Determining how to live with deer has been one of the more controversial issues in Riverwoods. Although no one can dispute their grace or beauty, deer can present a number of problems, including traffic accidents and very significant pressure on the plant life of our area. While some contend that the deer population has exploded in recent years, others say the diminution of their natural environment, caused by more and larger homes, vast lawns, and habitat-consuming amenities has created the problem. Most environmental experts believe that an overpopulation of deer exists in much of the Midwest and Northeastern United States. The debate has centered around two issues: (1) the seriousness of the overpopulation; and (2) the appropriate manner of addressing the overpopulation. Those who contend overpopulation is a serious problem cite as evidence supporting their view extensive damage to vegetation by over-browsing, auto accidents, transmission of deer-tick borne Lyme Disease to humans and pets, and deer deaths due to accidents and starvation.
Where once there was plenty of open space for them, deer now are damaging both the woodlands ands our gardens in order to survive. In addition, having long ago exterminated the large predators, such as bobcats and wolves, which would have controlled herd numbers, we are left with no natural alternatives for achieving a healthy balance. (Although coyotes may take down a few fawns or sick or injured deer, these occurrences do not significantly reduce deer numbers.)
When normal food sources cannot sustain the deer population, they search elsewhere. Starving deer will eat almost any vegetation, including evergreens, many woodlands plants and even tree bark. Most vulnerable are the young trees, which are necessary for woodlands regeneration. This damage to woodland vegetation can have significant effects. If the deer consume the woodlands more rapidly than they are regenerated, there is a steady reduction in the size, quality and diversity of the woodlands. Deterioration of the woodlands has many side effects, including destruction of animal habitats, such as reduced nesting places and food sources for birds. Reduction in bird populations results in an increase in undesirable insect populations. Some animals, such as mice, can adapt better than others to changes in habitat. Those populations may increase while the diversity of the animal population decreases.
Control efforts. The Lake County Forest Preserve District monitors the deer population, primarily through use of aerial surveys in the winter when the deer can be observed. Although controversial, sharpshooters occasionally have been hired to cull a herd. Other control efforts, none completely successful, have included trapping and transporting deer to distant forest preserves; contraception and surgical sterilization; fencing; netting; and use of various deer repellant materials around vegetation. Trapping and sterilization result in high mortality rates because of trauma. Most contraceptive drugs are difficult to administer, partly because two injections separated by several days are required. Fencing and netting are highly effective for the protected areas, but they are impractical for large areas, can be unsightly and, perhaps most significantly, divert deer to ever-smaller unprotected browsing areas where even greater damage occurs. Deer repellants, while effective, require frequent reapplication. In addition, deer can become adapted to the repellants.
Plant selection is a possible solution. When landscaping or gardening, it helps to choose plants “not favored by deer” rather than delicacies such as roses or geraniums or yews. These less palatable plants are often fuzzy or strongly scented, or toxic, such as lamb’s ears (Stachys byzantina), catmint (Nepeta mussinii) , and monkshood (Aconitum napelllus). Lists of such plants are readily available. Start with the Chicago Botanic Garden, which is always a good resource. The Riverwoods Plant Committee does its best to offer an assortment of these plants and shrubs in their yearly sale. Be sure to give them a try. But, keep in mind that sometimes the deer haven’t read the list and occasionally a deer will try your bloom before realizing he/she doesn’t like it.
Physical barriers sometimes help. These can be effective but also costly and some fence materials are foreign to the open space ambience of Riverwoods. In addition, physical barriers may simply direct the animals to your neighbors’ unfenced properties or to the forest preserves. Regardless of fencing material, and although deer are said to jump as high as eight feet, they will usually avoid a much lower barrier if they cannot see where they will land. Since the Riverwoods ordinance limits fence heights, try to design one that uses brush and plantings to obscure the landing area.
Should you come across an injured or dead deer, call the Riverwoods Police Department, which will advise you based on the location of the animal and the circumstances. Hunting is not permitted in Riverwoods so if you observe evidence of it, notify authorities.