Evening star. [volume] (Washington, D.C.) 1854-1972, 1927-08-07
PLANS BIRD CENSUS.
ON BROAD SCALE.
Or. H. c. 0berhoIser to Make
Count of Waterfowl in
~. 18 States.

How many waterfowl are there in
North America?
DIR. Harry {. Oberholser OF the
United States Biological Survey eA-
pects TO answer this question within
a 10 Der cent margin of accuracy
upon the completion of the first bird
census of the United States ever
taken, which starts this month.
DIR. Oberholser left Washington this
week to make the concluding ar
l'angements for this census in Is
Western States. The birds literally
will be counted rather than estimated.
At least 1000 census takers will be
engaged, and these will be stationed
at key points in the concentration
areas Of waterfowl. Notable among
these are the Chesapeake Bay region,
Long Island, the New England Coast.
the South Atlantic coast. the Gulf
region, the Great Lakes and consid
cradle areas of the Pacific Coast. The
work is expected to continue until
next January.
Concentration Areas Defined
The concentration areas for geese,
ducks and other waterfowl already
are known and defined. The Biologi.
cal Survey has prepared maps show
ing this distribution graphically. AT
least four-fiftl Of the North Amer
lean waterfowl winter in these areas
and at the two great migrating sta.
tons in Utah and Illinois.
Hence the work confronting the bird
counters is not so great as that of
human takers, because the area to be
covered Is not go great. There may,
for instance, be n few birds in West
~,,,s. 1,,& 50 fayry 4
is not worth while attempting a count.
There are some concentration areas in
Mexico. and the Biological Survey
hopes to send an observer there this
Winter. Eventually a census may be
taken of the breeding areas of the
North, but this would be a much more
difficult undertaking. For the pres
ent the Biological Survey will be sat
isfied If it car cover thoroughly the
concentration and migration areas.
Oberholser is an Export Counter.
DIR. Oberholser is an expert bird
census taker. On a single day along
the Potomac he has counted 100000
waterfowl. mostly canvasback ducks.
In making estimates of f1ocks of
waterfowl the usual procedure Is to
count those in a certain defined area
and then, using this as unit of
measure. to estimate the remainder OF
the flock. For this purpose units of
100 or 1000 are convenient. Such
counts can be made either when the
birds are resting or on the wing. In
the former case 1t is always possible
to check the estimate by determining
the number of square yards covered
by the flock and then determining the
average number of birds to the square
yard. with little experience" DR..
Oberholser says, "a counter reaches
q high degree of accuracy"
Where birds cover a. large area 1t
IL sometimes better, he says. to count
the number in considerable portion
of it and from this to approximate
the number in the total area. In
large mixed focks containing several
species Of ducks it Is impossible to
count the numbers of each species,
but the proportion OF the entire flock
made up by each may be carefully
estimated.
Each Flock Recorded Separately.
In making counts or estimates each
flock is recorded separately. as OBJ
served. and nothing Is left to the
memory. This is done because it is
difficult to carry in the mind, for any
length Of time, the exact numbers in
the successive f1ocks. Observers must
also be careful not to count the same
birds twice. The observers also have
been instructed to note whether the
birds counted are migrants or live in
the locality where observed.
Instructions have been given to
each observer to select the best area
in his vicinity. 1t should be extensive
enough to include large majority of
the waterfowl in the locality. For
practical purposes, however. it should
not be too large to be covered in
single day. Exactly the same area
should be covered every day of the
census.
The count will be taken each month
for the entire country. The Biological
Survey will supply the chosen dates
some time in advance, in order that
the observers can make the necessary
arrangements to get away from their
usual work. When this schedule is
broken up by storms another date
will be fixed within few days.
Observers Placed at Key Points.
Observers are being selected at key
points in the waterfowl country. At
will be used to provide workers.
These include the National Park
Service. the Lighthouse Service, the
Coast Guard, the Bureau Of Fisheries,
the Bureau Of Reclamation. the Office
Of Indian Affairs, the Bureau Of
Education, the Forest Service, the
Weather Bureau and the Extension
Service Of the Department Of Agricul-
ture. Sportsmen's organizations also
have pledged their cooperation, as
Rave conservation societies, State
game wardens and ornithologists.
The result Of the census may. have
an important bearing on legislation.
SO far. there has been no accurate
information available as to the number
of waterfowl in given area. Accur-
ate information, year by year, will
enable the Biological Survey to deter.
mine whether certain species are in
creasing or decreasing.
In case Of an increase game laws
will be hghtened, while II the birds