Loon Magic/Loon Magic - Wayzata Technology (8011) (1993).iso/mac/text/12winter.b

Text File | 1993-07-26 | 4KB | 62 lines

** WINTER VACATION **

   While the highest concentrations of wintering common loons on the
East coast are found off the North Carolina, Virginia and Maryland
coasts, loons can be found in almost all coastal waters from Maine to
Texas. T.|A. Imhof, a University of Alabama researcher, estimated the
wintering population at over 10,000 in an area from the mouth of
the Mississippi to St. Mark's, Florida.

   On the West coast, where the loon populations from Alaska and
western Canada winter, the estimates are much higher.
Approximately 12,000 loons of three species (common, red-throated
and Pacific loons) spend the winter off the Washington coast,
according to Kelly McAllister of Washington's Non-Game Office. Bill
Haight, an Oregon Non-Game official, termed loons "abundant" in the
coastal estuaries of that state. Loons of all four species winter along
California's 800-mile coast and John Gustafson of the California Non-
Game Department receives reports of common loons wintering on
inland lakes and reservoirs of the state.

   A survey completed in the spring of 1984 added considerably to
our knowledge of winter loon movements. Coordinated by Judy
McIntyre, the survey indicated a northward movement of loons
along the Atlantic coast during the winter. In January and February,
the greatest concentrations of loons were found off the coast of South
Carolina. In March, the largest groups were observed off the New
Jersey coast. In April, the concentrations moved up to the
Massachusetts and New Hampshire shores. Both north-south and
inshore-offshore movements were noted along the west coast of
Florida, normally an area of substantial loon numbers. On the Texas
coast, loons were seen in modest numbers in January and February
but by March a pre-migration buildup had occurred.

   It is impossible to know at this time if loons from a given nesting
region travel to a specific wintering site. There would be an adaptive
survival value for loons from geographically distinct populations to
spread out all over the coast. The potential for a single catastrophe
involving disease, pollution or a violent storm to affect an entire
population would be reduced. We do know that winter is a time of
great stress for the loons and it is on the coastal waters that natural
selection does its work. McIntyre terms winter mortality
"considerable." Of nine loons she banded between 1970 and 1973,
three died during their first coastal winter.

   Malcolm Simons, Coordinator of the Atlantic Beached Bird Survey
which monitors bird mortality along the U.S. coasts from northern
Massachusetts to Texas, has termed loon mortality in winter "out of
proportion to its population throughout its coastal ranges." Started in
1975, the Beached Bird Survey utilized volunteers to walk stretches
of coast tallying the dead seabirds they encountered. During the first
four years of the survey, loon mortality was low but, according to
Simons, it increased steadily until the major loon die-off in 1983
when loons accounted for over seventy percent of all the birds found.
While Simons cites severe weather as the greatest cause of seabird
mortality, he does not ignore pollution, especially oil spills. Looking
at all the survey records, he estimates that about seven percent of all
loons found were oiled. The 1983 sinking of the Marine Electric off
the Florida coast resulted in thirty-two loon deaths and an additional
134 oiled loons required assistance.

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