ENTOBLITZ
Collecting Techniques:
By William Godwin
Texas
A&M Department of Entomology
Blacklight/mercury vapor light
Seven light sheets were set out in the 27 acre
Godwin Woods each night. That is a record array for the department. We
were probably visible from the space shuttle. This technique has the potential
to produce the greatest quantity of insects by far. However, specimens
collected by light lack the specific microhabitat or host information that
comes from more specific collecting methods. Here we suspend a white sheet
from a clothesline so that the bottom 12 inches or so drape across the
ground. Another white sheet is put on the ground. A mercury vapor light
and ultra-violet light are suspended from the clothesline so that they
hang a few inches away from the sheet. The sheet acts as a big reflector
and as a substrate for the attracted insects to land on.
We gathered around seven different generator powered
UV/mercury vapor lights to collect.
Yellow Pan Traps
Matt Yoder and Matt Buffington put out hundreds of these
little yellow plastic bowls in the woods. They were filled with slightly
soapy water. Insects were attracted to the yellow color and were drowned.
The pans were bought from the paper plate etc. aisle of the grocery store.
If you can't find yellow ones for your picknick then blame a hymenopterist.
They hoard them. This technique is usually directed at Hymenoptera, but
Coleoptera and Diptera are also collected in abundance. It looks like an
easy collecting technique, but putting out 100 pans means you must carry
gallons of soapy water with you. You must also remember where the trap
line is and service them every day with a fine sifter.
Leaf Litter Sifting
Ed Riley demonstrated his technique for collecting leaf
litter insects. Typically collectors just grab a bag full of moist leaf
litter and take it back to the lab to run it through a berlese funnel.
Hard core leaf litter specialists have invented field sifters that allow
them to shake sample after sample over a hardware cloth screen. This allows
them to separate the insects from coarse trash like leaves and sticks.
By concentrating the sample like this they can take the equivalent of many
more times the amount of leaf litter back to the lab.
Malaise Trap
We used a two-headed malaise like this one (because
all the good ones were spoken for). It worked fine though. This trap was
set-up one week before the ENTOBLITZ so that it would have a good sample
in the jars by the time we got there. This trap works on the principle
that some insects fly or crawl up when they encounter a barrier. In this
trap they travel up until they fall into a bottle of alcohol at either
end. We used a mixture of ethanol and propylene glycol (antifreeze) because
the antifreeze inhibits evaporation of the ethanol. This allows us to leave
the trap up for longer periods of time.
Flight Intercept Trap
This trap is designed to collect insects that drop
when they encounter a barrier while flying. It is more suited to Coleoptera
than the malaise trap. Notice the screen with subtending pans to drown
the intersecting insects. A rain lid is provided to keep the pans from
being overflowed in storms.
Pitfall/Dung Trap
This trap method involves a small plastic cup that
is burried up to the rim in the ground so that passing insects may fall
in. Place about one inch of fluid in the cup to trap the insects. You may
use soapy water or alcohol. To increase your catch and target specific
insects you may bait the trap. Use bits of dead meat for carrion beetles.
Use malt or rotten fruit for other samples. We used dung placed in a small
cup near the rim to survey the area's dung beetles. The following are scans
of thescarabs that were attracted to our dung.
Beetles attracted to dung baited pitfalls
Deltochilum
gibbosum (Fabricius)
Canthon
imitator Brown 
Ateuchus
histeroides (Weber)
Geotrupes
splendens (Fabricius)
Phanaeus
difformis LeConte
Omorgus sp. 
Onthophagus
medorensis Brown
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