Deer Management Solutions

About Deer-Departed : Deer Departed News : October 2007

October 1, 2007 20:54 - Deer Psychology 101 Fall Habits

  • Why do deer run out in front of your car?
  • Why do they seem to target your plants for eating instead of your neighbors?
  • Why do they leave the leaves on your trees, but instead damage the bark?
  • Why are there only one deer at times, then at other times of the year several?

Understanding why deer do what they do is the first step in deciding what type of deer repellent or deer deterant you need to consider buying or even making yourself.
Since it is October 1, lets start with deer psychology in the Fall of the year.

In the fall, the bucks come to live with the does and the fawns. The white-tailed deer breeding season is in the fall and part of the winter from approximately October to January. This is called the "rut". During the rut, bucks have theri highest levels of testosterone and this causes them to wander into residental areas where they would not normally be found. This also causes them to chase does across a busy highway.

The buck does what is called "signposting", scraping and rubbing trees. Ths is to leave his scent on the ground and the trees and also to rub the velvet off his antlers.

Deer reach their peak weight in mid-October. Fall brings new sources of food for deer. Green grass and landscape plants are replaced by acorns, seeds, and grains.
Hunting season is in the fall in most states, scaring the deer and causing them to run into the highways to avoid hunters.
Fall is a dangerous time for deer and for motorist and both need to be aware of the danger of the other.

October 13, 2007 17:17 - Deer Alert Devices

I mentioned in the last article that fall was the most dangerous time to be driving in high deer poplulation areas. Insurance companies have vehicle-deer collisions estimated at 1 million to 1.5 million per year. Approximately 300 people and 1 million deer are killed by a vehicle each year.
State Farm Insurance claims that drivers in Pennsylvania experienced more deer accidents than any other state in 2004. The top five states for vehicle-deer collisions were Pennsylvania, Michigan, Illinois, Ohio, and Georgia. Average vehicle damage was about $ 2,600 when there were no injuries and about $11,000 when someone was hurt.
Let's talk about the two types of deer whistles for cars.
There are basically two types of deer whistles, air velocity operated and electronic.
Air velocity whistles are the cheapest type to buy, but tend to have some drawbacks with being clogged by insects, dirt, snow, and anything else that accumulates on the car. They also tend to fall off easier and can be removed from the car by some types of car washes. Research seems to point toward these being less effective at lower speeds.
Electronic whistles are more expensive than the air types and need an electric source, usually plugging into a cigarette lighter, hooking to the battery, or being hard wired under the dash board. The electronic types such as The Electronic Deer Whistle, AA Portable Deer Alert, Design Tech Deer Alert, or Hornet, have an effective range of 1,500 feet and speed doesn't seem to affect their results. They are engineered to produce both a ultrasonic frequency that would be heard by animals, and a sonic frequency heard by humans and large animals like deer. The requirement for wiring would be the draw back to the electronic types, though the Portable Deer Alert does allow you to run the wires though a door or window without any drilling.
Next time we will look at some of the research that has been done to study whether or not these two types of whistles work and if so, which one works best.

October 18, 2007 19:16 - Car Whistles -Some research says Yeah.

Yeah or Nay?
The effectiveness of deer whistles has not been studied thoroughly in a scientific way. Much of the research was not done using formal statistical methods, therefore there are dramatically different results from the few studies that have been done.
One method that has been used to evaluate the effectiveness of deer whistles includes the comparison of accident data for state police vehicles. This type of research or documentation typically had a small sample size, a control group was not set up equally, and the length of time of the study was not considered. There are many testimonials on several sites that sell deer whistles from people that believe the whistles saved their lives. While not research studies, these also have to be taken into consideration.
Pro-Whistle Studies: In New York the Sheriff’s Department in Onodaga County mounted deer whistles on 55 patrol cars. In an October/November 1988 newsletter article about the devices, it was reported that only two patrol cars had struck deer since 1986 and that five others had sustained minor damage avoiding collisions with deer. Before the installation of the devices the county sheriff’s department experienced about 10 accidents with deer each year. Gosson, J.T. Deer Whistles Prevent Costly Accidents. The National Sheriff. Vol. 40, No. 5, October/November 1988.
In Modoc county California 1,648 whistles were distributed to people in the county by the local government and their license plate numbers recorded. They used two types of air actuated whistles and one type of electronic whistle. None of the 1,648 cars with whistles hit deer. Of the other 6,623 cars in the county that didn’t have whistles, there were 29 collisions with deer reported. Statistically compared with the expected number of deer collisions based on the last 7 years of reported accidents for the county, the analysis indicated a reduction of 99.6% for deer-vehicle accidents. Tracy, T. A Program to Reduce Collisions with Animals. Final Report to California Office of Traffic Safety for Project RS0110. Modoc County Road Department, Alturas, CA February 2003.

Next message the Naysayers.

October 19, 2007 13:37 - Car Whistles Some research says Nay

Last entry I referenced research that suggested that car whistles do work to help reduce deer-vehicle accidents. This entry I want to review a few articles that came to completly different conclusions.
An article from the mid-February 1993 Farm Journal stated the Ohio State Police, after installing deer whistles on their patrol vehicles, did not experience a DVC reduction.
In another article, it was stated that the Georgia Game and Fish Department had not observed, during hundreds of encounters, any deer response to vehicles with deer whistles installed.
These articles were reviewed by The Insurance Institute for Highway Safety. Deer, Moose Collisions with Motor Vehicles Peak in Spring and Fall. Status Report. Volume 28, Number 4, April 3,1993.

During January and February of 1990, two researchers Romin and Dalton studied responses of mule deer to vehicle- mounted deer whistles. Two brands of air-activated whistles were separately mounted to the front of a truck and the truck was back-and-forth down roads. The respose of mule deer was recorded.. Overall, approximately 39 and 31 percent of the deer responded to the vehicle either with or without the whistle mounted, respectively. Therefore, 61 and 69 percent didn't respond at all to the vehicle. Romin, L.A., and L.B. Dalton. Lack of Response by Mule Deer to Wildlife Warning Whistles. Wildlife Society Bulletin, Volume 20, Number 4, 1992, pp. 382 to 384.
Also, on the nay side, a study by an acostics researcher, concluded that many whistles did not produce the frequency of sound that was needed for the deer to hear. It also concluded that the contour of the road played a role in whether the whistles worked or not. Scheifer,M. P., D. G. Browning, and L. M. Collins-Scheifele. Analysis and Effectiveness of "Deer Whistles" for Motor Vehicles: Frequencies, Levels, and Animal Threshold Responses. Acoustics Research Letters Online, Volume 4, Number 3, July 2003, pp. 71 to 76.

Next entry I will give you my conclusions and opinions.


October 26, 2007 18:21 - Deer Whistle Conclusions

My first conclusion is that more research be done. I know it is hard to conduct research on wild animals, but it is possible. With 1 billion dollars being spent each year on repairing damage from deer-vehicle accidents, it is hard to believe that the insurance companies or other groups with a lot to loose, wouldn't do some controlled studies with captive deer.
The research that has been done has been inconclusive. Much of it was not done using proper statistic procedures. There were other studies done that weren't mentioned because they were done in other countries and couldn't be validated and also didn't seem to be done using replicatible designs.
My personal conclusion is that they may or may not work depending on circumstances like the speed of the car, the straightness of the road, the type of whistle used, and other variables.

After reading several pages of customer reviews on many websites, I think that it would be good to put them on your vehicle. It certainly couldn't hurt, even the most expensive of these is very cheap when you compare it to the deductible you would have to pay if you were in a collision with a deer. Not to mention any possible trips to a hospital.
The main thing to remember is that you can't depend on whistles or anything else to keep the deer from running out in front of you or moving out of the way. A false sense of security could be dangerous. You always need to be alert and slow down in high deer trafficc areas.
Please read the list of driving tips at Deer Avoidance Driving tips
Be careful out there, especially at daybreak and dusk.

October 28, 2007 19:16 - What about deer repellents?

Deer repellents have proven effective in several research projects.
There are two basic types of repellents. The first affects the taste of the plants, the second effects the odor around the plants and either repulses the deer or scares them.
Common taste repellents include capsaicin which is found in hot peppers. Bloodmeal is one ingrediant used as an odor repellent. Rotten eggs are used as both a taste and odor repellent.
Scare repellents include coyote urine, and human hair.

Before applying a deer repellent, think about these things.
  1. How much will it cost compared to how much you will save? How often to I have to apply it, and do I have time to keep re-applying? Is it OK if I only get partial control, or do I need 100% control like a 10 foot fence would provide? Are the deer eating the plants or rubbing just rubbing them? Do you need it to just control deer or does it also need to work on rodents or rabbits?

There are many brands of repellents and you can even make your own if you can stand the smell and can be safe enough handling extrememly hot peppers that could burn your skin. It has been observed that these types of chemical repellents work best if they are applied to less prefered plants. If there are a lot of deer and very little other plants for the deer to eat it may take a combination of several strategies to protect your plants.
We'll talk more about deer repellents next time.

September 2007 «  » November 2007


RSS Feed For This News

Deer Departed News | Archives