Monday, October 28, 2019

Chance to learn more about emerald ash borer

Emerald ash borer is a small, metallic-
green bullet-shaped beetle.
The past week I've been speaking to PMPs at CEU conferences about the emerald ash borer.  Many folks have asked why they've never heard about this pest. I guess that's because it's a relative newcomer to the state and its impact is just beginning to be felt.

If you are one of the many in our industry who has heard little or nothing about this insect, let me enlighten you. The emerald ash borer, Agrilus planipennis (EAB), is a wood boring beetle that attacks trees in the genus Fraxinus, which we know as ash. Since it was first discovered in SE Michigan in 2002 it has spread with alarming speed throughout the midwest.  In 2017 the first beetle was found in east Texas.

The EAB is probably the most devastating forest pest since chestnut blight.  In areas where it has been in place for 10+ years it has virtually wiped out every ash tree. Some fear that certain ash species may be on the edge of extinction thanks to the borer. We have every reason to think the same thing will happen in Texas.

Ash is not as common in Texas compared to Michigan and other parts of the Midwest; but it is an important tree, especially in areas along streams and river bottoms. And it's a very important tree if you have one in your backyard.

Not every one of you provide lawn or tree care services, but if you do you should keep your eye on this beetle.  Even if you don't "do trees" you can still provide a service to your customer by alerting them to the risk of this beetle if they have ash trees on their property.

Emamectin benzoate is an effective
treatment applied by certified applicators.
Currently, EAB has been found in Marion, Cass, and Harrison counties in far east Texas.  Most recently a well-established infestation of the borers has been found in west Tarrant county, just a few miles to the northwest of Fort Worth. Anyone who cares for an ash tree who lives within 15 miles of a known infestation should consider their trees at risk (this includes most homes in Fort Worth), and should consider having it treated.

A handful of insecticides can provide protection of an ash tree at reasonable cost. If you are interested in being on the leading edge of how to treat ash trees for EAB in Texas, there are three workshops coming up, sponsored by the Rainbow Treecare company (Rainbow makes one of the leading insecticides for EAB management). Two of the workshops focus on community EAB management strategies, and one will provide a general introduction to EAB. 

These workshops are webinars.  If you've never attended a webinar, it's a pretty cool, and easy, way to learn. You sit at home or in your office, link up to a website, and watch and listen. You will also have the chance to submit questions and interact with the speakers.  To read about the webinars and register, go to

Other places to learn more about EAB include:

  • The USDA Emerald Ash Borer website is a great source of authoritative information about EAB.   
  • The EAB Information Network is a multinational effort to assemble information about the borer including blogs and general information. 
  • EAB University is part of the EAB Information Network and has recorded webinar sessions on a wide variety of topics from top researchers and arborists in the country. All classes are free.
  • Emerald ash borer found in Tarrant County. Citybugs blog. Story of EAB discovery near Fort Worth.

I hope to write more about this beetle in the future. In the meantime, get out your tree books and read up on ash. Once you learn to distinguish ash you will be able to tell whether a customer's tree is at risk.

Friday, October 25, 2019

Winter has its own pest problems

Paper wasps are common throughout Texas, frequently nesting
in windows and under house eaves. With the advent of cold
weather, many of these wasps will head indoors.
Years ago, a friend described a memorable pest control experience that still makes me chuckle. It was winter, and she had noticed a few wasps flying around her immaculate home. So naturally she called her pest control company. Her technician arrived and noticed a wasp on the fireplace. When he opened the chimney flue to investigate, to his (and her) horror a large ball of paper wasps fell from the flue into his lap. He turned to my friend, fear in his eyes, and yelled, “LADY, GRAB YOUR BABY AND GET OUT OF THE HOUSE!”

I don’t recall how long it took them both to recover their wits and clear out the wasps; but if the PMP had known a little more about paper wasp biology and behavior he could have displayed more finesse and saved his customer an unnecessary fright.

Paper wasps are one of many insects that enter homes and other buildings during the fall and winter. Like paper wasps, many insects protect themselves from cold by instinctively seeking shelter in trees, natural rock formations and (in towns) buildings. This leads to a number of insects that are seen indoors only during the winter months. It’s important to realize what’s going on and how to recognize these often-interesting invaders when they show up in your account.

Polistes wasps 

Take my friend’s wasps. Paper wasps are the most common form of wasp in most Texas towns. The come in different colors and go by different names (e.g., red wasps, hornets, umbrella wasps); but all belong to the same wasp genus, Polistes. During summer months they can be recognized by their umbrella-like, paper nests that hang under eaves of houses, in sheds, and in trees. Polistes wasps do not enclose their nests with a paper envelope like hornets or yellowjackets; but they will sting anyone who gets too close or disturbs their nest. Every fall they exchange their paper nests for locations where they will be protected from ice and winter storms. Preferred sites are high points like chimneys, multifloored office buildings and towers.

Box elder bugs may enter homes in late
summer by the hundreds. 
Unlike summer-active wasps, overwintering paper wasps show little or no aggression. Without a nest to defend, wasps simply lack the instinct to sting. A fly swatter or vacuum are all that is needed to dispatch wasps safely. If my friend’s PMP had calmly put down his lapful of wasps and asked for the vacuum cleaner, no babies need have been evacuated.

Box Elder and Red-Shouldered Bugs 

Box elder and red-shouldered bugs (Boisea trivittata and Jadera haematoloma) are true bugs that feed on seeds of certain trees. They often become pests in later summer and fall when they seek protection from cold weather. To them, buildings must resemble big hollow trees, similar to what they would use for shelter in the woods. Control these insects by sealing doors and making sure window screens are tight and in good repair. Neither insect is damaging to the trees they feed on and they are mainly nuisances when they come indoors. During the summer box elder bugs will be found on box elder and maple trees. Red-shouldered bugs are feeders on soapberry, Chinaberry, golden raintree and other trees in the soapberry family.

Nipplegall Makers 

The hackberry nipplegall maker (Pachypsylla
celtidismamma) is common in homes, especially
where there is a nearby hackberry tree. 
Hackberry nipplegall makers are common wherever hackberry trees grow throughout Texas. These tiny (2 mm-long) insects are small enough to get through most window screens and any small openings in buildings. In the summer these insects form nipple-shaped galls on the leaves of hackberry and sugarberry trees. When they emerge by the thousands from their leafy homes in late summer they are commonly found indoors and especially around windowsills. The good news is that hackberry nipple-gall insects are pretty harmless. They do not bite, do not eat clothes and are a pest only because we don’t like little bugs in our homes.

Multicolored Asian Lady Beetles 

The multicolored Asian lady beetle
(Harmonia axyridis) has become a common
fall indoor pest in Texas homes.
One of the most annoying of the fall invader insects are multicolored Asian lady beetles. These large lady beetles are natives to China and have been causing homeowners headaches since the early 1990s when they first appeared in Texas. In their native Asian home, these lady beetles move into crevices in limestone bluffs in the fall. In the U.S. they are more likely to move into light-colored homes and buildings in wooded areas where the beetles feast on aphids during the summer. Caulking and sealing along roof lines and vacuuming up the (sometimes large) aggregations of beetles where they cluster indoors or in attics is the best solution.

Cricket Hunter Wasps 

The Texas cricket hunter wasp may be
one of the least well-known household
pests in Texas. 
Maybe the least widely recognized fall invader is what I call the Texas cricket hunter wasp. These medium-sized (1/2 inch), black wasps with dark wings can be found year-round but are most common indoors during warm days in the winter and spring. They are commonly seen actively climbing up and down walls of bathrooms and other living areas. So, what are these wasps doing in homes? In nature, female cricket-hunter wasps establish nest sites in holes in the ground, such as rodent burrows, and provision those holes with fresh crickets for their offspring. In urban areas the wasps substitute weep holes and cracks in soil under building foundations for nest sites. Hundreds or possibly thousands of crickets may be stashed under homes or in walls. During periods of warm weather, the wasps’ offspring that have fed on these dead crickets can emerge indoors in large numbers. For more information on these wasps, and how to deal with infestations, check out my online factsheet.

Wintertime may be slower for the pest control business in Texas, but there are still plenty of pests out there. It’s a sign of a true pest control professional to be familiar with the less commonly encountered pests--don’t be caught off-guard when that next winter pest challenge drops in your lap.

Friday, September 20, 2019

Upcoming classes in Dallas and Austin

Just a quick post to let readers know about a couple of pest control classes coming up soon, one in Dallas and one in Austin.

Dr. Bob Davis, BASF, has been teaching ACE Prep Classes
for more than ten years. I guarantee this will be one of the
best training classes you will attend this year.
On September 25 we still have room in our first Bed Bug Academy at the IPM Experience House in Dallas.  The class will cover basic bed bug biology and state of the art information on monitoring and control. The class will be taught by Mr. Alan Brown of ABC Home and Commercial Services in Austin, and myself.  It's an all day class (8:15 am to 5 pm) with CEUs and verifiable training hours for apprentices. Cost is only $60 preregistration. Class size is limited, so don't procrastinate. Registration, agenda, map and more information can be found at

For anyone who has considered becoming an Associate Certified Entomologist, ABC Home and Commercial Services in Austin is hosting an ACE Prep Class on October 1.  I've talked about this class in the past on Insects in the City blog, but if you are unfamiliar, this is a chance to either inspire your study or to do some last minute cramming before the test.  Even if you're not sure whether you want to be an ACE, the class provides an excellent overview of the technical side of being a pest management professional.  Led by Randy McCarty, myself and Dr. Bob Davis, this will be an intense but fun class. Best of all, there is no charge!  To get in there is no fancy registration, simply contact Randy McCarty and let him know you would like to attend (, 512-534-5772). The class will run from 8 am to 4 pm and will be held at ABC Home and Commercial Services office, 9475 East Highway 290, Austin, TX 78724.  Parking on the left side of building.

Remember you can never stop learning. The day you stop learning you might as well hang it up.

Friday, September 13, 2019

Unnecessary trauma: Fire ants in nursing homes

Nursing home patient with with fire ant stings.
(Laquna Ross)
This week Vietnam veteran Joel Marrable died at a Georgia VA Hospital following a vicious attack by fire ants.

According to his daughter, Mr. Marrable was found by staff last week covered with ants. Even worse, family wasn't notified by the hospital after the attack. His daughter learned of the incident only after inquiring about the red bumps on her father's body. Although Mr. Marrable's death has not been directly blamed on fire ants, the incident was traumatizing to all involved.

This story would be more shocking to me, except I have been involved in at least two lawsuits where fire ants attacked patients unable to respond or call for help. And despite the fact that stinging cases are often hushed up, many other incidents occur every year.

It doesn't have to be this way. Fire ants are highly manageable given our scientific understanding of fire ants, and today's pesticide tools. But fire ant management always requires attention to detail. It also requires cooperation and communication between the health care facility and its pest control provider. 

If your company provides pest control for health care facilities, here are some essential elements needed to keep your customer (and you) out of the headlines.

  • Ensure the facility has a policy regarding indoor ants. The plan should include clear staff instructions on how to immediately report signs of ants to your company. 
  • Be sure your staff is always updated on what wings/rooms house high-risk patients.
  • Require patients to be immediately removed from any room with ants to another ant-free location. In this Georgia incident, the patient was returned to his original room only to have fire ants return and attack again a second day. No patient should be returned to an infested room until the indoor and outdoor areas around the room have been inspected, treated and cleared by a pest control professional.  
  • Clean infested rooms with a soap solution and disinfect before allowing any patient to return.  Holes and suspected ant entry points should be either sealed or treated. Cleaning with soap removes traces of trail pheromone that might lure other ants back into the room.
  • Conduct periodic staff training classes to let nurses and other caregivers know how to identify fire ants. In this week's incident it is telling that none of the staff interviewed referred to the ants as fire ants, only "ants."  Fire ants pose perhaps the greatest immediate health threat to aphasic patients, and should not be difficult to recognize with training. 
  • Inspect outdoor areas regularly for fire ants, and train maintenance staff to recognize and report evidence of fire ant nesting around the facility. 
  • Fire ant infestations inside a building can almost always be traced back to a fire ant mound or colony outdoors. It's important to know who is responsible for grounds treatment ahead of time. When one contractor is assigned duty for indoor pest control and another for outdoor pest control, blame-shifting is inevitable. The losers in this game are the patients. Ideally, one contractor should be responsible for both indoor and outdoor fire ant control, so there is no confusion.  
  • Don't rely solely on mound treatments for fire ant control. Broadcast applications of either baits or residual insecticides are always a better option. Fire ant baits are ideal for large turf areas and are typically applied once or twice a year. Residual granular insecticides containing fipronil or bifenthrin can be used annually in landscape areas immediately adjacent to buildings.  The idea is to keep fire ant mounds as far away from the building as possible. Fire ant control should start at the property line, not the final two feet to the building.  
  • Don't allow unlicensed applicators to apply insecticides for fire ants. In Texas, pest control at health care facilities must be performed by a licensed pest control technician or certified applicator. This includes control of ants and other insects, pest birds, plant diseases, rodents, and weeds.
  • Document everything you do in writing on your service report. Document both pesticide and non-pesticide-related actions taken during the visit. Be specific about what pests are found during inspections. Remember, there is no such thing as just an "ant."  Fire ants should be clearly identified. Assume that any of your service tickets could be examined by a lawyer some day. 
If doing pest control around nursing home facilities sounds risky, it is. But a conscientious company can succeed at this business. And a nursing home can be one of the most rewarding accounts you have.  As a friend and colleague points out, the biggest risks happen with "low-bid contractors who are not willing to address underlying problems."  

Mr. Marrable's daughter told the Washington Post that her father "deserved better" than the treatment he received in his last days. Let's make sure all our sensitive accounts, like nursing homes, get the good service they deserve.

For more information about fire ant control in nursing homes, see Extension factsheet ENTO-022.

Friday, August 9, 2019

Where is West Nile virus this year?

If it seems you're hearing less about West Nile virus (WNV) this summer, you may not be imagining it.  Although mosquitoes have been abundant in north Texas this year, for some reason the virus has remained relatively quiet.

Where has WNV gone?

A paper written by epidemiologist Dr. Wendy Chung and colleagues in 2013 may offer some insights on the absence of the virus this summer. Those of us who lived in Dallas in 2012 may remember that summer as the worst human outbreak of WNV ever.  Nearly 400 cases were reported in Dallas County alone, and 19 people died of the disease. The epidemic was so bad that Dallas county resorted to spraying the entire county for mosquitoes by plane--something not seen in north Texas since an encephalitis outbreak in 1966.

Chung and colleagues charted the course of the disease during 2012 and saw high infection rates of mosquitoes early in the summer, followed by a rapid increase in human cases. Looking back over previous years and case numbers, the researchers concluded that an unusually mild winter followed by rainfall patterns ideal for mosquito breeding in the spring (and a very hot summer--West Nile virus multiplies quickly in mosquitoes at higher temperatures) created ideal conditions for an outbreak.

So what's different about 2019? We had a relatively mild winter, with only three days at or below 28° F, and a wet spring--both conditions mosquitoes love. But the summer, at least by Dallas standards, has so far been cool.  Until this week, the DFW Airport weather station saw only two days over 100° F. By the end of July the area usually has experienced more than seven days over 100° F.

These graphs show 2019 mosquito abundance and Vector Index (V.I.) estimates compared to previous years. Although mosquito numbers are high this year, the V.I. has remained low for both Tarrant (=Fort Worth-top) and Dallas counties (bottom). In 2012 the V.I. exceeded the danger level of 0.5 for multiple weeks (blue dotted line). Source: Tarrant County Public Health and Dallas County Health and Human Services.

Predicting WNV

One of the tools used by health departments to predict disease risk for WNV is a statistic called the vector index (V.I.).  The V.I. is calculated weekly from mosquito trap data, and combines information on both average abundance of Culex quinquefasciatus (the main carrier of WNV) and disease incidence in the trapped mosquitoes.  A V.I. of 0.5 or higher for two or more weeks is considered a crisis indicator by some health officials.

The graphs shown here are provided by epidemiologists in Dallas and Fort Worth, and show both mosquito abundance and V.I. estimates for both counties. Despite higher mosquito numbers, the V.I. hasn't ventured above 0.1 for either Dallas or Tarrant counties this summer. Most of the season the V.I. has been closer to zero, hence less need for mosquito spraying and fewer people getting sick. In Dallas county this year there have been no human cases of WNV. Tarrant County (Fort Worth) reports only one case this year with a very low V.I., near zero most weeks (top graph).

According to statistics from the Texas Department of State Health Services, low WNV incidence seems to be true for the whole state this year with no reported human cases as of the end of July.  Harris County (Houston) also reports a light year for WNV, according to the acting director of Mosquito and Vector Control, Chris Fredregill.

Looking Ahead

With this week's string of 100° days in many areas will risk go up?  Certainly West Nile virus remains a threat to all of us through the end of the summer and into the fall; but this late in the season the chance of a major outbreak is probably low. On the other hand, hot weather favors the virus. It's no time to forget about mosquitoes. I expect Aedes mosquitoes (yellow fever mosquito and Asian tiger mosquito) to become more abundant after last weekend's rains.  This week is a good time to get out and dump standing water.  Although Aedes mosquitoes are not major disease risks, they cause most of the itchy mosquito bites we get during the day--and we don't want that.

Why Surveillance Reports?

Integrated pest management is just as relevant for mosquito control as it is for all other forms of pest control.  One of the principles of IPM is to base treatments on pest numbers.  Because mosquito monitoring is expensive and requires special expertise beyond what most PMPs possess, few companies monitor mosquito numbers or disease. However, high quality data may be available from your local health authorities, depending where you live. A pest management company can use this data to alert customers to times of higher disease risk and changes in mosquito abundance.

Every community's mosquito situation will be different.  If you are doing business in a larger metropolitan area, or a mosquito control district, you may have access to the kind of data shown here. To find out, contact your local or regional health department and ask if they provide reports of mosquito abundance and disease prevalence.

In Dallas, weekly reports may be obtained by emailing and requesting to subscribe to the weekly Arbovirus Surveillance Report. For Tarrant County, email and request to receive the Arbovirus Surveillance Report Weekly.  Unfortunately, not all counties have equivalent reporting systems. Harris County provides mapping of areas with virus detection.  And the Texas Department of State Health Services provides weekly reports throughout the summer for the whole state.

An additional source of information for both PMPs and your customers is the Mosquito Safari website. At the Safari you can take a virtual tour of a field and a backyard and learn important facts about mosquitoes. 

If you need more intensive training, our Extension medical entomologist, Dr. Sonja Swiger, is offering classes this year for pesticide applicators wanting to prepare for their Public Health (Category 12) license.  In the fall she also offers several 3-day Master Vector Borne Disease Management Courses around the state.  To learn more, or to register, go to .

Monday, August 5, 2019

Getting to know the Turkestan cockroach

Cockroaches have historically been a top pest and reliable source of business for PMPs.  Indeed, from day one most new technicians are taught to recognize the four most commonly encountered species:
  • the German cockroach--one of our smaller cockroaches, bane of restaurants and homes
  • the American cockroach (a fast and intimidating insect that looks twice as big as it really is when running across a floor or flying)
  • the black, rather nasty Oriental cockroach--pest of sewers and the grounds around buildings
  • the smoky brown cockroach, an outdoor cockroach unafraid to venture into homes. 
Other common species, depending on your part of the country, include the Australian, brown, brown-banded, Asian and field cockroaches.

Figure 1. The adult female S. lateralis (A) and adult female Oriental
cockroach (B) are similar in size and color. Arrow points
to the distinguishing light marking on the forewing margin
of the Turkestan cockroach. Photo modified from Kim and
Rust (2013).
In many parts of the country pest management professionals need to add the invasive Turkestan cockroach (Shelfordella lateralis Walker) to their watch list. This Asian invader is quickly making a name for itself and moving through Texas and other states.

Because the Turkestan cockroach looks similar to other species, you may already have seen it and not realized it was something new. Female Turkestans look like Oriental cockroaches. Male Turkestans look like small American cockroaches or perhaps an innocuous field roach.


The Turkestan cockroach has becoming a significant new pest since it was first reported in Shelford, California in 1978 and El Paso, Texas in 1979.  It has since spread through Arizona and New Mexico, across Texas and even to Georgia.  This week I got my first north Texas specimen, and tentatively identified an emailed photo from Tennessee as a Turkestan cockroach.

Figure 2. To my knowledge, this is the first Turkestan cockroach
recorded from north Texas. Collected from a hotel in Frisco,
TX (VII-29-2019). Note the pale, almost transparent border
at the margin of the forewing, and the size (28 mm/one inch),
which is smaller than a typical American cockroach. Photo
M. Merchant.
If you think this pest won't reach your area soon, think again. Internet commerce is also at work. Turkestan cockroaches are commonly sold online where they are well known in the pet trade as "red runners." They provide food for reptile, amphibian and small mammals. Pet owners like the fact that Turkestan cockroaches breed quickly, do well in captivity and don't climb glass (so are easy to keep in aquaria).

My first North Texas specimen of a Turkestan cockroach came this week courtesy of Emory Matts, with Rentokil Steritech.  Guests at a local hotel recently started complaining of roaches on several floors. Whether this was an invasion from outdoors (males can fly and are attracted to lights at night), or represented an indoor infestation could not be determined.  Though it's often referred to as an "outdoor" insect, the Turkestan is capable of establishing itself indoors, similar to Oriental and American cockroaches.


Figure 3. Turkestan (A) and Oriental cockroach nymphs.
Notice the reddish-brown thorax and dark abdomen of
the Turkestan nymph compared to the uniform brown color
of the Oriental. Photo from Kim and Rust (2013).
According to Kim and Rust (2013), the Turkestan is replacing the Oriental cockroach throughout much of the Southwest as the most important cockroach pest around the outsides of structures.  Common breeding sites are similar to those of Oriental cockroaches, including water meter and irrigation boxes, electrical boxes, hollow block walls, cracks and crevices in concrete, compost piles and potted plants.  However, it appears that in the warm climates of the Southwest, Turkestan cockroaches rush through their 5 nymph stages faster than the Oriental with its 7-10 nymph stages.  A female Turkestan cockroach will produce about 25 oothecae (egg cases) in her lifetime compared to 5-10 oothecae for an Oriental cockroach.  The numbers tell the story as to why Turkestan cockroaches are taking over.

Distinguishing Turkestan cockroaches

The immature Turkestan roach resembles both Oriental and American nymphs in general appearance (Fig. 3).  The Oriental cockroach, however, is uniformly dark-brown and the American cockroach is uniformly reddish brown.  The Turkestan, in contrast, is reddish-brown on the head and  thorax (pro- and meso-thorax) and dark-brown only on the rear of the body.

Figure 4. American (top) and Australian cockroaches. 
Note the bold markings on pronotum and the
forewings of the Australian cockroach, in contrast
with the American, which lacks forewing markings.
Photos, M. Merchant.
Besides size (the male Turkestan cockroach is smaller), American and Australian cockroaches can be distinguished by both the wing borders and markings on the prothorax (shield behind the head)(Fig. 4).  Forewing margins of the Turkestan cockroach are pale and almost transparent compared to the uniform-colored wings of the American, and the bold yellow margins of the Australian. Click here for another image of male and female Turkestans.


Research on control methods for the Turkestan cockroach is still limited; however control methods should be similar as for the Oriental cockroach. Granular cockroach baits can be effective; however, Kim and Rust suggest that higher reproductive and growth rates for the Turkestan cockroach could mean that technicians should need more bait when treating.  Special attention should be paid to pest proofing doors and other building entry points to keep cockroaches outdoors where they pose the least trouble.


Kim, T. and M. Rust. 2013. Life history and biology of the invasive Turkestan cockroach (Dictyoptera: Blattidae). J. Econ. Entomol. 106(6): 2428-2432.

Friday, March 8, 2019

When a bed bug isn't a bed bug

Entomologists get excited over the strangest things. This morning I got my first bat bug sample ever, and I'm still all aflutter.

The pronotal fringe hairs on these common bed bugs
(see arrow) are short, no longer than the width of
the bed bug's eye. This feature is visible with a
hand-lens even through a plastic zip-loc bag, as in
this photo. Image by Mike Merchant.
Bat bugs and swallow bugs are relatives of the common bed bug, Cimex lectularius--the species you are most likely to encounter on a daily basis in the pest control business. There are approximately 100 species in the bed bug family, referred to as cimicids (sigh MISS ids).  Most are specialists on certain types of birds and bats. Generally, these bird and bat feeders have little interest in human blood, and cannot survive without their normal winged hosts.

Most of these other species of cimicid bugs look much like our common bed bug.  They will be flat, oval-shaped and reddish-brown, with adult forms about the size of an apple seed.

Current thinking among biologists is that cimicids that specialize in birds and people are spin-offs from ancestral, bat-loving bed bugs. The data suggest that the switch-over from bat feeding to human feeding may not have been that long ago in evolutionary time. It's not difficult to imagine our ancient ancestors scratching from the first hungry bat bugs checking out other food choices in dark caves.

Today, it's rare to find our common bed bug feeding on bats, though it seems this species is less choosy about hosts than most other cimicids. Cimex lectularius has been found feeding on chickens, pigeons, swallows and even pets (though its clearly preferred host seems to be humans). 

Distinguishing common bed bugs

Though bed bug identification is definitely a job for specialists, fortunately it's not difficult for any PMP to tell the difference between bat bugs and the common bed bug with a hand lens or office microscope.  It has to do with the haircut. 

Common bed bugs, our main human bed bug pest, have a fringe of short hairs on the edges of the pronotum, that "shield-like" plate behind the head (see first picture).  

The pronotal fringe hairs of bat bugs and most
bird bugs (see arrow) are longer than the eye is
wide. Image of an eastern bat bug, Cimex adjunctus,
by Mike Merchant.
Bat and swallow bug fringe hairs are longer (see lower picture). This shouldn't be hard to remember if you think of bats as being hairier than people.  Though this character won't necessarily help you tell a bat bug from a swallow bug or pigeon bug, it is a reliable way to tell one of these non-people feeders from the common bed bug.

Don't walk away

Just because your customer has bat bugs instead of bed bugs, it doesn't mean your job is done. While treating bedrooms with a conventional bed bug treatment is unnecessary (bat bugs do not aggregate around beds, nor reproduce on people), there is still pest control to be done. Bat and bird bugs are best controlled by eliminating their preferred hosts from the structure and possibly treating the roosting/nesting sites for bed bugs.

Host elimination is not as simple as closing entry points for bats or birds. Most birds and all bats are federally protected and cannot be killed, nor active nests destroyed.  Instead, they must be excluded at the end of nesting season.  If you have questions about bird and bat exclusion, it's best to check with your state wildlife department. Nesting season for protected birds and bats varies from one area to another.

Unlike common bed bugs, it's unlikely that bat bugs and the various bird bugs will exhibit high levels of insecticide resistance. Any of the pyrethroid or pyrethroid-combination insecticides for common bed bugs should provide good control of bat and bird bugs around suspected harborages and entry points into living areas.

Bat bug and swallow bugs are not that common in our business. The sample I received today was, I learned later, collected from a home in Indiana.  But if bed bugs are being found in unusual places, especially away from bedrooms, keep in mind that other bed bug species are out there. Remember that pest identification is always the starting point for good pest control. And it can be fun too; ask any entomologist.