Thursday, September 22, 2011

A Pile of 1,202 Stink Bugs

Come and get 'em!

When I saw four Rescue Stink Bug Traps around our neighbors’ home and vegetable garden, I asked if I could count the brown marmorated stink bugs when they cleaned out the traps and replaced the lures.  A recent email from Debbie and Jeff said to come and get four bags of stink bugs, one bag hanging on each trap.  The traps had been in place for four weeks with their original “two-week” lures.

Wow, what great neighbors—they gave me their stink-bug harvest!

I made the rounds of their four traps last Thursday morning and retrieved the sealed plastic bags with mostly dead stink bugs. Each of the bags contained living stink bugs, which indicated to me that the lures were still attracting their quarry long after their advertised two weeks.

I put down the gate of my pickup, laid out old newspapers, slowly maneuvered the living stink bugs into a bottle of soapy water, and with a plastic fork began separating and counting the dead bugs. 

Here’s what I found—plus a few comments:

Four bags of stink bugs to count
Trap One, with solar-powered LED light to attract stink bugs at night, is, like all four traps, located in the lawn.  This one is near the detached garage and about 60 feet from the family vegetable garden.  It contained 332 stink bugs of all sizes (phases or instars), including many first instars about the size of a dog tick.  This number included 10 green stink bugs, another species.

Trap Two, without LED light, contained 378 stink bugs, including one green one, again in all phases. This trap is about 25 feet from the vegetable garden, where most tomatoes show pin pricks from stink bug feeding and where stink bugs still feed on the fruit.  This was the largest count, so did absence of an LED light increase the catch?  I don’t think so.  I suspect the number is evidence of the trap’s proximity to an excellent food supply—garden vegetables.

Trap Three, with LED light, contained 305 stink bugs, including an amazing 68 live ones.  What fun I had getting them out of the plastic bag and into the bottle of soapy water.  Two managed flights to safety, but they are in the count.  I have no idea about why there were so many live bugs in this one trap.

After the count, a pile of 1,202 stink bugs
Trap Four, with LED light, contained only 187 stink bugs.  Why so few?  The message on the bag said it all: “Dropped Catch.”  Oops, accidents do happen, but if we don’t get a National Science Foundation mega-grant, you know why.  When I looked at the collection from this trap, I noticed that all but a few were the larger phases of stink bugs, so I assume that the smaller captives got lost in the grass when they were dropped.  How many were lost?  I decided I’d estimate by averaging the number of bugs in the three other traps, which came to 338.  That suggests that about 151 stink bugs were lost when dropped.

Bottom line: The four traps contained 1,202 stink bugs plus the estimated 151 lost for a total of  about 1,353.

Were Jeff and Debbie impressed by their catch?

Debbie:  “No, I thought after two weeks the traps would be overflowing, but that was not the case.”

Jeff:  “No, but hope springs eternal that we will have fewer of the smelly, fair-weather bugs in the house this winter.  I’ve killed more with pesticide around the flood lights by the garage at night.”

Have the traps reduced the stink bugs in your vegetable garden?

378 stink bugs in nearby trap while these
continued to damage tomatoes
Debbie: “No.  In fact, most of the blooms in our vegetable and flower garden were decimated.  Although the garden was green, every one of the gigantic sunflower heads was thoroughly enjoyed by the bugs.”

Jeff:  “Yes, but the number of bugs in the garden was a few orders of magnitude greater than in the traps.  Stink bugs increased production costs, and although one of the traps was about 25 feet from the garden, the stink bugs preferred the green, leafy vegetation over the green and yellow hard plastic of the traps.” 

Do you think you’ll use them again next year?

Debbie:  "First let’s see how the seven-week refills work.”

Jeff:  “Next year perhaps we’ll set the four traps either under the lilacs or near the back porch light.”

The four traps, with new lures installed on September 13, are now attracting a new collection of brown marmorated stink bugs.


  1. Wow! Looks like a successful stink bug "harvest" to us! When it was time to count the bugs in our Rescue trap experiment, we put the trap in a bag and then in the freezer for a few minutes to slow the live bugs down. That prevented the pests from securing an escape!

  2. I suspect that having live adult stink bugs in the trap provide enough pheromone to keep attracting other BMSBs. My Rescue traps have been up over 6 weeks and are still collecting BMSBs even though the lures haven't been replaced.

    One tactic I'm going to try next year is to use an led light and sticky traps to see if that will reduce the population.