Species or ecosystems that require specific environmental conditions to survive are likely to be threatened by pressures like land clearing, drought or increasing temperatures. If these species and ecosystems have nowhere to go they face extinction. However, if they can move along a habitat corridor to refuge areas (also called refugia) that offer more favourable environmental conditions and reliable food sources, their chances of survival are greatly increased.
Historically, global climatic cycles have driven the contraction of various species and ecosystems (such as rainforest species) into refugia. As a result, these locations often contain relict populations of species that may have once been widespread. The Wollemi Pine is a world-famous example of this. As climatic conditions changed long ago, the Wollemi Pine’s habitat was restricted to a small number of patches of warm temperate rainforest within Wollemi National Park in the Great Eastern Ranges corridor. Before it was discovered in 1994, it was known only from fossils, and was thought to have been extinct for two million years.
In modern times, species that have recently decreased in range due to pressures such as habitat loss or invasive species often rely on refugia to survive in the long term. As climatic conditions change in the future, some species may migrate to refuge areas outside of their current range.
Refugia within the GER corridor
The vast dissected tablelands and escarpments of the Great Eastern Ranges contain a much wider variety of landscapes, due to variations in slopes, temperature, rainfall, shelter, topography and soil types, than other areas in Australia. This means that they provide a great range of refuge areas for animals and plants. For example, the ruggedness of the terrain along the Great Escarpment creates many microhabitats, including cliff faces, deep valleys, gorges, exposed ridgelines and waterfalls, offering protection for species and ecosystems from natural and man-made threats.
By protecting potential new and current refuge areas, and linking them with other habitats, GER is maximising the potential for native species to survive climate change and other significant pressures.