Wildlife Management
The key to success in managing damage caused by wildlife is first and foremost to correctly identify the species doing the damage. Rabbits, for example, have strong front teeth which cause pruning like damage (a clean cut). Usually a sharp 45 degree angle that is at or below one foot off the ground are good indicators of rabbits. Deer, on the other hand, have poor front teeth and tend to grab and pull the vegetation causing scraping damage most often between one and five feet off the ground. Deer also leave scraping marks from rubbing which will also be higher on the trunk than most rabbits can reach. Both animals cause damage but the evidence clearly indicates the culprit which will determine the type of management approach to use. Putting up a 2’ fence to deter rabbits would not faze the deer and installing a 12’ fence is an expensive overkill to maintain the rabbits.
Whatever your approach it is important to be proactive and persistent. The use of a good wildlife guide can be beneficial in identifying species. Author Mark Elbroch has wonderful guides among which are: Mammal Tracks and Signs and Bird Tracks and Signs. These offer helpful information on a multitude of animals and should be a good source in narrowing down the kind of pest you are dealing with.
The first step in wildlife management should be cultural modification. Can you change the way you do things? For example, placing a bungee cord on trash cans may eliminate raccoons. Storing dog food (that may be in your garage) in sealed containers can deter mice and chipmunks. Eliminating hiding spots or areas where animals may burrow can keep populations down. Beyond that it is best to divide your yard into different zones based on the type of problem and the control strategies used. One zone may be for “non-lethal” methods such as chase, scare or deter. Another “lethal zone” will involve more drastic measures. Examples of each may include:
Non-lethal control:
Noise/harassment – such as with a dog to chase wildlife away. Randomness is the key, if the harassment is always the same then wildlife can adapt.
Taste repellent – such as sprays applied to leaves. This works well on ornamentals.
Smell repellents – such as moth balls, Irish Spring soap or even Milorganite scattered around the area.
Capture and release – this has a relatively low success rate. Animals tend to return to the area or die in the new release location.
Lethal control:
Poisons are typical and can be effective. However, it’s important to be mindful that poisons don’t discriminate. Any animal can ingest the poison and the bodies of the victims can hold the poison in their tissues. Thus, anything that eats the dead animal may also succumb to the poison. This includes neighborhood pets or more “desirable” wildlife visiting your yard. Poisons can be slow to act allowing the victim to retreat to an inaccessible area (such as den, tree or inside a wall) before they die. Decomposing carcasses are sure to attract even more pests. Traps to kill can also be effective but can be rather cruel depending on the method of trapping.
Wildlife, like weeds, are an ongoing issue for gardeners and homeowners. If you are having constant problems with wildlife in your yard do your research to learn about the problem and the offender. The more drastic the measure you need to take, the more important it is to be respectful of the attitudes and opinions of any neighbors. If you are using poisons you should be familiar with regulations and laws that govern the species you are targeting. It is also good to acquaint yourself with the agencies and services which might be valuable resources. There are many websites dealing with damage from wildlife, some specific to Wisconsin are listed below.
Wildlife Ecology & Damage Management wildlifedamage.uwex.edu
Wisconsin Department of Natural Resources dnr.state.wi.us
Internet Center for Wildlife Damage Management icwdm.org