What are the biggest threats to the plants and animals within the preserves?
The two greatest threats to the preserve system are invasion from non-native plant species and unauthorized human activities. For example, pampas grass, a common ornamental plant in backyards, can invade natural stream courses and choke out native species that provide habitat for sensitive bird species. This grass spreads quickly and is very difficult and costly to remove. Unauthorized human activities include off-road vehicle use in areas not designated for this activity, resulting in denuded areas, massive erosion, and sedimentation into stream channels. There are many other things that harm native plants, wildlife or habitats. Please see the previous question/answer for more information.
