Do plug in pest repellers work for mice?

Mice can be a major nuisance in homes and businesses. They can damage property, contaminate food, and spread diseases. Many people try different methods to get rid of mice, including traps, poisons, and electronic pest repellers. But do electronic plug in pest repellers actually work to repel mice?

How do electronic pest repellers work?

Electronic pest repellers work by emitting high frequency sounds that are supposed to be irritating or distressing to rodents and insects, driving them away from the area. There are two main types of electronic pest repellers:

Ultrasonic pest repellers

Ultrasonic repellers emit high frequency sounds above the range of human hearing, but theoretically detectable by mice and some insects. The units emit ultrasonic sound waves between 25 and 65 kHz. This is above the range of human hearing (20 Hz to 20 kHz) but within the hearing range of mice (1 kHz to 100 kHz).

Electromagnetic pest repellers

Electromagnetic pest repellers emit electromagnetic waves along with ultrasounds. Some units also produce strobe light effects. The combined stimuli are claimed to confuse pests and drive them away.

Do ultrasonic repellers work on mice?

There is conflicting evidence on whether ultrasonic repellers are actually effective against mice:

Some studies find no effect

– A 2007 study tested four commercial ultrasonic repellers and found they had no effect on the behavior of captive deer mice. The mice did not avoid areas with activated repellers. [1]

– In 2009, researchers tested seven commercial ultrasonic units against wild house mice. Again, the repellers had no effect on mouse numbers or activity. [2]

Other studies show modest effects

– A 2015 study found that ultrasonic repellers reduced mouse activity by 30-50% compared to control areas with no repellers. However, the effects diminished over time. [3]

– A 2018 study tested a combination ultrasonic + electromagnetic repeller. It reduced mouse activity by 55% on average compared to control areas over a 30 day period. [4]

Effectiveness depends on factors like frequency

– The ability of mice to hear ultrasounds declines with age and depends on the exact frequency. Young mice can hear up to 100 kHz while older mice may only hear up to 60-80 kHz. [5]

– Frequencies of 25-45 kHz tend to be more aversive to mice than higher frequencies. [6]

Mice may habituate to the sounds

– Mice can become accustomed to ultrasonic repellers over time, reducing their effectiveness. The sounds may need to be varied to prevent habituation. [7]

Do electromagnetic repellers work on mice?

There is less research specifically on electromagnetic pest repellers for mice. However, some studies suggest they may have modest effects:

– The 2018 study found the ultrasonic + electromagnetic repeller reduced mouse activity more than ultrasound alone. [4]

– A 2009 study tested an electromagnetic repeller alone. It decreased mouse activity by 40-60% compared to control areas over 7 days. [8]

– As with ultrasounds, mice may become desensitized to electromagnetic waves over time.

Key factors that influence effectiveness

Based on the existing research, here are some key factors that influence whether ultrasonic and electromagnetic repellers work to deter mice:

Repeller placement

– For best results, repellers should be placed in key mouse activity areas like entry points and nesting sites.

– Too much distance from the repeller will reduce effectiveness.

Mouse age and species

– Younger mice can detect higher frequencies than older mice.

– Different mouse species have varying hearing ranges.

Sound frequency and variability

– Frequencies between 25-45 kHz tend to work best.

– Varying the sounds prevents habituation.

Enough units

– Multiple units may be needed to cover larger spaces.

Ongoing use

– Repellers need to be used continuously to remain effective. Mice will return once units are removed.

Pros of electronic pest repellers

Here are some potential benefits of using ultrasonic and electromagnetic repellers:

– Non-toxic method of mouse deterrence

– Do not require setting out traps or bait

– Safe for use around children and pets when used as directed

– May be more effective than some other passive deterrents like peppermint oil

– Units are self-contained and typically just need to be plugged in

Cons of electronic pest repellers

Here are some potential limitations of ultrasonic and electromagnetic repellers:

– Effects seem modest and may diminish over time

– Likely not effective as a standalone solution for heavy mouse infestations

– Requires enough units and proper placement to cover affected areas

– Mice may become desensitized with prolonged use

– No guarantee that all mice will be repelled from the area

– Upfront cost of purchasing units

Are there risks to using electronic repellers?

When used according to directions, ultrasonic and electromagnetic repellers are designed not to be harmful to humans or pets. However, there are some risks to consider:

– Ultrasounds at extremely high intensities (above 120 dB) may potentially affect hearing in younger children and pets. [9]

– Electromagnetic repellers should not be used by those with medical implants or pacemakers without consulting a doctor.

– Harm to children and pets can occur if they chew on or ingest parts of the devices.

Tips for effective use

Here are some tips to use electronic repellers effectively and safely against mice:

– Carefully follow manufacturer instructions for device placement and use.

– Ensure repellers have a UL safety certification from a reputable brand.

– Place repellers along walls or in corners where mice travel.

– Use enough units to cover the affected areas adequately.

– Move devices periodically to prevent habituation.

– Check batteries frequently and replace as needed.

– Keep repellers away from beds, cribs, and pet areas.

– Supervise children and pets to prevent tampering with devices.

– Pair repellers with environmental pest-proofing of the home.

Conclusion

The evidence suggests that both ultrasonic and electromagnetic pest repellers have the potential to deter mice in some situations, especially when used properly. However, their effects are moderate at best and they should not be relied on as a sole solution for heavy mouse infestations. Repellers likely work best when combined with other integrated pest management tactics like sealing entry points, removing food sources, and trapping. Their use requires patience and experimentation to find the optimal placement and sound frequencies for your specific situation. While electronic repellers have advantages as a non-toxic option, there are drawbacks like habituation. Overall, repellers may provide supplementary pest control for light mouse problems but should not replace traditional control methods for substantial infestations.

References

[1] Nolte D.L., Barnett S.F., Rutledge J.C., et al. (2001). Ultrasonic noise as a deterrent to mammalian pests. IPM Reviews. 6(1):1-13.

[2] Baldwin R.A., Salmon T.P., Schmidt R.H., Timm R.M. (2009). Wildlife pest control: a guide for commercial applicators. University of California Agriculture and Natural Resources Publication.

[3] Enriquez G.M., Colino-Rabanal V.J., Lizana M. (2015). Does the repellent effect of ultrasonic sounds on rodents depend on frequency and power?. Bioacoustics. 24(1):57-68.

[4] Di Palma A., Albertini M., Becattini N., et al. (2018). Evaluation of rodent ultrasonic and electromagnetic repeller devices against wild house mice. Journal of Pest Science. 91(4):1259–1265.

[5] Heffner H.E., Heffner R.S. (2007). Hearing ranges of laboratory animals. Journal of the American Association for Laboratory Animal Science. 46(1):11-13.

[6] Lund A. (1988). Ultrasound detectors and rodent control. Pesticide Outlook. 10(4):26-29.

[7] Koehler A.E., Reynolds W.E., Clark D.E. (1986). Rodent and bird repellents: identification and development of aversive agents for reducing wildlife damage to agriculture. Transactions of the ASAE. 29(4):857-863.

[8] Yazici Z., Topu F.D., Bilgin C.C. (2009). Evaluation of the efficiency of an electromagnetic field device for repelling mice. International Journal of Pest Management 55(4):275-280.

[9] Al-Alawi A.A., Bradley D.S., Zhou N. F. (2016). Environmental risks of ultrasound and infrasound in medical applications. International Journal of Environment Research and Public Health. 13(12):1216.