The
easiest way to catch a spider is to place a tube or wide-mouthed bottle
beside it and then gently push in the spider with a stopper. For web-living
spiders, it is important to place the tube below them, as they tend
to drop to the ground when disturbed.
As
glass tubes can break easily in the rough and tumble during field
trips, you should carry plastic tubes or bottles instead. There is
no need to make ventilation holes on the bottle caps as spiders can
survive for a few days in a closed bottle. However, many spiders cannot
withstand heat and will die quickly if the bottles are placed in heat
traps such as a car parked under the sun. As spiders tend to attack
each other, live spiders should be placed singly in each tube. Each
tube should be painted or labelled with a number so that you may subsequently
match the specimens against records of date, locality, habitat and
any observed habits in a notebook. Alternatively, you may insert a
piece of paper with a number written in pencil into the tube. (Do
not use ballpoint pen as the ink will smudge when the paper gets wet.)

Many
elusive or supposedly rare spiders may be collected by sweeping through
vegetation with a sweep net, which is essentially a modified butterfly
net with a tougher white cloth bag and a shorter handle. You may also
hold the sweep net below some branches with one hand and shake the
branches with the other, so that spiders hidden in the foliage will
fall into the net below.
For spiders living among forest litter, the best way to collect them
is to scoop a heap of dead leaves from the forest floor onto a white
plastic sheet spread on the ground, and then remove the leaves piece
by piece to search for spiders. Small spiders in the litter can be
picked up by touching them with a small paint-brush wetted in alcohol.
Small
spiders can also be captured by placing an aspirator above or near
the spider and sucking it up with your mouth (you will not swallow
the spiders unless the gauze is broken!).
The
captured spider can be transferred to a tube by blowing into the aspirator.
Spiders cannot be preserved dry like butterflies and beetles. They
must be kept in 70-80% alcohol (either ethyl alcohol or isopropyl
alcohol), in glass specimen tubes with water-tight stoppers. (For
suppliers of glass tubes and alcohol, look under "Scientific
Apparatus & Instruments" in the Yellow Pages of the telephone
directory.)
Details such as date, locality and habitat should be transferred to
a label written in Indian ink or pencil. Where possible, the name
and the sex of the spider should also be included. The label should
then be placed in the alcohol, together with the spider, inside the
specimen tube. If you wish to immobilise a live spider before transferring
it into a specimen tube, you can do so by freezing it in a refrigerator.
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