Long, thin bodies resemble those of the stick insect and can measure up to 12 cm from pincers to wingtips.
Dobsonflies are found primarily outdoors near large bodies of water. Indoor infestations would not be possible, since they are incapable of reproducing indoors..
Adults typically do not feed. They are attracted to lights and may been seen resting on walls near outdoor light fixtures. Larvae are aquatic and predators of other aquatic organisms. They possess strong mandibles which are capable of delivering a very painful bite if handled. Fisherman sometimes us them as bait for fish.
Although the pincers of the male dobsonfly appear threatening, they are harmless. Rather, female dobsonflies use their smaller jaws in self-defense and are capable of piercing the skin if handled. While these bites can prove mildly painful, dobsonflies are not known carriers of any diseases. Dobsonflies may emit unpleasant odors when threatened.
Reducing attraction of these flying insect problems reducing attraction of these insects to buildings by manipulation of lighting. Indirect lighting should be used where practical, so that the actual source of light is shielded from the area or direction from which the insects may come (if this direction can be determined). In many cases it is possible to use spot lights mounted at a considerable distance from the building. In this way insects attracted to the lights are attracted away from the building. This procedure is more likely to succeed in cases of buildings with dark-colored or dull finished masonry rather than light-colored or glass and metal exterior surfaces, which strongly reflect remote light. Try to shield lights so they are not visible in the surrounding area from which the insects may come. Light fixtures inside buildings should be placed so insects outside are unlikely to see the lamp itself. Excessive illumination should be avoided wherever possible.
There is little, if any evidence that any light is repellent to insects, but yellow is generally the least attractive to most insects. Avoid insect-attractive lights, especially mercury-vapor lamps and black lights (BL or Ultraviolet). Green fluorescent tubes are very attractive to many leafhoppers. Sodium-vapor or other lighting systems that have a pink, yellow or orange glow will be less attractive than the bright whitish or bluish mercury-vapor or fluorescent lights. Careful observation, some experimentation an application of common sense in manipulating lighting can often result in considerable reduction of a building’s attractiveness to insects.
Light Management:
- Move light source away from building.
- Replace Mercury vapor with Sodium vapor lights.
- Lower wattage bulbs.
- Replace lights producing high heat levels.
- Install shields over lights.
- Discuss security concerns with safety officers.