Image of a Racoon getting in the trashSkunks Eating from a Pet's Food DishImage of a Coyote eating food scraps littered on the edge of a roadwayImage of an Opossum eating pet food from a food dish outside

There are three main reasons why trapping does not work: the vacuum effect, the availability of resources, and nature's ability to adapt.

Vacuum Effect

Trapping and removal of wildlife has proven to be ineffective. One of the main reasons is called the vacuum effect, which is simply when you remove an animal, then the next night another animal takes its place.

A 20-year study of urban coyotes by The Ohio State University of the Chicago area in Cook County, Illinois demonstrates the effect of removal of wildlife.

Availability of Resources

The availability of resources is another reason wildlife may be in your neighborhood. Arlington has a very healthy urban ecosystem. Not only do parks, streams, and greenbelts make great habitat, but some backyards do too. Areas underneath sheds, decks, or brush make great homes for many of our wild neighbors. Bird feeders, uncovered trash, vegetable gardens, or pet food that has been left outside provide food for many species.

Nature will Adapt

Research has found that wildlife will adapt when resources are available in a habitat. Litters are bigger, more of the offspring survive, and the numbers return to normal within a year or less. 

Wild Furbearer Conservation and Management in North America (Novak et al, 1987) provides data demonstrating that when raccoons exhibit low reproductive rates, as much as 49% of the population can be trapped out and they will rebound back to their former level by the next breeding season. When raccoons exhibit high reproductive rates (typical with an ongoing trapping program), as much as 59% of the population can be trapped out and the population will replace itself by the next birthing season. A similar scenario has been observed among coyotes and groundhogs.

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Let Wildlife Be Wild!