Recently，asmallgroupofbirdwatchersspentthreeweeksaroundMountVernon，thehomeofthefirstpresidentoftheUnitedStates，GeorgeWashington．TheywerebusycountingwildbirdsonMountVernon'swetlands，southofWashington，D．C．

　　Recently，a small group of birdwatchers spent three weeks around Mount Vernon，the home of the first president of the United States，George Washington．They were busy counting wild birds on Mount Vernon's wetlands，south of Washington，D．C．They began in the middle of December and worked until the beginning of January．

　　The Audubon Society's first"Christmas Bird Count"took place 115years ago in 1900．At that time，a man named Frank Chapman suggested a new Christmas tradition--that people count birds instead of shooting them around the holiday．

　　Birds are one of the surest indicators--or barometers--of the health of the ecology．Last year，the bird count recorded over 66million birds of 2，403different species．

　　Gary Langham is chief scientist with the National Audubon Society．

　　"The Audubon climate report says that half the birds in North America--314out of 588species--are seriously threatened by climate change．The impacts sort of cut across all birds，all sizes，all kinds，all places"．Information from the bird counts has shown that birds are staying farther north during the winter months because of warmer weather．Birdwatcher Jaime Reidy has noted the difference close to Washington，in the state of Virginia．"You get to see them at odd times of the year，a little earlier，staying a little later．"

　　Gary Langham says other conditions are affecting bird populations．"You can imagine the birds that live along the beach or along the rocky shore line as sea levels are rising around the world． That is impacting them，you know，doubly so．"David Yarnold is president of the Audubon Society．In his words，"Christmas Bird Count data is becoming important not only in documenting current climate change，but in predicting the future effects of climate change on North American bird populations．If we know what to expect，we can start taking actions now to do something about it．"

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