THE CKOW AND ITS RELATION TO MAN. 7 
Jersey at Hainesport, Merchantville, Beedy Island in the Delaware 
Hirer, Bridgeboro, and Centerton; and in Pennsylvania at Davis 
Grove and Camp Hill. Some of these roosts are still occupied and 
are said to harbor thousands of birds. A roost at Woodridge, near 
Langdon, D. C, which appeared to be the successor to that observed 
some years ago at Arlington, Va., is reported by A. H. Howell, of 
the Biological Survey, to have harbored 270,000 birds in the winter 
1910-11. Mr. Howell estimated that fully 100 crows a second en- 
tered the roost at the height of the influx, and added that this would 
be 6,000 every minute, and if the same rate continued for three- 
quarters of an hour, which is about the time occupied by the gather- 
ing of the clans, 270,000 crows would be established for the night 
within an area of 5 to 10 acres. He says that while this estimate 
may be short of the actual number it certainly does not greatly ex- 
ceed it. Dr. S. D. Judcl observed this same roost in February, 1901, 
when he estimated 100,000 as its population. 
A roost located near Chevy Chase, Md., considered to be the suc- 
cessor to the Woodridge roost, and one upon which the writer made 
observations, gave a much smaller number of birds. Observations 
made on January 8, 1911, under a line of flight coming from the 
east, indicated that from 1,800 to 1,900 birds flew past. The four 
lines of flight entering the roost would probably give a total popula- 
tion of about 7,500. A strong wind was blowing at right angles 
to the direction of flight, and as this caused the birds to spread out 
in a pathway fully half a mile wide doubtless many were overlooked. 
About the 1st of January, 1912, the crows forsook this roosting place, 
and, again resorting to the previous site near Woodridge, combined 
with a small number which had been using this place. The writer 
visited this roost on January 28, 1912, and estimated the number 
coming from the north at about 6,500. This would mean that the 
whole roost was occupied by probably from 25,000 to 30,000. 
In response to letters of inquiry considerable information bearing 
on the location, size, and character of crow roosts occupied during 
the winter of 1911-12 was secured. Upward of 290 correspondents 
submitted reports of this nature, and while it can not be claimed that 
the data obtained are anything but a mere fragment of knowledge, 
the compilation of these facts sheds some light on the location of 
the winter crow population. 
On the map on page 8 (fig. 1) is recorded a total of 170 roosts of 
varying size. This shows in what areas a rather restricted migra- 
tory movement has assembled a large part of the crow population of 
North America. East of the Appalachians and grouped on the lower 
watersheds of the Potomac, Susquehanna, Delaware, Hudson, and 
Connecticut Eivers are many of the most populous roosts, some of 
