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Notes on Eurasian Barn Swallows in Alaska, Including the First Documentation of Successful Breeding in North America

Western Birds 48:197–204, 2017; doi 10.21199/WB48.3.4
BRYCE W. ROBINSON, 615 East Krall St., Boise, Idaho 83712;
LUCAS H. DeCICCO, Department of Ecology and Evolutionary Biology and
Biodiversity Institute, University of Kansas, Lawrence, Kansas 66045
The Barn Swallow (Hirundo rustica) is a widespread and polytypic species compris-
ing six to eight subspecies (see Vaurie 1959, Peters 1960, Cramp 1988, Brown and
Brown 1999, Dickinson and Dekker 2001, Turner 2004, Dor et al. 2010, Dickinson
and Christidis 2014). The New World subspecies (H. r. erythrogaster) breeds over
parts of South America (Grande et al. 2015) and most of North America, north and
west to Alaska (Brown and Brown 1999). In Alaska it is a fairly common or uncom-
mon breeder, respectively, in southeastern and south-central Alaska, and a casual
visitant elsewhere in the state (Gabrielson and Lincoln 1959, Kessel and Gibson 1978,
Gibson and Kessel 1997, Gibson and Withrow 2015). Historically the species bred
more widely in Alaska; however, sometime in the past century its range contracted
substantially (Kessel and Gibson 1994, Gibson and Withrow 2015). Additionally,
two Eurasian subspecies occur as visitants in Alaska. Both differ from erythrogaster
in having whitish rather than rufous underparts (Phillips 1986): H. r. rustica, which
breeds across Europe, the Middle East, and western Asia, and H. r. gutturalis, which
breeds south and east of rustica from Amurland and Ussuriland in the Russian Far
East south to northern China, Korea, and Japan (Turner 2004). There are no previous
confirmed records of the Eurasian taxa breeding in North America. Here we review
and update the status of the two Eurasian taxa in Alaska and document the successful
breeding of a pair of H. r. gutturalis in western Alaska.
On 28 July 2016 we observed an adult white-bellied Barn Swallow in the Nome
Department of Transportation’s utility yard, approximately 4 km northwest of Nome
on the Seward Peninsula, western Alaska. On 5 August at the same location, Robinson
heard calls of begging young that led him to two adult Barn Swallows (Figure 1) attend-
ing four fledglings perched on light fixtures attached to the side of a building (Figure
2). He observed and photographed the pair provisioning the fledglings multiple times
over a 10-minute period, during which the fledglings also made brief foraging flights
to attempt to capture insects themselves. Unfortunately, because of his impending
departing flight out of Nome, further study was not possible.
We identified the two adult Barn Swallows nesting in Nome as H. r. gutturalis
after comparing our photographs of these birds to published descriptions of plumage
variation among the subspecies (e.g., Phillips 1986) and to photographs of specimens
of H. r. erythrogaster, rustica, and gutturalis housed at the American Museum of
Natural History (AMNH), New York, and the University of Alaska Museum (UAM),
Fairbanks. On the basis of photographs of specimens at AMNH, Robinson illustrated
the differences among these taxa (Figure 3), providing a comparison for the birds
at Nome. The Nome breeders best matched the illustrated distillations of gutturalis
(Figure 3C and D) and differed from nominate rustica (Figure 3A and B) in having
a less complete breast band and proportionally shorter tail streamers. They differed
Figure 2. Three of four fledgling Eurasian Barn Swallows (H. r. gutturalis) being
provisioned by an adult on 5 August 2016 near Nome, Alaska. Over 10 minutes, we
observed two adults repeatedly attending the fledglings, which also made flights to
attempt to capture insects themselves.
Photo by Bryce W. Robinson/USFWS
Figure 1. Two adult Eurasian Barn Swallows (H. r. gutturalis) that we observed
provisioning four fledglings near Nome, Alaska, on 5 August 2016. Plumage features
that support our identification of the birds as subspecies gutturalis include short outer
tail feathers (relative to those of nominate rustica), whitish underparts, and broken
breast band (compare Figure 3).
Photos by Bryce W. Robinson/USFWS
also from erythrogaster (Figure 3E and F) in their whitish underparts and more
extensive breast band.
Nominate rustica and H. r. gutturalis have been documented in Alaska by a
combined total of seven specimens (Table 1). Gibson and Withrow (2015) regarded
both taxa as casual visitants in Alaska with rustica substantiated by two specimens,
FMNH (Field Museum of Natural History, Chicago) 174044 and UAM 3781, both
from Utqiag
.vik (Barrow), and gutturalis by three, UAM 2905, UAM 2577, and
UAM 2808, from St. Lawrence I., Old Chevak, and Agattu I., respectively. Two
additional specimens exist: CHAS (Chicago Academy of Sciences) 5254, identified
(on the label) by H. Friedmann as gutturalis, and USNM (U. S. National Museum,
Washington, D.C.) 337966, identified (on the label) by A. R. Phillips (in 1986) as
nominate rustica, although Friedmann (in 1939) had identified it as gutturalis. Photos
show that CHAS 5254 has a thick and complete dark breast band, a characteristic
of rustica, not gutturalis. As for USNM 337966, photos show that its venter is not
whitish, casting doubt on its identification as either rustica or gutturalis. Therefore,
for the time being, this specimen may better be left unidentified to subspecies. The
subspecific identity of the Agattu I. specimen (UAM 2808) has likewise been in flux
(cf. Byrd et al. 1978, Phillips 1986, Gibson and Byrd 2007), and annotations on the
labels make clear the tentative nature of several others.
Variation in the phenotype of Barn Swallows across Asia is complex, and “popula-
tions in Eurasia intergrade” (Turner 2004:665). We are unaware of any treatment
outlining methods for diagnosing (sensu Patten and Unitt 2002) particular subspe-
cies, thus the difficulties in determining the origins of some such Barn Swallows
recorded in Alaska. In one example of the Barn Swallow’s uncertain taxonomy in
east Asia, Vaurie (1954:11) stated, “In H. rustica the status of the populations found
Figure 3. Three subspecies of the Barn Swallow: H. r. rustica (A, male; B, female),
H. r. gutturalis (C, male; D, female), and H. r. erythrogaster (E, male; F, female).
The plumage of the birds that nested near Nome was most similar to C and D with
whitish underparts, relatively short outer tail feathers, and a broken incomplete breast
band. Illustrations are composites based on photos of 18 specimens (six per taxon)
provided by the American Museum of Natural History.
Illustrations by Bryce W. Robinson
in Siberia from about the Yenisei eastward to the coasts of the Sea of Okhotsk and
Kamchatka south to Manchuria and northern Hopeh is not clear … [these popula-
tions are] very variable.” The orange-bellied populations breeding in the Kamchatka
Peninsula and around the Sea of Okhotsk have been considered a subspecies for
which the oldest name is saturata. Dementiev and Gladkov (1968) designated most
of these as erythrogaster but suggested alternatively that they may instead represent
intergradation between gutturalis and the orange-bellied subspecies tytleri (breeds
in central Siberia and northern Mongolia north and northwest of gutturalis). This
view was also expressed by Smirenskiy and Mishchenko (1981; see also Dickinson
and Dekker 2001). Also problematic is how the orange-bellied tytleri or saturata (as
listed by Dickinson and Christidis 2014) may be distinguished from erythrogaster
(e.g., see Ridgway 1904), although they are considered by some sources to have a
more extensive breast band (Turner and Rose 1989, Brown and Brown 1999). Their
described ranges suggest their likelihood of reaching Alaska is at least as great as that
of gutturalis and much more likely than that of nominate rustica (breeds no closer
than the basin of the Yenisei River in central Siberia). Stejneger (1885) reported
tytleri from the Commander Islands. The identification of extralimital birds is clearly
Table 1 Records of Eurasian Barn Swallows in Alaska with Documentation Sufficient
for a Tentative Identification to Subspecies
Subspecies Date Locality; regionaReferenceb
July 1931
spring 1934
.vik (Barrow); N
St. Lawrence Is.; W
CHAS 5254
UAM 2905
rustica 20 June 1934 Utqiag
.vik (Barrow); N FMNH 174044
rusticacspring 1938 St. Lawrence Is.; W USNM 337966
gutturalis 6 July 1973 Old Chevak; W UAM 2577
gutturalis 12 June 1974 Agattu Is.; SW UAM 2808
rustica 22 July 1980 Utqiag
.vik (Barrow); N UAM 3781
rustica 27–29 June 1977 Colville R. Delta; N ML 45473961,
gutturalis 1 May 2005 Anchorage; S-C ML 45441911;
N. Am. Birds 59:480
rustica 18–25 July 2014 St. George Is.; SW ML 47479971
rustica 25 June 2016 St. Paul Is.; SW ML 30601301
gutturalis 5–6 June 2016 St. Lawrence Is.; W ML 30593591,
30593601, 30593611
gutturalis 10 June 2016 Seward Pen.; W ML 30542651
rustica 10 July 2016 Utqiag
.vik (Barrow); N ML 31107141,
31107171, 31107201
gutturalis 28 Jul–5
Aug 2016
Seward Pen.; W This report
aAs outlined by Gibson and Withrow (2015): N, northern; S-C, south-central; SW, southwestern; W, western.
bSpecimens are deposited at the Chicago Academy of Sciences (CHAS); Field Museum of Natural History,
Chicago (FMNH); Univerity of Alaska Museum, Fairbanks (UAM); and U.S. National Museum of Natural
History, Smithsonian Institition, Washington, D.C. (USNM). Photographs are archived at the Macaulay
Library, Cornell University, Ithaca, New York (ML).
cThis specimen’s venter is not entirely white, having some rufous in the wing pits and more laterally on the
flanks, suggesting that its identification as rustica by A. R. Phillips (or as gutturalis by H. Friedmann), is
fraught with uncertainty (e.g., Clancy 1970), background for the following discussion
of photographic and specimen evidence.
Most reports of Eurasian Barn Swallows in Alaska are based on observations of
“white-bellied” birds. We reviewed eight records supported by photos of sufficient
quality (now archived at the Macaulay Library) of Eurasian Barn Swallows in Alaska
from 1977 to 2016 (Table 1). There are additional photo-documented records that
we did not consider because of the photos’ poor quality or because the birds’ plumage
was ambiguous. Of these eight records, we suggest that four from northern Alaska
and from the Pribilof Islands in southwestern Alaska represent rustica and four from
western, southwestern, and south-central Alaska represent gutturalis (Table 1). On
the basis of the previously reviewed specimens and these photographic records,
we suggest that subspecies rustica be considered casual in northern, western, and
southwestern Alaska and that subspecies gutturalis be considered casual in northern,
western (where it has now bred), southwestern, and south-central Alaska.
With “only half a dozen” reports, Kessel (1989:236) regarded the Barn Swallow as
a “very rare spring migrant and early summer visitant” on the Seward Peninsula. In
this area, the North American subspecies erythrogaster appears to be more regular
than either Eurasian taxon. In addition to the nesting in 2016, we were able to find
two records of probable Eurasian birds on the Seward Peninsula: of one “white-bellied”
bird on 13 June 2000 at Teller (North American Birds 54:413, 2000; no photo) and
one on 10 June 2016 at Salmon Lake 50 km inland from Nome (C. Turner and R.
Cimino, in litt., 2016; appeared to be gutturalis from a single photo). We are aware
of just one previous recent nesting record of the species for the Seward Peninsula: a
pair of rusty-bellied birds, presumably erythrogaster, at Solomon, 50 km to the east
of Nome along the Nome–Council road in summer 2008 (North American Birds
62:604, 2008). Late in the 19th century Barn Swallows reported as erythrogaster
were regularly found breeding near the Seward Peninsula at Kotzebue Sound (Grin-
nell 1900; MVZ [Museum of Vertebrate Zoology, University of California, Berkeley]
egg 386), St. Michael (Nelson 1883; MVZ egg 692), and Nulato (Nelson 1887). The
species’ status on the Seward Peninsula at that time is likely to have been similar, e.g.,
Adams (1878) reported nesting at Port Clarence in 1851 (see also McGregor 1902).
Barn Swallows are known for nesting on artificial structures, in some areas exclu-
sively (e.g., Isleib and Kessel 1973, Heinl and Piston 2009). This predilection has
allowed the species to breed elsewhere in peripheral, coastal locations in northern
and western Alaska at Cape Sabine (Childs and Maher 1960), Icy Cape (Lehnhausen
and Quinlan 1981), Utqiag
.vik (Bailey 1948), and the outer Yukon–Kuskokwim delta
(Walkinshaw and Stophlet 1949; see also Harris 1967). The subspecific affinities of
these birds have not always been addressed, but a specimen collected near the Cape
Sabine nest is listed as erythrogaster (MVZ 140241) and Bailey (1948) discussed the
second-hand report at Utqiag
.vik by Charles Brower under erythrogaster.
The breeding of Barn Swallows near Nome in 2016, the first confirmed in North
America by any subspecies besides H. r. erythrogaster, is notable given the status of
Eurasian Barn Swallows in Alaska. It is also of interest that this event took place in
the same year as the first recorded Alaska breeding of the Eastern Phoebe (Sayornis
phoebe), 18.5 km from the location of the Barn Swallow nest (Robinson et al. 2017).
For species largely dependent on artificial structures for nesting, such as the Eastern
Phoebe and the Barn Swallow, further such development may facilitate additional
extralimital breeding. This may lead to changes in the species’ distribution (Okes et al.
2008, Livezy 2009), especially if compounded by the effects of climate change, which
have been correlated with changes in birds’ distributions in Europe (Massimino et al.
2015) and elsewhere. To expand our understanding of the human influence on the
natural world, it is important to document extralimital breeding through publications
such as this and other forms of contributions such as data entered at www.eBird.
org. Further diligence in documenting extralimital breeding by the Barn Swallow in
places such as Alaska may provide a foundation for understanding shifts in breeding
distributions and provide insights into historical changes.
We thank Pavel Tomkovich, Georgy Semenov, Elizabeth Scordato, and Rebecca
Safran for their comments on the subspecific identification of the Nome birds. We
thank Paul Sweet at the American Museum of Natural History for providing photo-
graphs of the specimens used for identification and the creation of Figure 3. Chris
Milensky (U. S. National Museum, Smithsonian Institution), Mary Hennen (Field
Museum of Natural History), Mark B. Robbins (University of Kansas), and Dawn
Roberts (Chicago Academy of Sciences) provided photographs of Alaska specimens
at their institutions. We thank Theodore G. Tobish Jr. and Scott Schuette for help with
details of some Alaska Barn Swallow records, and the following photographers on
whose material part of this note is based: Christian Hagenlocher, Jim W. Helmericks,
Theodore G. Tobish Jr., Wyatt Egelhoff, Stephan Lorenz, Aaron J. Lang, and Craig
Turner. Reviews of the manuscript by Daniel R. Ruthrauff, Daniel D. Gibson, Steven
C. Heinl, and Jack J. Withrow are greatly appreciated. Finally, we thank James A.
Johnson and the U. S. Fish and Wildlife Service for providing the opportunity for
our time in Nome, without which these observations would not have been made.
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Accepted 20 July 2017
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