Each month we feature one of the 97 IBAs (Important Bird Area) in North Carolina. This month our team from the mountains is showcasing the Highlands Plateau IBA‘s amazing bird diversity. This post is written by Audubon North Carolina’s Curtis Smalling.
The Highlands Plateau is well known for its waterfalls and for its rainfall that keeps those waterfalls running full. With an average annual rainfall of over 60 inches, the Plateau is one of a handful of sites in the US that qualify as a temperate rainforest. Couple that with very high relief topography created by huge granitic monadnocks or steep sheer cliffs projecting out of the mountains, and the waterfalls just have to happen! Many of these are famous, like Bridal Veil (to drive your car under!) or Dry Falls (used in the film Last of the Mohicans) and hundreds of others named and un-named.
This amount of water and cliff faces has connections to the bird diversity of the Plateau as well. The state endangered Peregrine Falcon nests on cliffs like Whiteside Mountain every year. Migrant waterfowl and shorebirds take advantage of the ample creeks, ponds, and lakes, and even some songbirds depend on these watercourses and high humidity.
Riparian birds are those that live along river and creek corridors. Yellow Warbler, Acadian Flycatcher, and Louisiana Waterthrush all live right along stream edges and riparian zones filled with alders and willows or shaded by rhododendron. One special warbler species takes advantage of the high rainfall and humidity in the Plateau to take its riparian ways into the forests.
The lovely Northern Parula is a tiny warbler that is found throughout North Carolina and is usually a pretty strictly riparian bird. This is caused by the bird’s need for filamentous lichen or Spanish moss for nesting. The female Parula builds a suspended nest like a small Baltimore Oriole, usually out over the edge of the water. Often they are limited to riparian zones because the lichen they use (often Usnea sp. Or Old Man Beard Lichen in the mountains) needs high humidity to thrive. In the Highlands Plateau, enough moisture exists that the birds are often found far from water courses in interior forests, yards, and other locations not typically thought of for this species. Often it is hard to show people how water and water quality directly impacts birds, but the tiny Northern Parula helps us understand the connections between water and how birds (and we) live our lives connected to the water cycle.
