MONITORING TRAPS

There are many different roach traps on the market, but they differ greatly in their effectiveness. The single most important feature of a roach trap is the attractant, since this determines whether there are nymphs, gravid females as well as adult males present.

A large number of traps found on the North American market are baited with fish oil or palm oil incorporated into the glue, however one trap that was developed in the UK by Agrisense-BCS contained a combined food attractant/pheromone mimic bait - the GP2 lure. Independent comparison trials of a selection of North American traps showed that the attractancy of the trap with the GP2 lure was far superior to all the others - it is for this reason that we use it in our traps.

In the mid 1990's, Cooper Mill began to re-design the traditional Lo-Line Roach trap in an attempt to make it more attractive to the insect, including having it darker inside, and lower in profile to resemble the kind of protective environment that the roach would normally seek out. For economic reasons, the trap contained a removable sticky insert, so that it could be serviced more readily and also re-used. The outside of the trap was printed with a plain dark colour devoid of any lettering, so that it would be less obtrusive in a residential setting. The dark internal surface also helped to reduce the drying out of the glue caused by UV light, and the trap shell was recyclable. This trap was named the '2000 Trap'.

TRAP PLACEMENT

In order to find the sources of infestation, it is important to check all areas where sightings have been reported or droppings are found. Particular attention should be paid to any area where food is stored, processed, cooked or served, and where there may be a source of water, either from leakage or condensation on pipes. This means that the primary target areas will be kitchens and bathrooms. However, don't be fooled into thinking that these are the only areas where roaches may be found. Books are often targeted by roaches on account of their glue bindings, and clothes storage cupboards aren't immune either, so keep an open mind and check everywhere that a roach may gain access. If you are dealing with a new location and are uncertain about the insect harbourage areas, distribute a large number of the more economical Detector traps with the GP2 lure, throughout the building. Check these traps frequently and a pattern of insect distribution will emerge to guide you toward areas of highest insect population. Once these areas have been identified, make a plan, prepare a number of the '2000 Traps', and mark them on the underside with the location and date.

'2000' TRAP SETUP

In order to find the sources of infestation, it is important to check all areas where sightings have been reported or droppings are found. Particular attention should be paid to any area where food is stored, processed, cooked or served, and where there may be a source of water, either from leakage or condensation on pipes. This means that the primary target areas will be kitchens and bathrooms. However, don't be fooled into thinking that these are the only areas where roaches may be found. Books are often targeted by roaches on account of their glue bindings, and clothes storage cupboards aren't immune either, so keep an open mind and check everywhere that a roach may gain access. If you are dealing with a new location and are uncertain about the insect harbourage areas, distribute a large number of the more economical Detector traps with the GP2 lure, throughout the building. Check these traps frequently and a pattern of insect distribution will emerge to guide you toward areas of highest insect population. Once these areas have been identified, make a plan, prepare a number of the '2000 Traps', and mark them on the underside with the location and date.

• fold along the pre-marked lines shown on the assembly diagram
• make sure that the ends of the trap form the necessary 'lip' that the roach has to climb over in order to get into the trap - this lip is important since it unbalances the roach as it drops down onto the glued insert and makes escape by 'backing up' more difficult for the roach
• remove the GP2 lure from the sealed pouch and place it in the centre of the glued insert, then slide the insert into the trap

There is no absolute number of traps that must be placed - a guideline is 2 traps in 10 sq. metres, but this can vary with the severity of the infestation. The lure will be effective for 6 weeks or more under most conditions, but in areas of high moisture, the lure will decompose faster and need replacing more often. If kept in cool conditions, the GP2 tablet will keep for 3 years in its pouch.

Gaining information is the purpose of monitoring, so traps must be checked on a regular basis and the catches recorded. The traps should be left in the same position after checking. If the sticky insert is largely covered with trapped roaches, replace the insert and lure. There is no need to remove the trap if only a few roaches are caught on it, since these trapped roaches often release an aggregation pheromone that will attract more roaches to the trap.

Roaches only spend about 17% of their time feeding, and in the case of gravid females, even less, so keep the traps in place and delay making any decision on chemical treatment until you have a good picture of where it is necessary. Try and place the traps in darker, shaded areas, since roaches often avoid brightly lit areas.

Many chemical treatments, especially synthetic pyrethroids, are repellent to roaches, and may cause some to move to other areas and escape the treatment, so after having treated an area, put out new traps to confirm the success of the treatment and to avoid surprise areas of re-infestation.

STORAGE AND HANDLING OF TRAPS

It is important to store monitoring traps and attractants where they will not be cross contaminated by chemicals or damaged by heat. This means that care should be taken not to leave them in a parked vehicle during a hot day, also when handling other chemicals, be careful not to handle the lures more than necessary, since unwashed hands may in turn contaminate the lures and cause them to be repellent.

SUMMARY

When monitoring any insects, it is very important to understand both the life cycle and behaviour of those insects. For example, the '2000 Trap' will attract and catch the tiny semi-transparent nymphs as well as adults, and in colder regions these cockroach nymphs can take 3 months or more to develop into adults which can re-emerge a long time after any treatment. The on-going use of traps is important since it will help to capture many of the remaining roaches, and will give a good early warning system of any new infestation. You can't beat an inspection system that works 24 hours a day and 7 days a week.

TRAP PLACEMENT

The purpose of the Dome Trap is to monitor a situation where fruitflies can occur. In most instances the increased catch will indicate inadequate sanitation, and the remedy might well be simple. In other cases, it may be discovered that drains and spillage areas require treatment to knock down the population and the appropriate chemical treatment can be applied if the infestation continues after improved sanitation. In the meantime the continued use of traps will monitor any worsening or improvement of the situation.

Traps should be hung in areas of potential food spillage. The hanging height of the trap is not critical but should be placed where they can easily be inspected and do not impede operational activities.

The Dome Trap, the Omni Trap and the Mini Trap are all effective traps for fruitflies when used with the specially-formulated liquid bait, and are particularly useful in bars and taverns where drink spillage is common, as well as many other locations such as vegetable & fruit produce areas, kitchens, wineries, breweries and composting areas. Each trap can be re-used for many years and does not present any hazard to consumers or those working in the treated areas.

The Dome Trap is designed purely as a hanging trap, whereas the Omni Taps can be used either as a hanging trap or a standing trap (the small feet moulded into the trap will lift it high enough to allow insects to enter beneath). The Mini Trap is generally used on shelves or underneath counters and can be opened or closed as required.

HANDLING AND PLACEMENT OF THE LURES

Each 'Long-Life Fly Attractant Tablet' is packaged in a foil pouch to ensure freshness, and should be kept in a cool place until ready for use. The lure is made in the form of a hard tablet, with a red pheromone-impregnated pad attached to one side.

The tablet can be attached to either the inside or to the outside of the light trap, or even placed nearby. Make sure that the red pheromone pad faces upwards, so that the pheromone can diffuse out freely into the air. More than one tablet per light trap may be used. Dampen the tablet prior to putting it in place, since the tablet requires a certain level of humidity in order to ensure immediate release of the attractant - this is especially important where humidity levels are low.

Once the tablet has been taken out of the foil pouch, it will be effective for approximately 3 months, after which time is should be replaced with a new tablet.

STEP 1. THE INITIAL INVESTIGATION

The initial detective work is one of the most important stages of setting up a monitoring program.

A. Determine that the insect problem is in fact Indian Meal Moth. There are a number of different warehouse moths, so familiarize yourself with the main characteristics of IMM and understand its life cycle and typical behaviour.
B. Search the area carefully and try and find out where the problems are.

• Survey the entire area, both inside and outside the building and make a detailed diagram that shows the access points and where the different foods or food ingredients are stored.
• Look for damaged packaging, spillage and for poor sanitation areas.
• Check that doors into the storage and manufacturing areas fit tightly and that ventilation ducts are all properly screened to prevent insects entering from outside.
• Inspect pallet storage areas and garbage disposal bins and check what adjacent industries surround the plant location, since these might be a source of infestation.
• Ask managers where raw material products are received from and where they are placed within the plant once they are received.
• Also verify the condition of incoming trucks and pallets and check whether empty pallets are stored inside the plant.
• Find out how long products remain in storage, and ask about seldom used ingredients, such as spices, which could have been open for many weeks. Product samples are often kept for years, so check storage rooms carefully.
• Familiarize yourself with the entire production process of the plant and the storage routines.

STEP 2. SETTING UP THE TRAPPING PROGRAM

Being well organized from the outset will save hours of frustration and wasted time later on.

A. Measure the location and make a map.
B. Look for suitable hanging or placement sites for the traps and draw them on your site plan.
C. Assemble and number the traps, place the pheromone lure on each of them and record the location and date on your map/chart.
D. Position the traps where they are easily accessible.

The rate of application will depend on the individual location, but as a guideline, start off with traps positioned about 10 metres apart throughout the storage/production areas, at a height that allows for easy inspection. Prepare an inspection record chart on which to record the catch each visit and if required, leave a copy with the plant manager, so you can discuss the situation on each visit.During the warmer periods of the year, make sure that several traps are placed outside the building, near loading bays or other entranceways.

STEP 3. MONITORING AND UNDERSTANDING THE RESULTS

Your objective is to make a sweep of the entire premises in order to establish likely areas of infestation, and then gradually concentrate more traps in high catch areas. The most important part of monitoring is to maintain a regular interval trap inspection procedure otherwise the information collected will be of little use when you try to diagnose the trends. The frequency of your inspection will depend on many things, but you should aim for a maximum of 7 days between visits initially, making sure that the period between visits always remains the same.

Every trap should be checked on a visit, and the insect catch counted and recorded for each trap. After counting the catch - SCRAPE OUT the caught moths, so that you start each new period with an empty trap. Pheromone lures will need to be replaced after 4-6 weeks - change all the lures on the same visit.

After about 4 -6 visits you will start establishing some data showing where catches are most frequent. Move more traps into those areas to verify the situation and start looking for signs of spillage, broken packaging or any item that has been stored in the area for a longer than usual time. If you can't locate a problem area, but nevertheless suspect one, place additional traps in corners or blind alleyways between pallets where there are fewer air currents. This may help to locate the problem. Discuss your findings with the plant manager, and establish what new product movements may have occurred in that area of the plant that could have created the problem.

HANDLING AND ASSEMBLY OF TRAPS AND LURES

The best choice of trap for stored product pests is the Delta II style trap (Pink Trap) with end flaps that fold inwards to make a small triangular opening at each end. The Diamond Trap is quicker to assemble initially, but is smaller and can be more prone to dust contamination, which affects the stickiness of the glue. For very dusty inside areas or outdoors, the Funnel Trap is another good trap choice, and if those areas are well lit, the Black Stripe Trap will perform even better because it also incorporates a strong visual attraction.

Pheromone lures should be kept sealed until ready for use, preferably in a refrigerator or in a freezer for long storage periods. The lures can be damaged under extremely hot conditions. Do not handle lures unnecessarily after they have been taken out of their foil pouches - simply drop them onto the sticky floor of the trap. Replace the lures every 4-6 weeks, and remove the old lure from the trap.

The manner in which a pheromone is detected by an insect is a very precise process and it is therefore important that improper handling or storage does not cause the monitoring traps and pheromones to become contaminated. Many pesticides are repellent to insects and therefore monitoring traps should not be stored in areas where they might be contaminated by vapour transference. Working vehicles are often contaminated with chemicals, so it is wise to keep traps and lures in the cab, or in a sealed box, where they are not subjected to any repellent chemical fumes.

Once a regular monitoring program has been established, it is wise to look at the channels of distribution and transportation of all raw materials and end products in and out of the plant. Cross-contamination can easily occur if products are in contact with infested products while in transit. The longer you maintain a monitoring program, the lower the population of moths will usually become, and in many situations, continuous monitoring will eliminate the need for additional treatment. There is always a risk of accidentally bringing in new infestations, especially if sanitation and structural plant maintenance are neglected, so stay on top of IMM problems by keeping a continuous monitoring program in place.