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Volume XII March-April 1910 Number 2 
THE EFFECT OF NATURAL ENEMIES ON THE NESTING HABITS OF 
SOME BRITISH HONDURAS BIRDS 
By MORTON E. PECK 
WITH FOUR PHOTOS BY THE AUTHOR 
D URING some two years of scientific investigation in British Honduras, the 
writer had occasion to study somewhat the nesting habits of the birds of that 
region, and was strongly imprest as any observer might well be, by the 
great variety and ingenuity of the devices employed evidently to baffle the attacks 
of natural enemies. Considering the great abundance of food, the absence of de- 
structive storms, and other obviously favorable conditions, we might expect the 
birds of that section to be correspondingly plentiful; nevertheless, wdiile species are 
sufficiently numerous, individuals are much less so than in most temperate regions 
where the numbers have not diminisht thru the operation of artificial agencies. 
Taking these facts into account, we must conclude that enemies are far more 
abundant and destructive in the tropics than in higher latitudes, and that the 
struggle for existence is even sharper, tho of a somewhat different nature. Let us 
consider the subject more in detail. 
It would be but a moderate estimate to say that thru two seasons of observation 
by the writer one-half of the nests found while being built were robbed by natural 
enemies before the incubation period was half over. These enemies may be divided 
into four classes: first, predatory birds, which comprise a comparatively large 
proportion of the avian fauna; second, reptiles, of which species and individuals are 
extremely numerous; third, small mammals, of perhaps a dozen species; fourth, 
insects, especial^ several species of ants. These four classes differ greatly in de- 
gree of importance, the reptiles — snakes and lizards — being probably the most de- 
structive. 
As regards their structure and location, the nests of birds may be placed under 
four groups as follows: First, open above and supported from beneath, on the 
ground, in grass-tufts, bushes or trees; second, in cavities of trees, rocks or banks; 
third, open above and pendant from a horizontal branch or leaf tip; fourth, roofed 
