Best practices
for nuisance wildlife control operators in New York State

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Ch 5: Step three: Do it - Lethal techniques

Lethal traps

Body-gripping traps are spring-loaded lethal traps available in many sizes. They're usually square, but some specialized models are round. Body-gripping traps are often called "Conibears," which is the name of a popular model manufactured by Oneida-Victor, Inc., but there are many manufacturers. There are also new, smaller designs, including some with one-way triggers, which are more selective, and traps designed specifically for squirrels.

"Magnum" or "zero tolerance" versions are also available. This model is stronger and its jaws close very tightly, so it often kills faster and more consistently than the standard trap. This may increase the chance of a proper strike with squirrels or raccoons, or other small or flexible animals that might pull back if there's a slight gap between the jaws. Magnum versions are very strong—a #220 Magnum body-gripping trap could break bones—so be very careful when setting the trap. Consider using setting tools and safety devices.

To set a body-gripping trap, you must compress the spring until its tips nearly meet at the rotating point of the jaws. Then hold both jaws open and fit the dog (a.k.a. the "trigger hook"), which is notched, into the notch located on the trigger. Once securely in place, the dog holds the jaws open. In its correct position, the jaws of the trap close on the top and bottom of the animal. Stabilize the trap to keep it in this top-to-bottom strike position, and to ensure that it can't easily be knocked over. Anchor the trap, too. (These traps are lightweight enough to be carried off by predators attracted by the captured animal.) In New York, the jaw spread of a body-gripping trap set on land cannot be greater than 5 3/4 inches (the jaw spread is the distance between the two jaws when the trap is set).

Some models of body-gripping traps, usually those with two springs, have safety hooks that hold one spring while you're setting the other. If you use a safety hook, remember to release it when you're done setting the trap, so the trap can fire.

When an animal passes through the jaws of the trap, it moves the trigger, which dislodges the dog from its notch and springs the trap, closing the jaws around the animal's neck or chest. Ideally, this trap catches the animal directly behind the head, snapping the part of the spine that's in the upper third of the neck (called the "cervical spine" area). A proper hit provides a quick death.

If you are trapping raccoons, skunks, squirrels, or woodchucks, modify the trigger to help to ensure a top-to-bottom strike (which is more humane) and prevent the animal from refusing to enter the trap. These species don't like to have anything brush against their eyes or whiskers, so separate the trigger and center it on the bottom of the trap.

As with all lethal techniques, care is needed to make sure that only the intended nuisance animals are caught. Body-gripping traps are often set in front of the animal's entrance hole because the animal must pass through the jaws of the trap to be captured. This way, only an animal entering or leaving the hole will be caught. If necessary, guide the animal into the trap. Use hardware cloth to reduce the size of the entry hole (shown in the photo) or to block escape routes.

This tool often provides the quickest way to remove a raccoon or squirrel from an attic. Another advantage is that non-target animals are not nearly as likely to be on the roof as they are on the ground. But this trap is not appropriate for all settings.

Use extra caution if you're setting a body-gripping trap on the ground, because of the risk to people, pets, and other wildlife. You can modify your technique and your equipment to minimize these risks. Here are some suggestions.

Cover the trap and burrow entrance

Let's say you've been unsuccessful trying to catch a woodchuck in a cage trap, or you need to trap many woodchucks. A body-gripping trap, if used cautiously, may be the right tool. Dig out the opening to the woodchuck's den a bit, so you can set the body-gripping trap in the burrow's entrance. The trap should be attached to a stake in the ground. Cover the burrow entrance and the trap with a large, loosely attached piece of hardware cloth, or with a box. When the woodchuck leaves its den, it will spring the trap, but an animal poking its head into the burrow entrance wouldn't.

Place the trap in a container (a vertical cubby set, deep-notch box, or bucket with small hole)

Three views of a body-gripping trap placed in a vertical cubby set. Above, left: The vertical cubby is attached to the tree at about five inches off the ground, to make sure that a dog can't reach up into the box and spring the trap. Right: In this set, the trap was held in place by friction, so when it sprung, the trap fell out of the box. You can anchor the trap so it will remain in the cubby after it's sprung, too. Bottom: Bait is placed on a shelf near the top of the box. Notice the body-gripping trap in its set position. You can see the trigger and jaws within the box, and the spring sticking out to the left.

One way to lower the risk of catching an unintended species is to use a vertical "cubby" set, shown in the photographs. This is a baited box that's open on one end, with the trap set well inside, usually held in place by friction between the coilsprings and the narrow notch in the box. You must use a model with two coilsprings, because one with a single spring won't stay in place. Make sure the open bottom of the box is no more than five inches off the ground. If a dog investigates, it may be hit on the nose, but it's unlikely that the trap would capture the dog. Cats cannot easily enter a vertical cubby set.

The deep-notch box is an alternative to the vertical cubby set. It's set horizontally on the ground. If you're using a #220 body-gripping trap, the notches should be 8" deep. The trap is placed in the midpoint of the notches, which hold the trap in place. Make sure the trap is securely anchored. Center the trigger on the top of the trap. Bait should be placed deep inside

By restricting the size of the opening, you reduce the risk that a dog will spring the trap. The opening of a deep-notch box should be no more than 7" high.

the box, at least 6" behind the trap. The top of the deep-notch box is blocked with a piece of wood (see photo). By restricting the size of the opening, you reduce the risk that a dog will spring the trap. The opening of a deep-notch box should be no more than 7" high.

Although the vertical cubby set and the deep-notch box work on the same idea, and are interchangeable, they have different strengths. The vertical cubby is less likely to attract cats (unless you've used the wrong bait) and is even more dog-proof than the deep-notch box. Sometimes, a raccoon will avoid a vertical cubby but investigate a deep-notch box. Some NWCOs prefer one design over the other, as well.

Another option is to place the body-gripping trap inside a plastic bucket that has a restricted opening. The bucket can be round or square, as long as it has a lid. An opening no larger than 7" is cut into the lid, slightly off-center. It works like a deep-notch box, only it's made from plastic instead of wood. Have some extra lids prepared, in case one is damaged or lost.

Use baits that selectively attract the nuisance animal

Both marshmallows and sardines will attract raccoons, but marshmallows won't entice cats, so that's a safer bait to choose if you must trap in an area where there are free-roaming cats. Mice will be attracted by many baits that are of varying appeal to other species, but you could avoid using bait entirely. Tie a cotton ball to the trigger instead. That's an attractive bit of nest material to a mouse, but cotton is of no interest to many other species. Whenever possible, use baits and lures that will attract only the nuisance animals.

Use a trap with a one-way trigger

The one-way trigger rests against the bottom jaws of the trap and only moves freely in one direction. In this illustration, the animal would have to move from left to right to lift the trigger and spring the trap. An animal coming from the other direction might bump the trigger, but it's not likely to lift it high enough to spring the trap.

Compare the trap with the one-way trigger to the standard model shown below it. See how that trigger swings freely? It can spring the trap regardless of which way the animal approaches. That means it can catch an animal on its way out of its den, which is what you want—but it might also accidentally capture an animal that stopped to investigate. In some cases, that might be the wrong animal.

There are commercial traps with one-way triggers, but you can modify an existing trap, too. For example, you can add a 220-wire trigger to a #120 body-gripping trap.

Next Section (other lethal traps)

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