« Previous  
 Next »

Levin: On Birds And Change

10/22/09 5:55PM By Ted Levin
 MP3   Download MP3 

(HOST) Commentator Ted Levin has been thinking about how studying birds can help us understand changes in the natural world around us.

(LEVIN) There is a consistent theme in nature obvious to anyone who lives in proximity to a rural landscape: nothing ever stays the same; everything changes - from the almost imperceptible changes like a shift in the composition of soil microbes; to thrilling changes like bald eagles returning to Vermont to nest after an absence of more than fifty years. I saw a bald eagle recently on the muddy rim of the Connecticut. The eagle gripped a four-foot long American eel by the head. In thirty-two years I have never seen an eel on the Connecticut River.
    
The distribution and abundance of plants and animals changes over time; in fact, the very nature of species themselves is in flux. Climate and geology run in great cycles that span eons, and without the aid of sophisticated scientific equipment are difficult to sense in a human lifetime. 
   
On the surface, watching birds provides the beauty of color, song, and flight; however, below the surface, watching birds provides a window to the nature of changes, both local and regional. To that end, the Vermont Center for Ecostudies, supported by Vermont's Fish and Wildlife Department, has organized and compiled the state's second Breeding Bird Atlas thanks to the volunteer effort of 350 citizen-scientists, who spent five years inventorying birds from the plains of Lake Champlain to the summit of Mt. Mansfield to the riverine swamps of Vernon. Based on a scale of probabilities, which relies on the interpretation of bird behavior, species were listed as Possible, Probable, or Confirmed breeders. When the results of the second Atlas are compared to the results of the first Atlas, conducted between 1976 and 1981, changes are noted and trends become apparent. 
   
All the data from the second Atlas has been computerized; distribution maps have been generated. And now, with the guidance of the Center's project director, Roz Renfrew, I have the enjoyable task of editing many of the species accounts. And here, with the broad-brush strokes of both climate and landscape changes is some of what I've learned. 

Grassland birds like eastern meadowlark, bobolink, grasshopper and vesper sparrows, as well as upland sandpiper are disappearing as agricultural practices change and abandoned pastures and farmland revert to forest. And woodland birds, wild turkey and common raven for instance, have greatly expanded their ranges in the past quarter century. Hawks whose statewide distribution had been reduced by persistent pesticides commonly sprayed in the middle decades of the 20th century, and thus were rare or absent in the first Atlas, are back. In some cases with gusto. Including Osprey, Cooper's hawk, and peregrine falcon. Merlins have moved into Vermont, perhaps for the first time, and nest in suburbs, cemeteries, village squares, and of course, more remote outposts. And then there's the king of big birds, the bald eagle, like the one I saw clutching the eel that made my day.

Tags

birds
comments powered by Disqus
Supported By
Become an Underwriter | Find an Underwiter