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Bird conservation
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Christmas Bird Count
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Bird Trends
Click on a bird of interest below to go directly to its
section.
Loons
Continentally, several trends stand out within the 98th CBC.
There was a significant number of Pacific or Arctic/Pacific
loons reported in eastern North America during this season.
Several factors could be responsible for this, with the most
obvious perhaps being the weather effects already discussed.
However, winter-plumaged loons can be quite difficult to identify.
As the considerable pool of observers on Christmas Bird Counts
becomes better tuned to the nuances of basic-plumaged loons,
it could be that the smattering of Pacific Loons wintering
along the Atlantic coast of North America are finally being
picked out from runt Common Loons, or distantly-viewed Red-throateds.
A new identification challenge is already on the horizon for
this taxon; separation of winter Pacific Loons from their
Asiatic cousins, the Arctic Loon. Life is never simple in
the world of birdwatching.
TOP
Broad-winged
Hawk
Another species being reported and accepted with increasing
frequency on Christmas Bird Counts is Broad-winged Hawk. This
species should not be in North America during the winter season
at all, with the notable exception of the southern tip of
Florida and the Keys. ID questions quickly arise when immature-plumaged
Broad-wingeds are reported in winter; the very similar appearing
Red-shouldered Hawk is far more likely, and immature birds
in molt can be an especially difficult identification challenge.
However, some of the birds being reported are adult Broad-wingeds,
and particularly in odd seasons like the one leading to the
98th Count reports of this species on counts must be carefully
evaluated.
TOP
Trumpeter
Swan
Trumpeter Swans present an increasing challenge to participants
on CBCs. Trumpeters until recently were restricted to their
well-known western haunts, but this species is now being reintroduced
to its former range in the midwest and east. Introduced Trumpeters
are showing up along the Mississippi, as well as in eastern
Canada and along the mid-Atlantic seaboard. Several of these
introductions appear to be taking hold quite well, and CBC
data are being used to evaluate the status of this species
in central and eastern North America. As of yet Trumpeter
Swan is only a "countable" species in the west,
but very soon it may be established again in other regions,
giving counters three species of swans to haggle over. In
fact, a fourth species, Whooper Swan, may become established
in North America as well -- check out the Newburyport, Massachusetts
count!
TOP
House
Finch
Many studies have been conducted using Christmas Bird Count
data tracking the spread of the House Finch across eastern
North America since its introduction into the greater New
York City area in the mid-1940s. A similar study crying to
be undertaken is the documentation of the spread of Eurasian
Collared-Dove from the southeast across the continent. This
introduced species is being encountered in larger numbers
in the southeast every year, and is extending its range rapidly
both northward and westward. In the 98th Count they were noted
as up in numbers in Georgia/Florida, Alabama/Mississippi,
first record in Arkansas, way up in numbers in Louisiana,
and increasing in Texas. Much of North America may soon have
another dove competing with Mourning Doves at feeders.
TOP
American
Kestrel and Northern Bobwhite
Two species reported upon for the past several years in this
summary and throughout the Regional Summaries as universally
in decline are American Kestrel and Northern Bobwhite. These
two species again were reported throughout North America as
in low or record low numbers. The long-term analysis of Christmas
Bird Count data, well beyond that in the scope of this annual
summary, should be undertaken to document the extent of these
apparent declines. The status of Northern Bobwhite is especially
open to question, as local releases of birds as a game species
may tend to cloud the issue of the status of resident populations.
Along this line, please note Dave Sonneborn’s comments
from Alaska! The Christmas Bird Count may also be tracking
the disappearance of one species from the United States; Smooth-billed
Ani. This species’ stronghold has been south Florida,
but Paul Sykes warns it may be on the way out, for reasons
not understood. As illustrated in Paul’s summary, CBC
data dramatically document the decline of this species, and
may be used to highlight species that should be of management
concern.
TOP
Grasshopper
Sparrow
For the past eleven years we have tracked species of interest
in the Christmas Bird Count in this summary. The table
once again lists these species, starting with our diminutive
skulker, the Grasshopper Sparrow. The number of birds reported
this season was mid-way between sightings in the 96th and
97th Counts; fewer individuals were identified than last season,
but in more count circles and in more regions. This makes
sense given the weather pattern; more birds were probably
dispersed farther north, and the species may have been less
concentrated on its North American wintering grounds. A species
like Grasshopper Sparrow poses a continual enigma to researchers
utilizing data such as Christmas Bird Counts; although presenting
occasional identification questions, and not the easiest bird
to locate outside the breeding season, it is a species of
interest to many field observers, and it is common enough
to be encountered with some frequency. The historical CBC
data now becoming available through BirdSource will shed even
better light on the long-term status of Grasshopper Sparrow
than can be achieved in the year-to-year comparisons included
here.
TOP
Bohemian Waxwing
In this forum we do better with a species such as Bohemian
Waxwing, our next suspect in table
. There was a significant movement of this species during
the 98th Count, though it did not follow the same pattern
as the winter finch flight. Bohemian Waxwings were noted in
unusually low numbers in their core range in Alaska and the
interior of western Canada, but were in high numbers in eastern
Canada, with large flocks appearing all the way to the Atlantic
Coast in the Canadian Maritimes. There was a fair flight into
northern New England, but with a sharp southern cut-off that
restricted the flight to a much smaller region than that seen
in the epic flight of the winter of the 94th Count. Areas
in the northern Rockies also well-clad with large flocks of
Bohemian Waxwings, but very few made it south of Wyoming.
Overall there was a major, but well-defined movement away
from the expected breeding areas of northwestern North America,
producing large numbers of these wandering frugivores in some
regions, but not to the extent of four years ago. Winter irruptive
species are very well tracked by the Christmas Bird Count;
observers are out in force over the entire continent, and
breadth and scope of these annual movements can be compared
and contrasted over time utilizing the data collected.
TOP
Evening
Grosbeak
The remaining three species in table,
Evening Grosbeak, Red Crossbill, and Common Redpoll, illustrate
the varying ways that species respond during superflight years.
Evening Grosbeaks moved early in the flight, and in fact during
the Christmas Bird Count period were tallied in only average
numbers. Several areas, mostly in the midwest or central Rockies,
experienced a paucity of these voracious feeder birds. The
only region with even fair numbers of Evening Grosbeaks reported
was northeastern North America, but even these totals were
far below those of large flight year like the 94th and 96th
Counts. Where did they go? Perhaps Evening Grosbeaks move
southward in concentrated fashion during the fall, then dispersed
into smaller flocks for the winter, resulting in fewer total
birds tallied per count.
TOP
Red
Crossbills
Red Crossbills, when encountered, are seldom found in flocks
approaching the size of Evening Grosbeak herds (table).
Over much of North America it is a treat to encounter this
species at all on a Christmas Bird Count. Therefore the total
of 242 counts in 50 regions encountering a total of over 5500
Red Crossbills is notable, especially when we realize that
this was just the tip of the iceberg. Crossbill numbers (both
Reds and White-wingeds) built throughout the winter, with
some birds dispersing well into the southern lowland regions
of North America, only retreating northward after the end
of February. Interestingly, there were very few Red Crossbills
reported this season in the region where they did undertake
a major irruption during the 97th Count, in the southern Rockies
and the desert southwest. Perhaps they knew to emigrate to
greener pastures. However, clouding the Red Crossbill picture
is a taxonomic enigma: what we currently identify as "Red
Crossbill" may well be several closely-related species,
separable in the field only by bill size and call notes. The
"Type 2" Red Crossbills, the breeders in the southern
Rockies and desert southwest sky islands, probably were not
involved in this year’s superflight.
TOP
Common Redpoll
Then there were the redpolls (table).
Much of the continent was covered by a chipping swarm of Common
Redpolls during the winter season of 1997-1998, and they were
well documented in the 98th Count. Common Redpoll was noted
as being in high or record numbers in the Canadian Maritimes,
Quebec/Ontario, New England, New York, Ohio, Wisconsin, Illinois,
Iowa, the Dakotas, and Montana/Idaho. Over 40,000 were found
in Ontario alone, and they were only missed on one count in
that province. A flock even made its way to Bermuda! Overall,
about one-third of all North American counts encountered Common
Redpolls, in numbers approaching the epic flight of the 94th
Count. It is interesting to note that some sort of irruption
of Common Redpolls happens roughly every other year; we’ll
see what happens in the 100th Count.
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