THE CHANGING SEASONS: OSCILLATIONS 
Spring 2009 was an above-average season 
for western and mid-continental birds in the 
East. Well, at least for passerines: other than 
the above-mentioned geese, single Buff- 
breasted Sandpipers in Illinois and Virginia, a 
Ferruginous Hawk in Iowa, a Prairie Falcon 
in Indiana, a Swainson’s Hawk in Tennessee, 
and a Whooping Crane in Quebec (we could 
add a few more but will leave off the Harris’s 
Hawk in Ontario), it was not an impressive 
spring season for nonpasserine birds east of 
typical range. Regional editors east of the 
hundredth meridian, however, often com- 
mented on western passerines, particularly 
emberizids and cardinalids (including Piran- 
ga tanagers). Steve Dinsmore, writing of the 
spring in Iowa and Missouri, notes that “the 
season [...] had a distinctly western flavor, 
with reports of Western Tanager, Chestnut- 
collared Fongspur, Black-headed Grosbeak, 
and Fazuli Bunting.” Mark Fockwood, Eric 
Carpenter, and Willie Sekula comment on “a 
clear push of western birds eastward that was 
highlighted by much larger-than-average 
numbers for species such as Fark Sparrow, 
Clay-colored Sparrow, Fazuli Bunting, and 
Western Tanager into the eastern half of the 
state.” Joe Grzybowski and Ross Silcock, in 
the Southern Great Plains report, write that 
Table 1 . Reports of Western Tanager in the eastern half of North 
America, spring 2009. Note that Gulf coastal states produced the 
only March records of the species in the East this season. In addi- 
tion to the records below, the Minnesota had five Western Tan- 
agers on unspecified dates. 
Hdrahun, Jefferson, LA 
2-9 Mar 
Niceville, Okaloosa, FL 
9-10 Mar 
Tallahassee, FL 
22-28 Mar & 5 Apr 
Plainfield, Union, NJ 
ll-14Apr 
Putnamville, Putnam, IN 
24-28 Apr 
Juneau, W 
27 Apr 
Omaha, NE 
28-30 Apr 
Roberval, Quebec 
29 Apr-4 May 
McCormick Place, Chicago, IL 
1 May 
Madison, CT 
8 May 
Cherokee, Cherokee, lA 
9-10 May 
Harris Hill, Rainy River, ON 
11-15 May 
Kenora, Kenora, ON 
12 May-4 Jun 
Balmoral, Manitoba 
14-19 May 
Cerro GortJo, lA 
15-17 May 
near Douglas, Manitoba 
18-22 May 
Beverly Shores, Porter, IN 
19 May 
Thunder Bay, ON 
19-20 May 
Waukesha, Wl 
19-21 May 
Dryden, ON 
21 May 
Mississagi Light, Manitoulin, ON 
22 May 
Winnipeg, Manitoba 
23-27 May 
Longlac, Thunder Bay, ON 
2 birds; late May 
“this season will also go down as the year of 
Fazuli Buntings, especially in eastern and 
central Oklahoma” and note higher-than-nor- 
mal numbers of Black-headed Grosbeaks in 
the eastern half of their region; however: 
“there was no eastward shift noted for other 
species — distribution of other western taxa 
seemed more normal.” 
It makes perfect sense to attribute the 
above-average appearances of species such as 
Fazuli Bunting and Western Tanager to “per- 
sistent southwesterly air flow,” as Dinsmore 
does, just as other editors ascribe the appear- 
ance of geese in the Northeast to such winds. 
We do this routinely in the late autumn sea- 
son, when Ash-throated Flycatchers and Cave 
Swallows materialize like clockwork in the 
East after southwesterlies blow from the 
southern Great Plains, so why not in spring? 
It is probably correct to suggest some con- 
nection, and certainly our lead article in this 
issue — which does almost all the heavy lifting 
we might have done here for the month of 
April — gives a very convincing argument for 
the long-distance, over-ocean transportation 
of hundreds of Neotropical migrants, all fly- 
ing downwind on southwesterly winds and 
making landfall far to the north of normal for 
that time of year, as winds at last blew shore- 
ward at the latitude of the Northeast. The 
sorts of fallouts documented by our longtime 
contributor Ian McFaren and his son James 
McFaren in this article are not altogether rare, 
but it is rare that we get such a clear associa- 
tion between, and analysis of, such fallouts 
and weather patterns. (We look forward to 
further publications on this phenomenon by 
James McFaren.) Certainly, this case is ex- 
treme, in a sense: birds flying over open ocean 
with unfavorable winds have far fewer op- 
tions for refuge than birds flying over terres- 
trial environments, which in most cases may 
simply arrest migration when conditions for 
flying prove unfavorable — the longspurs in 
our frontispiece make a good example, as 
does the 26 May fallout of grounded warblers 
on the streets of Grand Forks, North Dakota, 
where 250 Tennessee, 34 Bay-breasted, 32 
Chestnut-sided, 52 Blackpoll, 23 Blackburn- 
ian, and 17 Magnolia Warblers, plus a rare 
Yellow-throated Warbler, foraged in American 
Elm flower litter at the feet of local residents. 
(Folks, that had to be colorful.) 
Try as we may, we do not yet have a clear 
understanding of what conditions might pro- 
duce eastward displacements of western birds 
in spring. Part of the problem is obvious: the 
appearance of “western” birds in the East dur- 
ing spring migration may not or always indi- 
cate long-distance longitudinal displacement 
by winds with a westerly component. Take, 
for instance, the situation with Western Tan- 
agers, one of the examples mentioned in mul- 
tiple regional reports (Table 1). In addition to 
the 24 birds listed in the table, Texas birders 
found at least 13 on the upper and central 
coasts 1 March through 20 May, while Min- 
nesotans and North Dakotans found nine in 
total. And 1 have probably missed a few 
records here and there, though a check of 
eBird did not reveal additional reports of va- 
grants between March and May 2009. First, 
we have to consider the possibility that birds 
found in areas east of past migratory routes 
indicate a gradual eastward expansion in 
breeding range (and thus, potentially, migra- 
tory pathways). Alan Wormington indicates 
that “Western Tanager is now an annual 
spring visitor to northern Ontario, where 
birds invariably appear at feeders” (but: “six 
this spring was rather outlandish”); the 
species has been seen in ten of the past 11 
years in Quebec; and spring and early sum- 
mer records from several parts of Manitoba 
are clearly on the increase. If Western Tan- 
agers are becoming less and less western, then 
the temptation to associate easterly migrants 
with weather patterns should be resisted. 
Many of the birds in Table 1, in fact, in the 
East were noted at bird feeders, including the 
Western Tanager that joined the remarkable 
wintering Scarlet Tanager in Fouisiana. And 
in the southernmost states, some of these 
birds were discovered rather early in the 
spring season, much earlier than typical mi- 
grants. Indeed, some of the birds probably 
never departed the United States, instead win- 
tering — like western hummingbirds and ori- 
oles — in food-rich neighborhoods, with orna- 
mental plantings, occasional emergences of 
insects, and those irresistible bird-feeding sta- 
tions. (In 1981, a generous retiree in Virginia 
Beach, Virginia supplied a wintering Western 
Tanager with cheese grits, scrambled eggs, 
and fruit salad. As a chilly teenager waiting 
for the bird’s appearance, I was tempted to 
help myself to the breakfast bar!) Regional 
editors Veit, Paxton, and Rohrbacher in the 
Hudson-Delaware region comment that a 
Western Tanager in New Jersey 11-14 April 
“seems bizarre for this usual fall vagrant but 
follows closely the occurrence of another in 
Central Park last spring.” But the bird could 
hardly be considered “bizarre” if it had win- 
tered not too far away. Out West, in Southern 
California, Guy McCaskie and Kimball Gar- 
rett probably hit the nail on the head: “We 
long ago ceased presenting 'arrival dates’ for 
374 
NORTH AMERICAN BIRDS 
