Habitat Corridor - Prime Examples of Success

Prime Examples of Success

Both the safety of animals and humans can be achieved through the creation of corridors. For example, deer commonly cross roads in order to get to other grazing land. When they are faced with a car coming at them, they freeze; this puts both the deer and the human’s life in danger. In Alberta, Canada, an overpass was constructed to keep animals off of the busy highway; the area is part of a national park, so many different creatures roam the area. The top of the bridge is covered in the native grass of the area so that it blends in better and animals will not know the difference. Gates were also put of on either side of the overpass to help guide animals in the right direction (Semrad 2007).

In Southern California, 15 underpasses and drainage culverts were observed to see how many animals used them as corridors. They proved to be especially effective on wide-ranging species such as carnivores, mule deer, small mammals, and reptiles, even though the corridors were not intended specifically for animals. Researchers also learned that factors such as surrounding habitat, underpass dimensions, and human activity also played a role in how much use they got. From this experiment, much was learned about what would constitute a successful habitat corridor (Dole et al. 2003).

In South Carolina, five remnant areas of land were monitored; one was put in the center and four were surrounding it. Then, a corridor was put between one of the remnants and the center. Butterflies that were placed in the center habitat were two to four times more likely to move to the connected remnant rather than the disconnected ones. Furthermore, male holly plants were placed in the center region, and female holly plants in the connected region increased by 70 percent in seed production compared to those plants in the disconnected region. The most impressive dispersal into the connected region, though, was through bird droppings. Far more plant seeds were dispersed through bird droppings in the corridor-connected patch of land (M. 2002).

There have also been positive effects on the rates of transfer and interbreeding in vole populations. A control population in which voles were confined to their core habitat with no corridor was compared to a treatment population in their core habitat with passages that they could use to move to other regions. Females typically stayed and mated within their founder population, but the rate of transfer through corridors in the males was very high. Researchers are not sure why the females did not move about as much, but it is apparent that the corridor effectively transferred at least some of the species to another location for breeding (Aars 1999).