Jan., 1914 
11 
NOTES ON THE DERBY FLYCATCEIER 
By ADRIAAN VAN ROSSEM 
D JUING the six months between February lo and August i, 1912, while 
collecting in the little republic of Salvador on the west coast of Central 
America, it was my fortune to make a more than casual acquaintance with 
the Derby Flycatcher (Piiangus siilphnratus dcrbianns) . Though extensive notes 
were taken on the birds themselves there are many points in regard to incuba- 
tion, care of the young, etc., which, in the pursuit of other equally interesting 
species and frequent change of collecting ground, were passed over, 
Aside from the .superabundant and ever-present Black Vulture {Catharista 
atraia) or ‘CSope” (which name, by the way, is occasionally given to the priests 
because of the merely external resemblance), no bird is better known by the na- 
tive population, or more quickly noticed by even the most disinterested visitor 
than the strikingly colored and noisy “Chio”, not so much because of the abun- 
dance of the latter birds, but because with the exception of a few Nicaraguan 
Boat-tailed Crackles {Megaquiscaliis nicaragiicnsis subsp.?) or stray Giraud 
Flycatchers {Myiozetetes tc.vensis texensis) they are practically the only small 
iTird to be found inside the larger towns. Though noted in greater or lesser num- 
bers in every locality visited, from the top of Volcan de San Salvador to the man- 
grove swamps along the coast, the center of their abundance is the highly culti- 
vated district surrounding the two largest cities, San Salvador and Santa Ana, 
which are situated at about two thousand feet above sea level. Toward the two 
extremes of altitude (sea level and 7000 feet) the birds become. scarcer ; decidedly 
so in the mountains and to a much less degree at the coast. At Acajutla, the port 
of entry, they were quite common. The intermediate zone is, as has been men- 
tioned above, under intense cultivation, but at the same time is criss-crossed and 
cut by innumerable steep-banked gullies varying in depth from a few feet to over 
a hundred, most of the larger ones containing water, and all, of course, hung with 
a tangle of tropical growth. Some of the narrower of these gullies are complete- 
ly arched by trees growing on the rims. These ravines together with the tiny 
‘‘fincas” or farms placed on the ridges (sometimes half a mile wide) between, 
make from a Derby standpoint an ideal breeding locality, as proven by the pres- 
ence of numerous nesting pairs. At a lower elevation where the more open coun- 
try is given over to cattle pastures they are also very common but do not seem to 
nest, as a general thing, so close to the ranch houses as in densely populated sec- 
tions. These birds -were found in considerable numbers, too, around Fakes Tlo- 
])ango and Chanmico. 
At the time of my arrival Derby Flycatchers were already paired off, but it 
was not until the first week in March that nest-building in the vicinity of San 
Salvador at least had commenced. The first nest which came under observation 
was about half completed on the 15th and was collected with four fresh eggs on 
the 28th. In this instance, then, nearly a month must have been required to build 
the nest and lay the full complement of eggs. Perhaps this time is unusually 
long, but as all that were subsequently found were already occupied at the time 
of discovery there was no means of determining this point. 
A wide variety of nesting sites is chosen. Near San Salvador where 
cocoanut palms are abundant these are generally selected, the nest resting on one 
or two of the lower fronds at their juncture with the main stem. Ordinarily a 
rather short palm is used, an average height being, say, twenty feet. The lowest 
was a scant six ; the highest a good fifty. In the lower country a small mesquite- 
