourage the big red, mata-caballo spiders because they eat roaches. But I killed many a roach in that time period, and I can never remember roaches flocking to the carcass or the grease spot that resulted from the smashing. I don’t know if anyone is interested or not, but if desired, I could relate the story of the night in a town called “Africa”, where I slept in a small house that must have the world record for roaches.(excerpt - I took the calendar off the wall and briefly, there was a rectangle of brown that completely obscured the wall in the exact shape of the calendar - then the roaches dispersed looking for undisturbed darkness) ---
**Author:** ![Mr\_Mellow](https://avatars.discourse-cdn.com/v4/letter/m/7c8e57/32.png) [@Mr\_Mellow](https://boards.straightdope.com/u/Mr_Mellow)\ **Post date:** [November 17, 2002, 3:25pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/12 "2002-11-17T15:25:43Z")
The reason for not stepping on cockroaches is they are always pregnent. When you squish the mother roach the eggs will squeeze out and stick to the bottom of your shoe. ---
**Author:** ![Barks\_dog\_food](https://avatars.discourse-cdn.com/v4/letter/b/c68b51/32.png) [@Barks\_dog\_food](https://boards.straightdope.com/u/Barks_dog_food)\ **Post date:** [November 17, 2002, 8:58pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/13 "2002-11-17T20:58:10Z")
I was wrong about roaches in Norway. There are German roaches here, not american, I thought an article said that there were no roaches here but it said no american roaches live here. ---
**Author:** ![Fishhead](https://avatars.discourse-cdn.com/v4/letter/f/9f8e36/32.png) [@Fishhead](https://boards.straightdope.com/u/Fishhead)\ **Post date:** [November 18, 2002, 7:07pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/14 "2002-11-18T19:07:43Z")
We haver German roaches in the USA as well. They are probably the most ubiquitous species of insect in the world, is my WAG. The German cockroach is the main one that we try to get rid of here, but there are other species too, some of them imported. (There’s a new addition in the last few years to Florida that came over from the orient that is expanding like wildfire. I hear that it isn’t really an indoors species, but it is attracted in droves to lights at night, thus can be a real pest. ) I don’t know if there is a species called the American roach, but if there is it isn’t a major pest species. ---
**Author:** ![chukhung](https://avatars.discourse-cdn.com/v4/letter/c/e79b87/32.png) [@chukhung](https://boards.straightdope.com/u/chukhung)\ **Post date:** [November 18, 2002, 8:06pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/15 "2002-11-18T20:06:04Z")
> [@](#): > > \*Originally posted by Fishhead \* > \*\*I don’t know if there is a species called the American roach, but if there is it isn’t a major pest species. \*\* You don’t, I presume, live in Florida? I found the following information about the American cockroach (_Periplaneta americana_) at [http://creatures.ifas.ufl.edu/urban/roaches/american\_cockroach.htm](http://creatures.ifas.ufl.edu/urban/roaches/american_cockroach.htm) > [@](#): > > The American cockroach, _Periplaneta americana_ (Linnaeus), is the largest of the common peridomestic cockroaches measuring on average 4 cm in length. It occurs in buildings throughout Florida especially in commercial buildings. In the northern United States the cockroach is mainly found in steam heat tunnels or large institutional buildings. The American cockroach is second only to the German cockroach in abundance. I also note that “American cockroach” is something of a misnomer: > [@](#): > > The American cockroach (_P. americana_) was introduced to the United States from Africa as early as 1625 (Bell and Adiyodi 1981). By the way, Berkeley’s Poly-Pedal Laboratory (which I referenced in an earlier post in this thread), rates the American cockroach as one of the world’s fastest running insects. Step lively. ---
**Author:** ![dqa](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dqa](https://boards.straightdope.com/u/dqa)\ **Post date:** [November 23, 2002, 5:21am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/16 "2002-11-23T05:21:21Z")
I have to disagree with **Doug** , when he states roaches are only attracted to squashed dead roaches because they are a food source. I refer you to _Use of Fecal Extract Trails to Enhance Trap Catch in German Cockroach (Dictyoptera: Blattellidae) Monitoring Stations_ in the **Journal of Economic Entomology**. [http://www.entsoc.org/pubs/jee/jeetocs/PDF’s/ec030000865p.pdf](http://www.entsoc.org/pubs/jee/jeetocs/PDF's/ec030000865p.pdf) While this may not be the best reference, it is evident that the authors at Virginia Tech believe that aggregation pheremone, which occurs in roach feces, is an important attractant of roaches. > [@](#): > > **The aqueous extract would be particularly beneficial in cluttered environments where cockroach populations are low or moderate. An incipient population in a cluttered environment may never encounter a monitoring station. Applying an extract along edges near the station or even spraying the extract in areas around it would increase the prominence of the station in the environment.** I considered the objection that roach feces are merely another food source, and thus no better an attractant than the discarded McShake. The distinction was not explicit in that article, so i dug around a little more. [Here](http://www.napa.ufl.edu/98news/roaches.htm) is a good article based on an interview with researchers at the University of Florida. > [@](#): > > \*\*“Cockroaches that are not stressed for food will do other things besides look for food,” Koehler said. “They are very curious animals. They like to run around and investigate everything. That’s always been interpreted as a non-response to food, when actually they are exhibiting other behaviors. They investigate, then they feed.”… > > …She developed an extract from roach feces and began testing it at UF’s Urban Entomology Laboratory. First, she found roaches prefer to walk on fecal material rather than a clean surface. So she laid out trails and found roaches will, indeed, follow where other roaches have traveled before. > > “The pheromones are communication devices between cockroaches,” Miller said. “If you have an infestation and have a lot of fecal material around, it advertises, ‘Hey, this is a good cockroach place.’” \*\*[quotation snipped to strengthen my argument] ---
**Author:** ![Donovan](https://avatars.discourse-cdn.com/v4/letter/d/ea666f/32.png) [@Donovan](https://boards.straightdope.com/u/Donovan)\ **Post date:** [November 27, 2002, 2:09am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/17 "2002-11-27T02:09:46Z")
> [@](#): > > I would, but there are no cockroaches in Berkeley. Are you kidding? The first cockroach I ever saw in my life was at Berkley! I was only there for like 4 hours, and I saw one crawl out of a crack in the wall in one of the bathrooms on the UC Berkley campus… ugh, made my skin crawl. Unfortunately, it was not the last one i ever saw… …Was I just wooshed? ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [November 27, 2002, 4:03am UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/18 "2002-11-27T04:03:06Z")
Yeah. ---
**Author:** ![dqa](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dqa](https://boards.straightdope.com/u/dqa)\ **Post date:** [December 7, 2002, 8:29pm UTC](https://boards.straightdope.com/t/does-the-smell-of-squished-cockroach-attract-other-roaches/136727/19 "2002-12-07T20:29:41Z")
I dug a little further on this. Probably should have just done so before that first post, but then that’s why **Doug** gets the big bucks, not me. First, from UNESCO, we have [Study on integrated pest management for libraries and archives](http://www.unesco.org/webworld/ramp/rtf/books/r8820e.rtf). The unclear wording in the third sentence below makes me skeptical about the scholarship behind it, but if nothing else it may be relevant to **bibliophage**. > [@](#): > > \*\*American roaches leave other signs and evidence while feeding on books and paper products. They regurgitate a brown liquid called attar while feeding and resting on materials. > > This attar, which contains chemical pheromones that act as an attractant to other cockroaches, is called an aggregation pheromone. Often smears and tear-shaped droplets of this brown liquid will be left behind (on books and library materials.\*\* For more definitive research on this issue, we must go back to the Journal of Economic Entomology. Evaluation of Attractants for Monitoring Populations of the German Cockroach (Dictyoptera: Blattellidae) by Nalyanya and Schal (2001) at North Carolina State. > [@](#): > > \*\*The aggregation pheromone contains both attractant and arrestant components and cockroaches respond to the attractants by olfaction and to the arrestants by contact chemoreception. Although it is apparent that the Victor pheromone lure is only minimally attractive in olfactometer bioassays, it appears to function as a short-range attractant and arrestant in cage bioassays. Cockroaches clearly preferred shelters that contained the pheromone lure over control shelters. **and** > [@](#): > > Crude fecal extracts containing aggregation pheromones have shown promise in field studies aimed at reducing repellency of contact insecticides, and in laboratory assays of baits\*\* It should be noted, however, that aggregation pheremone performed much more poorly than food baits in most of the tests, and did little to improve the attraction of other baits when paired with them. In fact, **“the most attractive baits that we found were ‘off-the-shelf’ foods (e.g.,peanut butter)”**. In short, **Doug** is substantially correct to say that roaches are attracted to squished roaches simply because they are a food source. However, the answer is incomplete in that aggregation pheremone also seems to play a role, especially when the roaches are sheltering rather than feeding.