Abstract:
This invention relates to traps for flying insects, and in particular, relates to a self-supporting and re-usable trap for wasps, yellowjackets and flies. A trap for insects comprising a bag having a first generally flat collapsed configuration for storage and a second expanded configuration for operation thereby forming an internal chamber for trapping insects. The bag includes a first side wall and a second opposite the side wall and at least one entry portal for insects, said first circular entry portal penetrating said first side wall and communicating with the chamber. The trap can include a suitable attractant for attracting insects to the entry portal.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a novel design of a trap for flying insects. In particular, the invention relates to a hangable or self-supporting and re-usable trap for wasps, yellowjackets and flies. 
       BACKGROUND 
       [0002]    Wasps are classified in the group Vespoidea. The wasps most frequently encountered by humans belong to the genera  Vespula, Dolichovespula , and  Vespa  (yellowjackets and hornets). These pests are of medium size (10-25 mm), and are readily distinguished by the bands of black and yellow or white on their abdomens. The most aggressive species encountered is the German yellowjacket,  Vespula germanica.  These wasps have a habit of scavenging in city garbage cans. Wasps are capable of repeatedly stinging their victim as well as inflicting painful bites. Yellowjackets are a common sight in urban and rural areas throughout North America and are the most common stinging menace in many North American cities. In some cases, severe allergic reactions to the wasp venom have resulted in death. 
         [0003]    Flies in many families, e.g. Muscidae, Calliphoridae, Anthomyiidae, constitute a nuisance whenever they are encountered by humans. They are also capable of transmitting a variety of diseases, and are recognized as a threat to public health. While the presence of flies in a person&#39;s dwelling is unwelcome, they are even less welcome in restaurants. The presence of flies is potentially dangerous in hospitals. Many chemical insecticides are used to control flies, and numerous traps of various designs are used to remove flies from man-made structures, and their environs. 
         [0004]    A number of devices have been disclosed for trapping wasps and flies. One such device is disclosed in U.S. Pat. No. 4,551,941 by Schneidmiller. This device relies on a volatile olfactory attractant. Another device is exemplified in U.S. Pat. No. 6,637,149 by Bauer. This device appears to comprise a number of discrete parts and as a consequence would be expensive to manufacture and therefore costly to ordinary consumers. 
         [0005]    US Patent Application 2005/0005503, Bragg, discloses a hanging fly trap in the form of an artificial plant basket. This device must be hung out of sight and so some effort is required to monitor the number of flies caught by the trap and then retrieve the trap for cleaning and replacement of adhesive surfaces. 
         [0006]    There is a growing need for effective, safe and inexpensive traps for wasps and flies around human habitation. 
       SUMMARY OF THE INVENTION 
       [0007]    The invention is directed to a trap for insects comprising: a bag having a first generally flat collapsed configuration for storage and a second expanded configuration for operation thereby forming an internal chamber for trapping insects, said bag comprising a first side wall and a second opposite side wall; an entry portal for insects, said entry portal penetrating said first side wall and communicating with said internal chamber; and a suitable attractant in the bag for attracting insects to the entry portal. 
         [0008]    The trap can include a second opposite entry portal for insects, the second circular entry portal penetrating the second side wall and communicating with the internal chamber. 
         [0009]    The bag can be formed of a resilient plastic. The plastic can include a bonded barrier material. The one or more side walls can be transparent. The interior of the chamber can contain a fluid. 
         [0010]    The bag can have a sealable top end. The bag can have a bottom surface comprising an oval-shaped bottom member having a longitudinal axis. 
         [0011]    The longitudinal axis can comprise a fold line so that when the bag is in a generally flat configuration the oval-shaped bottom member folds symmetrically along the fold line and when the bag is in the expanded operating configuration the oval-shaped bottom member unfolds to form a self-supporting base. 
         [0012]    The first and second transparent side walls can include a translucent, low reflective, rectangular or variously shaped appropriate portion having a colour suitable for attracting insects. The first portal and the second portal can be offset laterally from each other. 
         [0013]    The fluid can be a predetermined volume of water for drowning insects, the predetermined volume of water stabilizing the trap when placed on a level surface. The water can contain an attractive chemical lure. An insect attractant can be located within the interior of the trap above the two portals. 
         [0014]    The top region of the trap can include a releasable pressure sealing strip. The top region of the trap can include an eyelet which enables the trap to be suspended from an object. 
     
    
     
       DRAWINGS 
         [0015]    Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive. 
           [0016]      FIG. 1  is a schematic elevation view of a side wall of one embodiment of the invention. 
           [0017]      FIG. 2  is a schematic elevation view of the opposite side wall of the same embodiment as  FIG. 1 . 
           [0018]      FIG. 3  is a schematic end view of one embodiment of the invention in a flattened configuration. 
           [0019]      FIG. 4  is a schematic end view of one embodiment of the invention in an expanded configuration. 
           [0020]      FIG. 5  is a bottom view of one embodiment of the invention. 
       
    
    
     DESCRIPTION 
       [0021]    Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense. 
         [0022]    Referring to  FIGS. 1 to 5 , there are shown five views of one embodiment of the invention which is a re-usable bag trap  10  for wasps and flies. The trap  10  can be either self-supporting or suspended by an eyelet with a tether. The invention comprises a bag  12  of suitable material, preferably of resilient plastic, with or without a bonded barrier material. 
         [0023]    As seen in  FIG. 1 , the bag  12  comprises a first side wall  16  which in a preferred embodiment is transparent. (There is also a second opposite transparent side wall  18  which is visible in  FIG. 2 .) A first circular entry portal for wasps  20  penetrates the first transparent side wall  16  so that the portal  20  is in communication with the interior of the wedge-shaped chamber  14  (see  FIG. 4 ). The portal  20  comprises a sloped portion  21  and an outside flat surface  23  which forms a flange for adhesive attachment to the side wall  16 . The outer surfaces of both are roughened to facilitate traction by insects landing on and entering the trap. 
         [0024]      FIG. 2  illustrates a second opposite circular entry portal  22  for wasps which penetrates the second transparent side wall  18  and communicates with the interior of the wedge-shaped chamber  14  (see  FIG. 4 ). The second portal  22  is fastened adhesively to the side wall  18 . To the interior of the entry portals  20  and  22  there are frusta-conical passageways  27  and  29  (see  FIG. 4 ). These passageways  27 ,  29  are designed to foil attempts by the insects to leave the trap, in part by having a smooth surface facing the interior of the chamber so that traction by captured insects is impeded. In this way, insects can enter the interior chamber  14  from either sides of the trap through the respective portals  20  or  22  but find it difficult to leave. 
         [0025]    As seen in  FIGS. 1 and 2 , the first and second transparent side walls  16 ,  18  respectively include translucent rectangular portions  40  and  42  which are of a colour suitable for attracting wasps. In one embodiment of the invention this colour is yellow, which is known to be a preferred wasp attractant colour. Other colours effective in attracting such pests can also be used. In another embodiment of the invention, the coloured surface may be in a matte finish, so as to reduce reflection which may deter attracted insects. The rectangular portions  40 ,  42  span each entry portal. In other embodiments of the invention, the portions  40 ,  42  can be modified into different shapes, e.g. ovals, circles, trapezoids or irregular shapes. 
         [0026]      FIGS. 1 and 2  demonstrate that the first portal  20  and the second portal  22  are offset horizontally along dotted line  25 , which appears for reference. Offsetting portals  20  and  22  permit the bag  12  to fold reasonably flat for storage and packaging because the portals  20 ,  22  do not collide with one another. Once the bag  12  is expanded to its operating position, as show in  FIG. 4 , the portals  20 ,  22  are on opposite side walls from each other, with the conical passageways  27 ,  29  extending inwardly. Since the portals  20  and  22  are offset along the horizontal, they do not connect and thus discourage the insects from flying into the first portal  20  and out the opposite portal  22 . 
         [0027]    The bag  12 , as seen in  FIGS. 1 and 2 , has a sealable top end  26  comprising a releasable sealing strip  28  which can be opened as required for cleaning the trap and then resealed. In this way, the trap  10  is reusable and prevents unnecessary waste. The bag  12  has a sealed bottom end  30  comprising a bottom surface  32  in turn comprising an oval-shaped bottom member  34  having a longitudinal fold line  36  (see  FIG. 5 ). 
         [0028]    The trap  10  can have a first generally flat configuration for storage as shown in  FIG. 3  and a second expanded operating configuration as shown in  FIG. 4 . In the second expanded operating configuration shown in  FIG. 4 , there is formed a wedge-shaped internal chamber  14  for trapping and containing insects. The trap  10  can be suspended from a tether or hook using reinforced eyelet  46 , if preferred. 
         [0029]    Referring specifically to  FIG. 3 , which illustrates an end view the bag  12  in a flat configuration for storage, the fold line  36  acts to enable the oval-shaped bottom member  34  to fold symmetrically so that it rests in a folded configuration within the bottom region of the side walls  16  and  18 . Bait attractant such as 1-heptylbutyrate, available from Contech Enterprises Inc., can be suspended inside the bag  12  above the portals  20 ,  22  and is shown as  24 . 
         [0030]    Referring specifically to  FIG. 4 , when the bag  12  is in the expanded operating configuration, the oval-shaped bottom member  34  unfolds to form a bottom surface  32 . When in its expanded configuration as shown in  FIG. 4 , the sidewalls  16  and  18 , with bottom surface  32 , enable the trap to be self-supporting on flat surfaces  38  such as picnic tables. 
         [0031]    Continuing to refer to  FIG. 4 , the bag  12  is adapted to contain a predetermined volume of fluid  44  (usually water) for drowning insects. To attract insects to the trap  10 , a water soluble chemical lure or emulsifiable concentrate can be added to the water. Alternatively, an attractive chemical lure can be floated on the surface of the fluid within the trap  10 . The weight of the water acting on the bottom surface  32  acts to expand the bag, keeping the walls  16 ,  18  and entry portals  20 ,  22  apart, and allowing the inner chamber  14  to expand to its full wedge-like volume. The water also acts to stabilize the base of the bag  10  so that it does not easily tip over when set on a flat surface. The water preferably fills the bag  12  up to a suitable level as indicated by dotted line  48 . 
         [0032]      FIG. 5  depicts a bottom view of the sealed bottom end  30  of the trap in its expanded form. The longitudinal fold line  36  is shown as well as first sidewall  16  and second sidewall  18 . 
       Example 1 
     Test of Bag Traps for Yellowjackets 
       [0033]    Prototype bag traps were manufactured from commercially-available plastic bags (19×30 cm). The bags tapered to a zip-lock top and the bottom expanded when liquid was added (approximately 425 mL per bag. 
         [0034]    The bags were fitted with small or large entry ports made from funnels used to deliver food pastes (e.g. mustard) from squeezed plastic containers. The inward-directed funnels were on opposite sides of the bags, and were offset laterally, so that the bags laid quite flat when not in use. They were placed vertically at mid-level of 10×16 cm bogus labels on each side of the bags made by painting the area with yellow paint (Painter&#39;s Touch Sun Yellow gloss latex, RUST-OLEUM Corp, Toronto, Ontario). The bogus labels were located 7 cm from the bottom of the traps. It is known that yellowjackets are attracted to “buttercup yellow”, which Sun Yellow paint mimics. 
         [0035]    Experiments were set up as randomized, complete blocks, with 12 replicates. Between trap distance was ≧5 m. Experiments were run in commercial orchards east of Kelowna, BC, Canada. All traps were baited with one heptyl butyrate flexlure (Contech Enterprises Inc., Delta, BC, Canada) taped to the inside of the trap. The fluid in the bottom of the trap was 50% apple juice with a dash of laundry detergent added to ensure capture of wasps. Captured yellowjackets were identified to species in the field using a pictorial key (Akre, R. D. et al. 1980, Yellowjackets of America north of Mexico, USDA Agriculture Handbook No. 552, p. 23). Means were analyzed by ANOVA followed by the Tukey-Kramer LSD test. In all cases, α=0.05. 
         [0036]    Experiment 1 was run at the Brar Orchard from 8-10 Jul. Sufficient numbers of yellowjackets were captured (1-2 per trap) to conduct a statistical analysis, but only for all species combined and not to compare means. To test the new disposable traps against larger populations, two additional experiments were run, both with treatments identical to those in Experiment 1. Experiment 2 was run at the Runzer Orchard from 7-13 Aug., and Experiment 3 was run at the Brar Orchard from 13-15 Aug. 
         [0037]    There was no significant difference in Experiment 1 between large standard control traps (Contech Inc.) baited with heptyl butyrate and 50% apple juice, and any disposable bag trap (2 or 4 small entry ports or two large entry ports) baited with the same lures (Table 1). Numerically, traps with two small entry ports were superior at a mean of two wasps per trap. 
         [0038]    The inventors considered the lack of difference to be significant because it appeared that the bag trap was competitive with the standard large control trap. Also significant is that about two hours after experimental set up, many of the disposable traps had already caught yellowjackets, while very few of the large control traps had done so. However, the inventors judged that further experimentation would be needed with larger populations. 
         [0000]    
       
         
               
             
               
               
             
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Ranked catches of yellowjackets (all species combined) 
               
               
                 in Exp. 1 testing prototype disposable traps of three 
               
               
                 different designs, Brar Orchard, Kelowna BC, 8-10 Jul. 2008. 
               
               
                 Respective percentages of 75 yellowjackets captured are: 
               
               
                   Vespula pennsylvanica  36.0%,  V. atropilosa  36.0%, 
               
               
                   V. vulgaris  22.7% and  V. consobrina  5.3%. 
               
             
          
           
               
                   
                 NUMBER OF 
               
               
                   
                 YELLOWJACKETS 
               
               
                 TRAP TYPE 
                 CAPTURED (MEAN ± SE) 1   
               
               
                   
               
             
          
           
               
                 Bag prototype, two small entry ports 
                 2.0 ± 0.5 
               
               
                 Bag prototype, four small entry ports 
                 1.5 ± 0.4 
               
               
                 Bag prototype, two large entry ports 
                 1.3 ± 0.6 
               
               
                 Standard large trap 
                 1.3 ± 0.4 
               
               
                   
               
               
                   1 ANOVA statistics: F = 0.44, df = 3.44, P = 0.7230. 
               
             
          
         
       
     
         [0039]    The results in Experiments 2 and 3 generally upheld those in Experiment 1 (Table 2). In Experiment 2, there were significant differences among treatments for  V. pennsylvanica  and all yellowjackets combined, but only for  V. pennsylvanica  were the differences great enough for a comparison between means. This comparison showed that traps with two large entry ports, or two small ones caught statistically similar numbers of yellowjackets as the standard large (control) traps, while those with four small entry ports caught significantly fewer yellowjackets than the controls. In Experiment 3, there was no significant difference among treatments, either for  V. pennsylvanica  or for all yellowjackets combined. 
         [0040]    On balance, the results of Experiments 2 and 3 showed that bag traps with two large entry ports performed more consistently than traps with two small entry ports (Table 2). Therefore, traps with two large entry ports were chosen for further commercial development. 
         [0000]    
       
         
               
             
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Ranked catches of yellowjackets in Exp. 2 and 3 testing prototype disposable 
               
               
                 traps of three different designs. Exp. 2, Runzer Orchard, Kelowna BC, 
               
               
                 7-13 Aug. 2008. Exp. 3, Brar Orchard, Kelowna BC, 13-15 Aug. 2008. 
               
               
                 Respective percentages of 163 yellowjackets captured in Exp. 2 are: 
               
               
                   Vespula pennsylvanica  68.7%,  V. atropilosa  25.8%, and  V. vulgaris  7.4%. 
               
               
                 Respective percentages of 351 yellowjackets captured in Exp. 3 are: 
               
               
                   Vespula pennsylvanica  90.67%,  V. atropilosa  4.7%, and  V. vulgaris  5.1%. 
               
             
          
           
               
                   
                   
                   
                 NUMBER OF 
               
               
                   
                   
                   
                 YELLOWJACKETS 
               
               
                 Experiment 
                   
                   
                 CAPTURED a,b   
               
             
          
           
               
                 No. 
                 SPECIES 
                 TRAP TYPE 
                 RANGE 
                 MEAN ± SE 
               
               
                   
               
               
                 2 
                 
                   V. pennsylvanica 
                 
                 Standard large trap 
                 1-11 
                 3.7 ± 1.0 a 
               
               
                   
                   
                 Bag prototype, two large 
                 1-11 
                 3.3 ± 0.8 ab 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, two small 
                 0-5  
                 1.5 ± 0.5 ab 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, four small 
                 0-2  
                 0.9 ± 0.2 b 
               
               
                   
                   
                 entry ports 
               
               
                   
                 All 
                 Standard large trap 
                 1-14 
                 5.2 ± 1.3 
               
               
                   
                 yellowjackets 
                 Bag prototype, two large 
                 1-16 
                 4.6 ± 1.2 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, two small 
                 0-8  
                 2.2 ± 0.8 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, four small 
                 0-5  
                 1.8 ± 0.4 
               
               
                   
                   
                 entry ports 
               
               
                 3 
                 
                   V. pennsylvanica 
                 
                 Standard large trap 
                 0-27 
                 8.7 ± 2.2 
               
               
                   
                   
                 Bag prototype, two small 
                 2-23 
                 7.7 ± 1.6 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, two large 
                 1-15 
                 5.7 ± 1.3 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, four small 
                 1-11 
                 3.7 ± 0.9 
               
               
                   
                   
                 entry ports 
               
               
                   
                 All 
                 Standard large trap 
                 0-30 
                 9.6 ± 2.5 
               
               
                   
                 yellowjackets 
                 Bag prototype, two small 
                 2-24 
                 8.3 ± 1.6 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, two large 
                 1-20 
                 6.4 ± 1.6 
               
               
                   
                   
                 entry ports 
               
               
                   
                   
                 Bag prototype, four small 
                 1-12 
                 4.2 ± 1.0 
               
               
                   
                   
                 entry ports 
               
               
                   
               
               
                   a ANOVA statistics Exp. 2:  V. pennsylvanica : F = 3.86, df = 3.44, P = 0.016; all yellowjackets combined: F = 3.26, df = 3.44, P = 0.030. Means for  V. pennsylvanica  followed by the same letter are not significantly different, Tukey&#39;s HSD test, P ≦ 0.05. 
               
               
                   b ANOVA statistics Exp. 3:  V. pennsylvanica : F = 2.05, df = 3.44, P = 0.120; all yellowjackets combined: F = 1.82, df = 3.44, P = 0.157. 
               
             
          
         
       
     
       Example 2 
     Test of Bag Traps for Flies 
       [0041]    Bag traps manufactured with two large entry ports were tested in comparison with a commercial plastic jar trap fitted with a cylindrical cross bridge open at each end for flies to enter, and with a cut out portion allowing flies to pass from the cylinder into the interior chamber of the trap. Both types of traps were baited with a protein-based lure (Contech Enterprises Inc., Delta, BC, Canada) in water with a dash of detergent added to ensure that captured flies sank below the surface and drowned. 
         [0042]    The experiment was run on a dairy farm in Delta, BC from 4-8 Sep. 2009. Eight randomized pairs of traps were suspended from fencing wire, with the between-traps distance ≧5 m. Captured flies in the suborder Brachycera (short-horned flies) were counted, but not sorted further by taxa. The mean catches were compared by a t-test. 
         [0043]    The results unexpectedly showed that the bag trap captured twice as many flies (mean±SE=86.5±14.0) as the commercial trap (mean±SE=42.0±7.6). This difference was significant (t=2.84, df=10, P=0.018) This result indicates that the bag trap as designed for yellowjacket wasps is also suitable for other insects. 
         [0044]    While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope.