Why is Wildlife Connectivity So Important?

Mountain lions have one of the most extensive ranges of any land mammal. Territory size ranges from 10 to 150 square miles, but this is becoming increasingly more difficult because of urban sprawl. These cats are found within the park, but they need open passages to migrate to other wildlife areas.

NPS Photo

Wildlife "corridors" are areas that animals can pass through safely between the protected habitats where they can live, eat, drink, and reproduce. At Saguaro National Park, this connectivity is crucial for large animals such as bears, mountain lions, and bighorn that need areas that are larger than the park to survive.

Habitat connectivity is also important for smaller animals, such as kit foxes, badgers, and even reptiles, that tend to need specialized habitats within a protected area. Their populations are too small to be sustained over long periods of time because they need an influx of immigrants, and their young need to be able to leave to find mates.

Unfortunately, structures such as fences, roads, urban and agricultural developments can inhibit habitat connectivity and be major barriers to all kinds of wildlife. These landscape modifications decrease habitat area and reduce diversity simply by shrinking areas in which animals using the habitat can live (MacAuthur and Wilson 1967). Without proper planning, these barriers can constrain wildlife movement and lead to fragmented habitats.

Habitat fragmentation occurs when animal migration is limited, which disrupts their ability to find food, shelter, and mates. Over time populations get isolated from one another and are more vulnerable to diseases, inbreeding and reproductive problems, reducing their resilience to stress and lowering their chance of survival (Wilcox 1985). Some species may even go locally extinct, an event called extirpation.

Extirpation occurs when an animal ceases to exisit in a particular area but continues to exist elsewhere. For instance, we can no longer find grizzly bears, porcupines, jaguars, Mexican gray wolves, and bighorn sheep at Saguaro National Park due to their local extinction. The loss of species is not only bad for the animals themselves, and for the people who enjoy seeing them, but can have huge detrimental effects on the entire desert ecosystem.

By removing wildlife barriers, we can improve habitat connectivity, a key aspect for sustaining biodiversity inside the park because many species require resources that extend beyond park boundaries. For more information on connecting Saguaro National Park to its surrounding landscapes check out this resource brief on connectivity.