Biological Control

Biological Control

Biological control typically involves the introduction of a disease or predator to manage

a pest population. Control with diseases is rarely used due to the risk of unexpected consequences. Predator control, such as the release of hawks or free-range house cats, although widely praised by the public, rarely works to achieve desired goals. Predators rarely reduce prey populations low enough to meet public expectations.

Figure 26. A BatCone™ can be used as a one-way door to exclude birds. Photo by Jim Dreisacker.

Fertility Control

Fertility control essentially is birth control for Before installing a one-way door, conduct a

wildlife. The public is quite tolerant of fertility thorough inspection to make sure all young that

control and considers it to be humane. are present are mobile. One-way doors only are

Research on birds suggests that at least 60% of effective if the animal can find and use the exit,

the eggs must be infertile for natural mortality but cannot find or force its way back through

to outpace reproduction. Fertility control will the door or find another way into the building.

not reduce bird numbers quickly, as it relies on If a mother has been separated from her young

natural mortality.

and they are still inside, she will be motivated to find or create another entrance. If an adult

Fertility control falls into two categories, bird cannot reach its young, they will die and

physical and chemical. Physical fertility control physical and chemical. Physical fertility control

Chemical fertility control relies on a product to inhibit an egg’s ability to hatch. For example, the application of corn oil to the surface of a Canada goose egg will starve the embryo of oxygen. Nicarbazin is an active ingredient that birds such as pigeons consume with treated bait, preventing them from laying fertile eggs.

Be aware that the addling (shaking) and oiling of Canada goose eggs requires a permit from the Illinois Department of Natural Resources. Landowners may designate third party implementation, such as a PMP, but the permit must be in the landowner’s name. Permits are time-specific. The USDA-APHIS-Wildlife Services program provides landlowners assistance in obtaining federal depredation permits from the U.S. Fish and Wildlife Service. See information at http://www.aphis.usda.gov/wps/portal/aphis/o urfocus/wildlifedamage .

These rules are subject to change. Disposition of Problem Birds

In recent years, an increasing number of people have become concerned with the treatment of animals, even those considered pests. Although views on this issue vary, wildlife should be treated with respect, and animal suffering should be minimized in ways that balance effectiveness and practicality.

Frequently, people want problem birds to be transported elsewhere and released rather than killed. Before discussing this option in more detail, we need to explain some terms.

Relocation and Translocation of Wildlife

Relocation refers to the movement of an animal from one spot to another within its home range, such as rescuing a bird trapped in a chimney flue and releasing it outside the house. Translocation is the movement and release of an animal to an area outside its home range. For example, transporting a Canada goose from Chicago to Springfield and releasing it is considered translocation.

It should be immediately apparent that relocation of birds is practical only in rescue situations or when efforts have been made to exclude birds from returning to the site. Simply moving birds a mile or two, without installing exclusion materials, will not work because they will quickly return to the site. Birds are too mobile for relocation to work to be effective.

Translocation may appear to offer the possibility of a humane solution, but efforts rarely have achieved the desired results. Even though birds are moved hundreds of miles away, they frequently return. One also must consider the potential for disease transmission and stress to the birds involved in translocation. All in all, relocation and translocation are effective only under limited circumstances.

Lethal Control

When discussing the humane treatment of wildlife, PMPs should keep three terms in mind -- capture method, humane killing, and euthanasia. Capture method refers to the use of techniques to take possession of free-ranging animals, such as trapping and shooting. Sometimes the capture method does not kill, as in the case of a cage trap for birds. In other instances, such as hunting, the capture method results in the death of the animal.

Humane killing refers to methods employed to possible. Keep animals separate from each intentionally and rapidly kill animals, but not

another and in a quiet area. Cover cage traps painlessly as required by the euthanasia

with a blanket to keep the animals calm. standard. Shooting of birds is an example of a

Reduce noise to reduce animal stress. Handle capture method that is a form of humane

animals gently and only as necessary before and killing.

during the euthanasia process. Euthanize only one animal at a time. Prevent animals from

Euthanasia refers to the killing of animals in a witnessing the euthanasia of other animals. manner so they do not experience pain or

More detailed information on euthanasia can stress. Use of narcotics by a veterinarian to end

be found at:

the life of a pet is one example of euthanasia. http://www.icwdm.org/wildlife/euthanasia/def

Understandably, euthanasia is the preferred

ault.aspx .

method to kill animals whenever lethal control is required. However, euthanasia often is

AVMA-approved Methods

impractical, as it frequently requires the animal to be under the direct control of a PMP, such as

Shooting

in a cage trap. Therefore, the next best option is Shooting can be painless and sometimes is the the use of humane killing. In some situations,

only available method to humanely remove an shooting, which simultaneously captures and

animal. Before discharging a firearm, you must: kills birds, may result in less suffering than using

1. be able to handle a firearm and live-capture techniques followed by a

ammunition safely,

euthanasia technique because wild animals can

2. comply with local laws and regulations experience stress in cage traps. Contrary to

regarding the transportation and discharge popular belief, cage traps may not be the most

of firearms, and

humane solution in every situation.

3. be capable of producing a quick death by a shot to the brain or other vital area of the

Humane treatment of wildlife is a complex issue that often does not have simple solutions.

animal (Figure 27).

Always choose methods that reduce animal suffering and are practical. Due to the emotional involvement people have with wildlife, all killing of wildlife, whether by capture device, humane killing, or euthanasia, should occur away from public view. Failure to

follow this advice can result in unwanted public

Figure 27. Proper shot placement for shooting birds with

scrutiny of WDM activities.

bullets. Head shots are considered euthanasia. Other locations are considered humane killing. Image by Bob

Euthanasia of Animals

Noonan.

When euthanasia is required, we suggest using