Birds on Midway — Fisher 
107 
The rat problem is a continuing one and 
forms an important part of the third category, 
the after-effects of the war on the birds. As long 
as men were available and as long as the mili- 
tary authorities had sufficient reason ( other 
than birds) to keep the control program func- 
tioning, the rat populations were held in check. 
With the close of the war and the virtual 
abandonment (withdrawal of all personnel) of 
Eastern Island of Midway, the rats began to in- 
crease. In December, 1946, rats were quite in 
evidence on both Sand and Eastern Islands, but 
especially on the latter. Since the populations of 
Christmas Island Shearwaters and of Bulwer’s 
Petrels are small, and since at Midway they 
occur only on Eastern Island, they are in real 
danger of elimination. It seems probable that 
on Sand Island some sort of control program 
will always be in effect, but it is doubtful 
whether the numbers of rats will be reduced 
sufficiently to stop their depredations on birds. 
Other lasting effects of the war include the 
effects of acres of pavement put down for run- 
ways over the central parts of both islands. This 
pavement, as indicated earlier, covers the most 
heavily used breeding grounds of the Laysan 
Albatross, Wedge-tailed Shearwater, Bonin Is- 
land Petrel, Red-tailed Tropic Bird, and Sooty 
Tern. The area is lost for breeding activities. 
Macadam roads produce the same effect. It is 
true that Noddy Terns, albatrosses, shearwaters, 
and petrels have already moved back to the 
shoulders of the runways. Little-used coral roads 
through the Scaevola are being reclaimed as nest- 
ing areas by both species of albatrosses, but 
these nesting birds are liable to destruction by 
any passing vehicle. Many gun pits, foxholes, 
and other traps have been filled in, but some 
will no doubt remain for years. Buildings still 
cover many former nesting sites. However, for 
the most part the buildings are temporary and 
will simply disintegrate if they are not removed. 
Both species of albatrosses are now nesting in 
and around such buildings. 
In addition to factors which have worked to 
the detriment of the birds there have been a 
few, man-made, beneficial factors. Before the 
establishment of the Cable Station there was 
not much vegetation on Sand Island, and Eastern 
Island was called Green Island. The reverse is 
true now, due chiefly to the early (about 1906) 
activities of the employees of the Commercial 
Cable Company in planting ironwood trees, a 
coarse grass (Ammofthila arenaria ), and many 
other exotic plants on Sand Island. A nursery 
was established to provide further plantings. 
Pan American Airways aided in the work of 
planting Sand Island. The United States Navy 
planted sand-stabilizing grasses, as well as iron- 
wood trees, sea grape (Coccoloba ) , and tree 
heliotrope (Messerschmidia ) . Most of these 
plantings are taking hold well and in time those 
of the last 6 years will replace much of the cover 
that was destroyed early in the war. 
The effect of a greater amount of plant 
growth on birds is variable from species to 
species. There is little doubt that the presence 
of ironwood trees which provide many safe 
nesting places has increased the populations of 
Fairy and Hawaiian Terns. Bryan (1906), who 
visited Sand Island in July and August, 1902, 
found only 12 to 20 Hawaiian Terns, and long- 
time employees of the cable company say that 
Fairy Terns are much more numerous than they 
were 20 years ago. During the height .of the 
depredations by rats the Domestic Canaries took 
refuge in the ironwood trees for safer nesting. 
These trees are also used by the Domestic 
Pigeons, which are becoming numerous. The last 
holdout of the Laysan Finch was in the iron- 
wood trees and hibiscus hedges planted by the 
employees of the cable company. The Laysan 
Rail apparently made its last stand in the area 
around the exotic shrubs and lawns. This may, 
however, have been the result of better rat con- 
trol in this area, rather than any particular ad- 
vantages offered the rail by the habitat there. 
Perhaps the only species that would not bene- 
fit, and might be harmed, by additional trees 
and shrubs are the Laysan and Black-footed 
Albatrosses and the Blue-faced Booby, all of 
which need strips of open area for landing and 
