THE CHANGING SEASONS: CORNUCOPIA 
Figure 10. This juvenile Long-tailed Jaeger patrolled waters conveniently close to the dam 
at McIntosh Reservoir in Longmont, Boulder County, Colorado on 7 September 2008. It 
was also seen on the bike path atop the dam, apparently hunting grasshoppers, a behav- 
ior not typical of Parasitic or Pomarine. Photograph by kott Severs. 
October 1977 in Missouri (Easterla 2008) that 
predates the recent large expansion in the 
population of southwestern Caves and their 
now-annual late-autumn incursions into the 
East. It also pre-dates the known, limited col- 
onization of south Elorida by Caribbean birds 
(nominate /ulva). There are two earlier speci- 
mens of Caribbean Cave Swallows from Nova 
Scotia, in June 1968 and May 1971. More re- 
cent spring reports from New York, New Jer- 
sey, Virginia, and North Carolina have not 
been assigned to subspecies. 
Before the late-autumn occurrence of Cave 
Swallows became a regular event- — ^and com- 
mon knowledge — during the mid-1990s, 
there had been several sight reports of Cliff 
Swallows in November. There are, in fact, a 
number of documented records of Cliffs dur- 
ing that month since the mid-1990s, but bow 
many of those earlier birds were seen by ob- 
servers who did not even consider Cave Swal- 
low? These reports should now be considered 
as involving only “Petrochelidon species.” 
There also have been reports over the years of 
Cliff Swallows during November and Decem- 
ber in the West that were not critically exam- 
ined at the time and should be demoted to the 
level of genus as well. 
Inland jaegers 
This is another case in which conventional 
wisdom appears to have been at least partly 
incorrect. But unlike the situation with win- 
tering Semipalmated Sandpipers, it has yet to 
be fully corrected. Many observers probably 
believe that, overall, the most expected fall 
jaeger inland is Parasitic. But during the past 
30 years or so, this has been shown to be 
partly in error. Parasitic is typically the most 
numerous jaeger in fall on the largest inland 
water bodies: the Great Lakes, Great Salt 
Lake, American Ealls Reservoir, Lake Mead, 
Lake Havasu, Salton Sea, 
Lake Tahoe, etc. But at 
smaller lakes, sewage 
ponds, glorified puddles, or 
where there is no water at 
all, then Parasitic may well 
be the least likely of the 
three species to occur! At a 
small pond or other strange 
place for a jaeger. Long- 
tailed, followed by Poma- 
rine, are probably the most 
likely species. Also, al- 
though Parasitics begin to 
appear by late August, 
Long-taileds peak during 
August and early September 
(Ligure 10), which increases the odds that 
this species may be involved early in the sea- 
son. In late fall, Pomarines become more 
likely in late October and November, where- 
as Parasitic numbers — while still holding 
on — decline, thus improving the odds that an 
inland jaeger in late autumn and especially 
early winter is, in fact, a Pomarine. Some in- 
land states (e.g., Colorado) have begun to re- 
assess all of their jaeger records. 
Changes in some peripheral (and 
some introduced) populations 
Sometimes we birders take for granted what 
look to be safely established populations. But 
some may have a reversal of fortune and dis- 
appear — sometimes quite rapidly. Such 
changes are particularly evident in peripheral 
and introduced populations — Crested Myna 
in Vancouver, British Columbia, for example. 
Why has the introduced population of Spot- 
ted Doves — at one point having spread over 
several decades in southern California from 
Los Angeles west to Santa Barbara County 
and north to Bakersfield, south to northern 
San Diego (plus a few in northern Baja Cali- 
fornia), and east almost to the Salton Sea — re- 
cently shown a rapid contraction in its range 
to the point that it is almost totally gone? This 
decline largely pre-dates the appearance of 
Eurasian Collared-Doves, which are still ab- 
sent from much of Spotted Dove’s former Cal- 
ifornia range. What effect has the recent in- 
crease in the numbers of nesting Cooper’s 
Hawks in residential areas had? Or nest pre- 
dation by the increasing numbers of intro- 
duced squirrels in some areas? Disease is one 
fairly likely explanation. House Sparrow 
numbers seem to be on the decline in a num- 
ber of regions. Even the Christmas Bird 
Count trends for European Starling seem to 
be down where Lehman currently lives in San 
Diego. Maybe there’s hope yet! Could the 
same happen one day with Eurasian Collared- 
Doves? It doesn't seem likely (New 
Brunswick recorded its first this season, one 
was in Quebec, and it appears to be spreading 
in Mexico), but we shouldn’t make assump- 
tions, either. 
As for a non-introduced colonizing species, 
Shiny Cowbird numbers in the southeastern 
United States peaked around the early 1990s. 
But they have declined substantially since 
then, although we continued to hear many a 
birder talk about the “expanding Shiny Cow- 
bird population” for another decade. Some- 
times birders are slow to recognize these re- 
versals in fortune. Black-capped Gnatcatchers 
are currently colonizing southeastern Arizona, 
but we would rate as 50-50 the chances that 
there are still many pairs there 20 years from 
now, versus the chances that they disappear, 
hollowing a surge in the autumn and winter 
numbers of Ruddy Ground-Doves throughout 
the Southwest beginning in the mid-1980s — 
and the subsequent localized permanent resi- 
dent status and several nesting records in both 
California and Arizona — their numbers have 
declined in most areas during the past several 
years, particularly in California, although the 
autumn of 2008 saw a slight up-tick in Ari- 
zona, Such are the pulses and contractions in- 
herent in many pioneering species. Numbers 
of vagrant individuals may also wax and wane 
substantially across the years. Will the recent 
surge in the numbers of late-autumn Cave 
Swallows and Ash-throated Llycatchers in the 
East be maintained? Why was there a notable 
influx of vagrant Worm-eating Warblers in 
late 2008 to New Mexico, Arizona, and Cali- 
fornia? Weather patterns? A bumper crop of 
young birds raised the previous summer? Sin- 
gle-year and even multiple-year surges in the 
number of vagrant Yellow-throated, Kentucky, 
and Hooded Warblers occurred in California 
during the past several decades, but they did 
not persist. There are many such examples 
from throughout North America. 
Rarities 
Although a quick browsing of all the bold- 
faced species in the regional reports will pro- 
vide a good overview of the rarest vagrants, 
the highlights below stand out as being partic- 
ularly interesting, some even mind-boggling. 
A compilation of most, though not all, first 
state and provincial records included the first 
United States record of Sinaloa Wren in Ari- 
zona (although the species is known to nest 
less than 160 kilometers south of the border), 
Wandering Albatross off both Oregon and 
VOLUME 63 (2009) • NUMBER 1 
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