A mercury vapour light trap

<<<left is a plan of a trap

it is basically a 45 cm square box which is 30cm high and made from 4mm plywood. The 'lid' is formed from two sloping sheets of 2mm Perspex with a gap between them at the bottom. The function of these Perspex sheets is to arrest the flight of the moth, funnelling it down into the trap.

Referring to the plan, two measurements are particularly important. The gap between the bottom of the two sheets of Perspex (marked A) must be 25mm to Allow the moths to enter, but not too many to escape.

The height of the top of the mounting blocks for the Perspex at A should be 15cm from the bottom of the trap. Small pieces of wood (2.5cm square) should be fixed to the centre of the top of the blocks (A) to keep the Perspex sheets 2.5cm apart. The Perspex must be cut (scored with a glasscutter or Stanley knife and then snapped off) to fit the particular trap. Lengthways the sheets must fit snugly between the sides of the trap (approximately 44cm) and the width of the sheets must equal the distance from the mounting block to the top edge of the trap, plus 3cm overhang (about 28cm).

There are 2cm square wooden lengths inside the trap running up each corner and along the bottom of the sides to hold the trap together. These are nailed (and Glued) to the sides and bottom with tacks. Note that the vertical bits do not come quite to the top of the corners to allow for the slope of the Perspex. The plywood bottom of the trap holds the whole thing rigid and 6mm holes should be drilled in each corner to allow rainwater to escape.

Click here for wireing info + diagram.

The lamp mounting board (B) can be made from an odd bit of ply or other wood (7cm wide).

Finally, you should get 3 or 4 square egg trays, usually available free from a corner shop, for the moths to rest under. These are normally about 30cm square and should be cut in half. They stand up, resting on the sides of the trap under the Perspex.

black lighting

Ultra violet black lights Are foot long tubes dangled in front of a white sheet
The moths land on the sheet where you can capture the ones that interest you.
you can also get up to 4ft tubes and a 400!!w lamp.

< (4w 8w) | (20w 40w) | (400w!!) >

4w, 6w, 8w, 20w, 40w, can use a normal fluorescent tube fitting, 400w is like a normal lamp just more powerful

see diagrams for quick start for 4-8W or 20-40W these can run off a car battery.

sugaring and wine ropes.

'sugaring'

is good at attracting certain species not attracted to light. Sugaring involves brewing up a sticky treacly concoction which you paint onto several tree trunks

use a red light (such as the backlight from a bike) to view the moths as they are not sensitive to the red light. Don't restrict yourself to putting the 'sugar' on tree trunks, try flicking drops onto shrubs with broad leaves. Here's the recipe I use

• A bottle of bear

• One or two over-ripe banana

• 2-4 dessert spoons of black molasses or treacle

• 1lb (450g) of the stickiest/darkest sugar you can find

• 1 kiwi fruit

• and a splash of rum

The mixture needs to be heated, mash or liquidise it all together Heat very gently, stiring frequently for 15 to 20 minutes until all the ingredients have dissolved and the mixture is starting to come to boil. Simmer for 10 minutes stirring occasionally, making sure that the mixture does not solidify at the edges or overflow, until it thickens slightly. Allow to cool, again stirring occasionally. Bottle while still lukewarm. Before use stir in a little rum. Apply with a paintbrush. Have plenty of wet-wipes handy to clean up the sticky mess. There are numerous variants on the above recipe, My experience with sugaring is that it can be very variable in results and seems very dependant on the weather - still, humid nights are supposed to be the best. Patches that are regularly sugared are supposed to become more attractive with time.

Wine-ropes

A similar method is to sugaring is to use the method of wine ropeing. Wine ropeing consists of heating up a cheap bottle of red wine in a pan and at the same time dissolving as much sugar as you can into the wine. The mixture is then left to cool and then put in a large container. Make 1 metre long strips of thickish absorbent rope (washing line with the middle removed is good for this) and immerse in the wine syrup and Leave the ropes to soak in the wine syrup.

When required the wine ropes are taken out of the mixture and placed on various bushes and branches of trees and you simply wait for the moths to come to feed. As with sugaring it is useful to use a red light to look at the moths because white lights cause the moths to be disturbed.
Using this method is cheaper than the treacle method but you have to remember where you put all the ropes when you go to collect them at the end of the night.

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