What Is Linking Landscapes?

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1 What Is Linking Landscapes? Viable habitat is critical to the survival of all organisms. As forests, wetlands, open spaces and other habitats are converted to human uses, such as housing, industrial development, roads and agriculture, the remaining natural landscapes become fragmented and isolated. When species lose both their natural habitat and the ability to move between regions to use all of the resources they need to survive, biodiversity is threatened. Creating habitat connections, or linking landscapes, between the remaining open spaces is crucial for the well-being of wildlife that live in these human-fragmented landscapes. The Merrill Linn Conservancy s Linking Landscapes: Natural Areas Network Initiative seeks to establish and maintain habitat connections to allow for animal movement, migration and interbreeding and to enable interbreeding of plants through movements of their seeds and pollen all of which is essential for the survival of species.

2 Conservation biology studies have repeatedly demonstrated the importance of landscape connection to the maintenance of nature s ecological processes. Barrio Colorado Island and How Isolation Impacts Biodiversity Barro Colorado Island (BCI) is a world-class tropical rainforest research site in the middle of the Panama Canal. Scientists from around the world visit this protected island to carry out research on its animal and plant populations. The six-square-mile BCI, once a hilltop within an expansive rainforest ecosystem, was created when Panama s Chagres River was dammed in the early 1900s to form Gatun Lake as part of the Panama Canal. In 1923, BCI was declared a biological reserve and biologists inventoried the species that lived and bred on the island. Soon researchers recorded rapid loss of species and profound changes in the animal population. First to go were the large predators such as the jaguar, puma and harpy eagle. Isolated on the island, these predators could not find sufficient prey to survive. Without these large predators to hold them in check, the populations of mammals, such as pacas, agoutis, peccaries, and coatimundis, skyrocketed. Over the years bird populations plummeted. Initially 208 breeding-bird species were recorded on BCI, but within 85 years of BCI s isolation from the mainland 65 of these species were gone and the numbers of individuals comprising many of the surviving species were dangerously low. To this day, BCI s loss of connection with the mainland rainforest translates to low biodiversity relative to the level of biodiversity at the time of isolation. Landscape connections within an ecosystem have many functions. The facilitation of animal movement, migration, and interbreeding and the interbreeding of plants, through movements of their seeds and pollen, assist in the expansion of these populations. It makes possible the recolonization of small habitat patches by plants or animals from nearby larger patches. It aids the movement of species in the face of climate change and much more. Landscape connections are absolutely crucial for the well-being of all organisms that live in our human-fragmented landscapes. Creating linked landscapes, or ecological connectivity, offers the greatest probability of maintaining biodiversity. Improved linkages can lessen the negative impacts of factors like habitat fragmentation and climate change while increasing nature s resilience to environmental changes.

3 THE LEWISBURG STUDIO THE LEWISBURG STUDIO THE LEWISBURG STUDIO

4 With its Linking Landscapes Initiative, the Linn Conservancy and its affiliate, Buffalo Creek Watershed Alliance (BCWA), are working, not only to preserve and protect valuable lands and waterways, but also to establish and maintain connections within the landscape in order to enhance the resilience of protected areas and to halt the loss of biodiversity. This long-term strategic initiative will examine existing ecological connections among our region s protected areas and then will seek to establish new connections and adjacencies among these sites regardless of whether they are protected by public ownership (e.g., state parks, state forests, game lands), foundation ownership (e.g., Degenstein Turtle Creek Park), agricultural preservation, or Linn Conservancy conservation easements. To carry out its initiative, the Conservancy and BCWA will be working with state, county and local government agencies, foundations, other land trusts, like-minded organizations, businesses, community groups and individuals, who can play an important role by creating habitats in their own backyards with the addition of wildlife-friendly native plants. There are opportunities for everyone in our region to improve habitat connectivity and insure the continued biodiversity of the species that make our area unique. Thoreau and the Loss of Plant Biodiversity Henry David Thoreau is best known to many for his book Walden in which he writes about living simply and alone for two years in a little cabin he built on Walden Pond outside Concord, Massachusetts. But biologists and other scientists find Thoreau s work as a naturalist most compelling. Thoreau laid the groundwork for a study of biodiversity and the effects of landscape fragmentation when he began documenting Concord s wildflower species in 1851 when the area was largely undisturbed. Boston University biology Professor Richard Primack and colleagues surveyed the highly fragmented Concord area 150 years later and found that 27% of the native species recorded by Thoreau were now gone. Another 36% of the species that Thoreau recorded are found today in only one or two populations. Consequently, these latter species are now highly vulnerable to extirpation. Numerous other studies done in a wide variety of habitats and with a multitude of organisms have made the same conclusion that isolated small patches of habitat cannot preserve or maintain biodiversity. The bottom line is that habitat patches require connections to similar habitats and that developing and maintaining landscape connections must be central to conservation efforts. Writing: Diane Donato Design: The Market Street Group

5 CHELSEA SHAFFER