The success of ecological corridors depends to a large extent on how well they are managed after they are designed. Credit: Félix Mathieu-Bégin
In recent years, researchers and land managers increasingly have turned their attention toward ecological corridors and landscape connectivity for the benefits they provide to the overall ecosystem. When an ecological corridor helps connect habitats, it sets the stage for many important ecological processes such as genetic flow, dispersal, seasonal migrations, and habitat shifts in response to climate change. However, as the human population continues to grow, so do demands for new development and infrastructure. This leads to urbanization of lands that were once wild, and the fragmentation of the surrounding habitats that remain.
A recent literature review provides extensive, detailed guidance for managing successful ecological corridors that are in close proximity to human populated areas. The management recommendations focus on conserving and enhancing the movement of individuals and their genes, with the goal of making corridors more effective in protecting and enhancing both abiotic and biotic flows.
The recommendations highlight best practices for managing corridors across four themes: 1) man made barriers crossing corridors (ie., highways) and how to mitigate them; 2) managing water and riparian areas; 3) managing urban, suburban, and industrial areas in or near corridors; and 4) managing agricultural areas in or near corridors.
Man made linear barriers crossing corridors (roads, canals, etc.)
An outstanding issue found across ecological corridors when linear barriers are present is the fragmentation of habitat, increased road mortality, and wildlife avoidance in general of these man made structures. Suggested ways to mitigate these issues include reduced speed limits, seasonal road closures, raised road beds, and crossing structures, which are meant to funnel wildlife to a safe point of passage between good habitat. Additional practices include minimized artificial lighting, alternative water sources, and wildlife-friendly fencing.
Streams and riparian zones in corridors
Riparian areas are hot spots for wildlife movement, and these zones are integral for creating ecological corridors. Restoration and conservation of native ecosystems within these areas can be promoted by excluding invasive plants, livestock, and other non native grazers, while enforcing policies like the Clean Water Act and restricting mining in close proximity to promote riparian health. Buffers surrounding riparian areas can help support important habitat within the corridor.
Credit: Google Earth
Urban, suburban, and industrial development in corridors
Even in areas where densities are as low as low as one dwelling per 40-50 acres, there are measurable impacts to connectivity. The term “synurbanization” refers to the process where wildlife becomes used to human presence and activity, in turn altering their own behaviors (ex. when predators utilize garbage as a food source and population numbers rise as a result). Stewardship is a primary way to mitigate issues such as these, such as encouraging smaller dwelling footprints and roadwork to minimize impacts and disturbance to the environment in the midst of urban sprawl.
Agricultural development in corridors
Agricultural practices and development can impact ecological connectivity by way of fencing, altered fire regimes, or contaminated water sources via runoff. One main recommendation is to provide education on wildlife and environmentally friendly practices like no till farming, responsible pesticide use, and programs within the U.S. Farm Bill, while also promoting buffer zones to riparian areas.
Overall, it’s safe to say that less is more in the context of human activity within or in close proximity to an ecological corridor. The recommendations outlined are just a few ways in which we can mitigate human interference within ecological corridors.
Resources
Gregory, A., Spence, E., Beier, P. and Garding, E. 2021. Toward best management practices for ecological corridors. Land 10(2): 140.
Connectivity metrics for conservation planning and monitoring (May 2021)
