Paul's observations are very interesting and emphasize a point that I think we tend to overlook in our concern for birds that arises understandably from all the pressures they face in a world heavily populated by humans. As hard as it is to watch weather that seems likely to cause mortality (remember last spring's woodcocks), death in winter is a very normal part of the annual cycle. Birds reach their annual population peak in late summer and early fall, right after breeding has been completed. Then it's basically a war of attrition (predators, disease, weather, food shortages, man-made hazards) to make it to the start of the next breeding season, when things will have dropped to their annual low ebb.
I don't point this out to minimize the human-caused problems of which we're all aware. But it's good to bear in mind that birds normally take some incredible natural hits, hits our continent (so far) has been able to absorb. One of the most famous (familar I'm sure to some of you) is the March 1904 destruction of Lapland Longspurs by an ice storm in Minnesota. Accounts of the day put the death toll at millions. According to an article in The Auk, Vol XXIV No. 4 Oct. 1907, a grid system estimate placed the number dead on the ice surface of just 2 lakes at 750,000!
There are also accounts in the Wilson Bulletin of large weather-related longspur die-offs in Nebraska on two dates in February 1922, although no numbers are give.
Greg Hanisek
Paul's observations are very interesting and emphasize a point that I think we tend to overlook in our concern for birds that arises understandably from all the pressures they face in a world heavily populated by humans. As hard as it is to watch weather that seems likely to cause mortality (remember last spring's woodcocks), death in winter is a very normal part of the annual cycle. Birds reach their annual population peak in late summer and early fall, right after breeding has been completed. Then it's basically a war of attrition (predators, disease, weather, food shortages, man-made hazards) to make it to the start of the next breeding season, when things will have dropped to their annual low ebb.
I don't point this out to minimize the human-caused problems of which we're all aware. But it's good to bear in mind that birds normally take some incredible natural hits, hits our continent (so far) has been able to absorb. One of the most famous (familar I'm sure to some of you) is the March 1904 destruction of Lapland Longspurs by an ice storm in Minnesota. Accounts of the day put the death toll at millions. According to an article in The Auk, Vol XXIV No. 4 Oct. 1907, a grid system estimate placed the number dead on the ice surface of just 2 lakes at 750,000!
There are also accounts in the Wilson Bulletin of large weather-related longspur die-offs in Nebraska on two dates in February 1922, although no numbers are give.
Greg Hanisek
