PEST TRAP

Abstract: A pest trap (1, 11) comprising pest retaining means (4, 12) arranged to receive a pest to be trapped and which includes particulate material (6, 17), wherein the fluidity of the particulate material (6, 17) is sufficient to cause a pest so-received to become at least partially immersed therein, thereby retaining the pest in the trap (1, 11). The particulate material (6, 17) may comprise odour absorbing material such as charcoal, silica or calcium chloride and the retaining means (4, 12) may be provided with a pest-dislodging surface (5, 8; 14, 15) to encourage the pest to fall into the retaining means (4, 12) and thereby suffocate in the particulate material (6, 17) which may be highly thixotropic.

Description: PEST TRAP DESCRIPTION This invention relates to a pest trap. Pests, such as houseflies, cockroaches, mice and rats, in urban and agricultural environments are responsible for spreading many disease-causing organisms ranging from Salmonella to bubonic plague. In addition, they have a great nuisance value and must be controlled in urban areas and in agricultural premises, in order to keep such nuisance in check. Pests can be controlled by chemical methods including fumigation of enclosed spaces and use of toxic baits. Trapping is preferable, however, because of the reduced health hazards to Man and because the pests die in the traps and can be disposed of easily. When trapping pests, it is desirable to use traps which contain no toxic ingredients, thus avoiding hazards to the health of users, such as may be caused by contact with or ingestion or inhalation of synthetic pesticides or other poisons. It is also desirable that one trap will catch a number of the pest species concerned. Insects and other animals, for example, rodents, may also be retained by glues in traps, but these have the disadvantage that glue-coated surfaces rapidly become covered with pests, thus limiting severely the trapping capacity of the trap. In the case of rodents, they may remain stuck to "glue boards" for long periods in a highly stressed state, which raises ethical concerns. Alternatively, insects may be killed within the trap by electrocution. Electrocution traps use high electrical voltages, resulting in safety hazards and the need for connection to an electrical mains supply or batteries. Furthermore, the electrocution process disseminates fine particles and insect parts into the environment, which may contaminate food or trigger allergic responses in susceptible individuals. Insects, such as houseflies, may be trapped in funnel-type traps baited with a fermenting protein solution. Such traps are unsuitable near human habitations because of the pungent odours which are released, supplemented by odours of decaying flies in the attractant solution. It is an object of the present invention to provide a pest trap and associated method which overcome, or at least substantially reduce, the disadvantages associated with the known types of pest trap discussed above. Accordingly, a first aspect of the invention resides in a pest trap comprising pest retaining means which is arranged to receive a pest to be trapped and which includes paniculate material, wherein the fluidity of the paniculate material is sufficient to cause a pest so-received to become at least partially immersed therein, thereby retaining the pest in the trap. Preferably, the particle size of the pest-retaining paniculate material is dependent upon the size of the pests to be at least partially immersed therein. For example, a powder or a mixture of powders is preferred. For insects, the preferred particle diameter or size of such a powder is in the range of 1 to 100 microns, whereas, for small rodents, the particle diameter or size of the powder is preferably in the range of 1 to 400 microns. For larger rodents, powder particle diameters or size of greater than 400 microns may be used. Preferably also, the pest-retaining particulate material, such as a powder or mixture of powders, has no chemical toxicity. Further, the depth and particle size of the pest-retaining particulate material are arranged, that is to say, they are sufficiently large and small, respectively, to cause a pest immersed therein to die by suffocation. The particulate material may include or contain a proportion thereof which is an odour absorbing material. Also, the pest-retaining means may be arranged to receive a pest from a smooth surface, a surface having a layer of electrostatically charged or magnetised particles thereon and/or any other form of pest-dislodging surface upon which a pest has attempted to land or otherwise settle. A second aspect of the invention provides a method of trapping a pest, comprising causing a pest to be trapped to be received by a particulate material whose fluidity is sufficient to cause a pest received thereby to become at least partially immersed therein, to retain the so-received pest therein. The particle size of the pest-retaining particulate material may again be dependent upon the size of the pest to be at least partially immersed therein. For example, a powder or mixture of powders may be provided as the particulate material, in which case, the preferred particle diameter or size of such a powder is in the range of 1 to 100 microns for insects and, for small rodents, in the range of 1 to 400 microns. Particle diameters or sizes greater than 400 microns may be used for larger rodents or other animals. Also, the particulate material may be non-toxic and its particle size and depth is preferably arranged, that is to say, they are sufficiently small and large, respectively, to cause a pest to become substantially immersed therein and, as a consequence, to die by suffocation. The particulate material may include or be provided with a proportion thereof which is an odour absorbing material. The inventive method may also comprise a preliminary step of causing a pest to be received by the pest-retaining particulate material, to be dislodged from an associated pest-dislodging surface on which a pest to be trapped attempts to land or otherwise rest. Such a pest-dislodging surface may be a smooth surface, preferably inclined to the horizontal, or a surface having a layer of electrostatically charged or magnetised particles thereon. Thus, in the present invention, pests, such as insects, fall or are dislodged on to and at least partially, but preferably substantially totally, immersed, in a layer of, say, fine powder which presents no chemical toxicity, thus avoiding health and electrical hazards. The powder may be sufficiently fine and fluid that insects sink below the surface as they struggle, thus allowing many more to be retained than would be possible on, say, a sticky surface. The same invention may also be used in modified, so-called "pit-fall" traps to control rodents. In this case, the rodent loses its footing on a slippery surface and falls into a container with a deep layer of fine powder. The powder particles preferably have smooth surfaces to increase their thixotropic properties, i.e. making the powder more fluid and less likely to compact. If desired, this can be increased still further by the addition of water. As it sinks under its own weight, the rodent also rapidly suffocates by inhalation of the powder and/or lack of oxygen. Preferably, the powder used in the invention consists of or contains a proportion of charcoal or other carboniferous material which absorbs odours of the dead bodies of the pests. Examples of other materials which may be used for this purpose include calcium chloride and silica. In order that the invention may be more fully understood, preferred embodiments in accordance with the first aspect thereof and employing methods in accordance with the second aspect thereof, will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a cut-away, elevational view of a first embodiment of pest trap; Figure 2 is a perspective view of part of a second embodiment of pest tray; and Figure 3 is a section along the line LU-III in Figure 2. Referring firstly to Figure 1, an insect trap 1 is made of cardboard and is in the form of an upper box 2 containing two upright cross vanes 3. A base box 4, with downwardly extending flaps 5, has the bottom 2' of the box 1 slotted into it. The surfaces of the vanes 3 and the inner surfaces of the box 1, are coated with electrostatically-charged powder which is known to stick to the feet of insects, so that they are unable to grip those surfaces, as described in International Patent Application No. PCT/GB93/01442 ((Publication No. WO94/00980). The box 4 contains a thick layer of fine charcoal powder 6. An insect, such as a housefly, is attracted into the box 2 by visual and/or chemical attractants (not shown). It is unable to land on the surfaces 8 coated with electrostatically charged powder 7 and after one or more attempts, falls between the flaps 5 on to the surface of the charcoal powder 6. As it struggles to take off, to covers itself with powder, further restricting its ability to fly, and sinks below the surface of the charcoal powder 6 and subsequently dies by exhaustion and/or suffocation. As an alternative to the electrostatically charged particles, the particles may be magnetised so as to stick to the surfaces 8 of the trap 1. The advantages of this inventive trap 1 are that no electrical supply is needed, no toxic chemicals are included, the charcoal powder 6 absorbs the odours of the dead flies and, when full, the trap 1 and contents can be incinerated or otherwise disposed of without adding pollutants to the environment. A second embodiment of inventive rodent trap 11 is shown particularly in Figure 2 in plan view and in Figure 3 in section along the line III-III. The trap 11 has a box 12, preferably of a plastics material, with an outer ramp 13 leading to a plate 14 perforated by one or more funnel-shaped openings 15. The plate 14 forms a perforated top of the box 12 with a further plate 16 forming a roof to the box 12 but allowing sufficient space for a rodent to enter and walk on to the plate 14 from the ramp 13. The box 12 contains a deep layer 17 of fine plastics polymer powder admixed with fine charcoal powder. The funnel-shaped opening 15 in the plate 14 and the surfaces surrounding them are coated with polytetrafluoroethylene to render the surfaces slippery. A rodent entering the trap 11 up the ramp 13, slips on the surface 14 around the entrance to the openings 15 and falls therethrough on to the layer of powder 17. The powder 17 has sufficient fluidity to give way to the weight of the rodent which sinks into the powder 17 as it struggles and dies quickly through suffocation. The desiccating and absorptive action of the charcoal powder reduces the decomposition of the dead rodent and resulting odours, until such time as the trap 11 can be emptied. It will be evident to those skilled in the art that the dimensions and overall design of the inventive traps can be adapted to the size and behaviour of the pests concerned It will also be evident that the retaining powder or other medium can be selected from a variety of materials which can be inert on topical application or by ingestion and have particle size, mass and surface characteristics which prevent agglomeration under pressure. Thus, by appropriate selection of materials and incorporation of suitable attractants, traps can be fabricated which will immobilise, or immobilise and suffocate, pests, such as dipteran flies (Diptera), including houseflies, blowflies, stable flies, warble flies, cluster flies, fruit flies, mosquitoes and tsetse flies, wasps, ants, moths, blood-sucking bugs, insect stored product pests, wood-boring beetles, cockroaches, mice and rats. Examples of powders which can be used include waxes, plastics polymers, powders containing metal salts, ceramics, cellulose and chitin-containing powders.

Claims: CLAIMS 1. A pest trap (1, 11) comprising pest retaining means (4, 12) arranged to receive a pest to be trapped and which includes particulate material (6, 17), wherein the fluidity of the particulate material (6, 17) is sufficient to cause a pest so- received to become at least partially immersed therein, thereby retaining the pest in the trap (1, 11). 2. A trap according to claim 1, wherein the particle size of the pest-retaining particulate material (6, 17) is dependent upon the size of the pests to be at least partially immersed therein. 3. A trap according to claim 2, wherein the particulate material (6, 17) is a powder or a mixture of powders. 4. A trap according to claim 3, wherein the particle diameter or size of the powder (6, 17) is in the range of 1 to 400 microns. 5. A trap according to claim 4, wherein the particle diameter or size of the powder (6, 17) is in the range of 1 to 100 microns. 6. A trap according to claim 3, wherein the particle diameters or size of the powder (6, 17) is greater than 400 microns. 7. A trap according to any preceding claim, wherein the particulate material (6, 17) has no chemical toxicity. 8. A trap according to any preceding claim, wherein the depth and particle size of the pest-retaining particulate material (6, 17) are arranged to cause a pest immersed therein to die by suffocation. 9. A trap according to claim 8, wherein the particulate material (6, 17) is highly thixotropic. 10. A trap according to any preceding claim, wherein the particulate material (6, 17) comprises an odour absorbing material. 11. A trap according to claim 10, wherein the odour absorbing material comprises charcoal, silica or calcium chloride. 12. A trap according to any preceding claim, wherein the pest-retaining means (4, 12) is arranged to receive a pest from a pest-dislodging surface (5, 8; 14, 15) upon which a pest has attempted to land or otherwise settle. 13. A trap according to claim 12, wherein the surface (5, 8; 14, 15) is smooth. 14. A trap according to claim 12, wherein the surface (5, 8; 14, 15) comprises a layer of electrostatically charged or magnetised particles thereon. 15. A method of trapping a pest, comprising causing a pest to be trapped to be received by a particulate material (6, 17) whose fluidity is sufficient to cause a pest received thereby to become at least partially immersed therein, to retain the so-received pest therein. 16. A method according to claim 15, wherein the particle size of the pest-retaining particulate material (6, 17) is dependent upon the size of the pest to be at least partially immersed therein. 17. A method according to claim 16, wherein the particulate material (6. 17) is a powder or mixture of powders. 18 A method according to claim 17, wherein the particle diameter or size of the powder (6, 17) is in the range of 1 to 400 microns. 19. A method according to claim 17 or 18, wherein the particle diameter or size of the powder (6, 17) is in the range of 1 to 100 microns. 20. A method according to claim 17, wherein the particle diameter or size of the powder (6, 17) is greater than 400 microns. 21. A method according to any of claims 15 to 20, wherein the particulate material (6, 17) is non-toxic. 22. A method according to any of claims 15 to 21, wherein the particle size and depth of the particulate material (6, 17) is arranged to cause a pest to become substantially immersed therein and, as a consequence, to die by suffocation. 23. A method according to any of claims 15 to 22, wherein the particulate material (6, 17) is highly thixotropic. 24. A method according to any of claims 15 to 23, wherein the particulate material (6, 17) comprises an odour absorbing material. 25. A method according to claim 24, wherein the odour absorbing material comprises charcoal, silica, or calcium chloride. 26. A method according to any of claims 15 to 24, wherein the pest, to be received by the pest-retaining particulate material (6, 17), is firstly dislodged from an associated pest-dislodging surface (5, 8; 14, 15) on which a pest to be trapped attempts to land or otherwise rest. 27. A method according to claim 26, wherein the surface (5, 8; 14, 15) is smooth . 28. A method according to claim 26 or 27, wherein the surface (5, 8; 14, 15) is inclined to the horizontal. 29. A method according to claim 26, wherein the surface (5, 8; 14, 15) has a layer of electrostatically charged or magnetised particles thereon.

Inventors: HOWSE PHILIP EDWIN, HOWSE, PHILIP, EDWIN
Applicants: HOWSE PHILIP EDWIN, UNIV SOUTHAMPTON, HOWSE, PHILIP, EDWIN, UNIVERSITY OF SOUTHAMPTON
Application year: 1999
Main classification: A01M1
IPC codes: A01M1, A01M23