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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123. No. 4. December 2011 
calyces of this species in lieu of a water supply 
(Fosberg 1959:7). This behavior would be ex¬ 
pected of Rattus exulans, which had centuries to 
adapt to conditions on Wake Island, rather than a 
commensal such as black rats ( R. rattus). 
If rats of European origin (/?. rattus or Norway 
rat, R. norvegicus) got onto Wake Island, this 
would have occurred during or after World War II 
and their presence on the island has been claimed 
repeatedly. The first biologist to assess Wake alter 
the war was A. M. Bailey, who was ashore in mid- 
May 1949. He was the first to report the extinction 
of the Wake Island Rail and wrote that rats “or 
possibly die starving Japanese troops themselves, 
may have exterminated them” (Bailey 1951a: 
36). He further stated that during “the Japanese 
occupation of Wake in WW2, Rattus rattus was 
introduced with devastating eflects on the bird- 
life....As these rats were present after the war, 
their import must have occurred during Japanese 
times.” Bailey may have been proceeding on the 
assumption that the situation paralleled that on 
Midway Island, which he had also visited, and 
where Rattus rattus introduced during WW II did 
exterminate the healthy introduced population of 
Laysan Rail (Olson 1999b), His identification of 
the Wake Island rats may be doubted, however, as 
he does not mention R. exulans. 
Atkinson (1985:40) attributed R. exulans to 
Wake on the basis of Peak's (1848) report and 
inferred the introduction of R. rattus in the period 
1923-1951 from Bryan (1943 [sic = 1942]). 
Fosberg (1959), and King (1973). Bryan, howev¬ 
er, makes no mention of anything that could be 
interpreted as R. rattus but only what is clearly R. 
exulans. It is not at all clear upon what King 
(1973:101) based his statement that on Wake 
Island: “Feral cats [Felix cams\. black and 
Polynesian rats occur on all three islets.” Fosberg 
(1959:7) encountered only a single rat in 1953— 
“a large blackish one,” hut his informant Schultz 
considered there were four kinds of rats on Wake 
Island. Bryan (1959:8) in evaluating that assess¬ 
ment stated that all available specimens of rats 
from Wake were R. exulans and that a “series of 
skins and skulls collected to represent the rat 
populations living on the island would be very 
desirable to settle this question.” 
Bryan was correct that all available specimens 
of rats from Wake have been identified as R. 
exulans. including those from the 1923 Tanager 
expedition (USNM. BBM) and all those obtained 
by Kenler and other Pan Am employees in 1935 
and 1936 (BBM). Trapping that has occurred 
since cat eradication programs began in 1996 
confirmed that the only rats on Wake Island were 
R. exulans until the Asian ship rat (R. tanezumi) 
was trapped on the island in 2007. That species 
is believed to have “arrived during the mid¬ 
sixties with Vietnamese refugees” (Rauzon el al. 
2008a: 13) 
It is possible that either of the widespread 
European commensal species of rats may have 
been introduced to Wake Island and were 
subsequently exterminated by cats, but this would 
almost have to have been in the years after the war 
and it seems unlikely because both R. rattus and 
R. norvegicus are larger, more aggressive species 
that usually supplant and even prey on R. exulans 
(Harper and Vcitch 2006). Therefore, given the 
long period of co-existence of the Wake Island 
Rail with R. exulans prior to the war. we do not 
believe that rat predation was a factor in the 
extinction of Gallirallus wakensis. 
EXTINCTION 
The rail was such an unusual and conspicuous 
element on Wake that it did not escape mention in 
accounts of military officers on the island prior to 
the war. Devereux (1947:22-23), the commander 
of the U.S. Marines on Wake Island, wrote: 
“there was one weird bird I believe is peculiar to 
Wake. It was the flightless rail, which looked to 
me like a tiny cousin of the New Zealand kiwi. I 
do not know how he ever got to Wake because he 
can’t fly.” Bayler (1943:21), another officer 
under Devereux. mentions that: “I studied the 
little red-eyed "peewee’ as it hopped about. The 
peewee is a flightless bird, certainly a strange 
species to find fooling around an airfield. It is just 
a fluffy ball of feathers with no wings and no tail; 
the size of a robin, it is indigenous to Australia, 
and we used to speculate on how peewees could 
ever have come to distant Wake Island." The odd 
belief that the rail came from Australia goes back 
at least to 1935, as Grooch (1936:115-116) also 
alludes to an Australian origin. Bayler’s descrip¬ 
tion of the rail is clearly the basis for the nearly 
identical characterization in Schultz (1978:114). 
Cunningham (1961:40), who was the Navy 
commander on the island contemporary' with 
Devereux, also noted “a species of flightless rail 
no larger than a newborn chick.” Being flightless 
(and, as so often with flightless birds mentioned 
by nonscientific writers, described as “wing¬ 
less”), the rail may have evoked some association 
