Olson and Rauzon • WAKE ISLAND RAIL 
683 
involved. With the onset of human occupation of 
the island, vehicular traffic became a source of 
mortality. Lyons’ only adult specimen was a 
female found on Wake Island proper that had been 
run over by a truck, which provoked the very 
curious comment that the “wing bone [presum¬ 
ably the humerus, was] only about '/ah as 
resistant to fracture as leg bones” (Lyons 1939. 
25 Oct). Scientific collecting accounted for 66 
additional specimens over a period of nearly 
50 years with the 46 removed in 1923 having 
clearly had no influence on population size as 
evidenced bv the abundance of the species in the 
late 1930s. 
Possible Mortality from Inundation. —Begin¬ 
ning with the L.S. Exploring Expedition (1841), 
visitors have remarked on the evidence of the 
effects of high seas on Wake Atoll. “From 
appearances, the island must be at times sub¬ 
merged, or the sea makes a complete breach over 
it: the appearance of the coral blocks and of all the 
vegetation leads to this conclusion, for they have a 
very decided inclination to the eastward, showing 
also that the violent winds or rush of tile water, 
when the island is covered, are from the 
westward” Wilkes (1844:285). The expedition’s 
naturalist, Titian Peale, also noted that “the only 
remarkable part in the formation of this island is 
the enormous blocks of coral which have been 
thrown up by the violence of the sea" (Pocsch 
1961:199). Wetmore noted on Wake Island in 
1923 that "huge blocks of a consolidated 
conglomerate of coral and coral sand have been 
thrown up at intervals, some of them from eight to 
fifteen feet in diameter” (Olson J996:105). In 
exploring the atoll in 1935. Grooch (1936:92-93) 
found that Wilkes Island “was no place to build an 
air base because it showed plain evidence of having 
been underwater. |Thcrc were) logs in the center of 
the island that could only have been washed up by 
the sea. In many places driftwood was lodged in the 
trees overhead.” Yet it “was at once apparent that 
Peale Island was a different place altogether from 
Wilkes Island. There were no rocks and the soil 
was a rich brown loam. There were fair sized trees 
and many vines, and no evidence whatever that the 
island had been under water.” 
Them is little doubt that inundations by the sea 
had an elfect on mortality of the rails. Wetmore 
noted that Wilkes had apparently home the “full 
brunt of the typhoon that swept the atoll. Large trees 
Were entirely destroyed’' and ‘ ‘strangely enough no 
rail have been found in Wilkes Island though the 
birds are common on Wake Island across a narrow 
channel (Olson 1996:108). Flightless rails swept 
out to sea in a storm would most likely have 
drowned or been eaten by predatory fish. 
Possible Mortality from Predators. —Wetmore 
(1970:4) accurately summarized the potential for 
predation on the rail: “The rat mentioned and a 
hermit crab that swanned on the island would 
appear to have been the only predators that might 
have affected the rails. But. from their abundance, 
the birds seemed to encounter no serious difficul¬ 
ties. Miller (1936:694) mentioned in December 
1935 “a never-ending battle between the flightless 
rails, the rats, and the hermit crabs. Constantly they 
prey on one another." This was certainly' an 
exaggeration. Atkinson (1985) hypothesized that, 
because of their interactions with land crabs, birds 
on Pacific islands relatively near the equator may 
have developed behaviors that allowed them to 
cope better with the subsequent arrival of rats. We 
know that rails certainly preyed upon hermit crabs 
and rats may have also, but the cooperative 
breeding system and apparent intense parental care 
of the rails would have prevented much interfer¬ 
ence with eggs and young by crabs or rats. 
Rats, however, have frequently been implicated 
in the extinction of the Wake Island Rail. The 
Pacific rat was doubtless transported to Wake by 
prehistoric voyagers and its presence was first 
noted by the U.S. Exploring Expedition in 1841, 
by which time the rat may already have been on 
Wake for centuries. Several observations quoted 
indicate that in the 1930s, Wake Island Rails co¬ 
existed with rats, fed alongside them, resorted to 
rat burrows to escape from sun and heat, and that 
rails and rats were mutually “respectful” of one 
another in disputes over food. Human settlement 
brought an increase in food to be found by rats in 
human habitations and refuse dumps, and doubt¬ 
less resulted in increased population size of rats, 
but there is no evidence this had any deleterious 
effect on populations of rails. 
Vaughn (1945:27-28) considered the rats on 
Wake in 1938 to be “vegetation-eating.” Fol¬ 
lowing the war, Fosberg (1959) reported the 
observations of Fred Schultz who was in charge 
of pest control on Wake for the Civil Aeronautics 
Administration. Rats had been reported in sleep¬ 
ing quarters and a dining hall, but Schultz “found 
that they hved largely in the clumps of bushes 
especially those which were covered by tangles of 
the wild white morning glory. Iponwea tuba. ’ ’ He 
found they used the enlarged immature fruiting 
