Evening star., 1924-08-31

rate. robins. blue jays. cat birds and
some other species are seen in the
District of Columbia almost every
month of the year. The cardinal
probably either does not move south
ward at all or only for a brief period
in the dead of Winter. The mocking
bird is also here the greater part
of the year, as are some of the spar
rows and black birds and thrushes.
Experts Of the Biological Survey
of the Smithsonian Institution have
made close study of bird migrations
covering a period of "a years. The
movements of birds have been studied
by trained observers in all parts of
the country. including all species and
under all circumstances. The investi-
cation was started to settle the queS-
tion scientifically whether weather
conditions had any effect directly
upon the migration of birds. Then
the inquiry was widened to test out
other popular notions regarding birds
and was finally reduced to a serious
study of the causes which prompt the
birds to the Spring migration north
ward and the Fall migration south
ward. The results of the inquiry
may be summarized as follows:
Sometimes Make Blunders.
The birds nest at or near the places
where they are hatched, the female
bird returning to the same locality
during her lifetime. Due to the
tragedies in bird life, she often comes
in Spring with a new mate. The
Autumn and Spring migrations are
fixed by the semi-annual molting pc
riodS and have no relation whatever
to the approach of storms or other
| local weather conditions. The flight
of birds in their migrations often dis
| play a stupidity very far removed
from the superstition of any instinct
of the avoidance of unfavorable
weather.
Millions of birds have been killed
| in snowstorms. windstorms and heavy
rains in their passage over the
Northern Lakes and the Western
prairies. The fundamental cause of
bird migrations is the question of
food and conditions favorable to the
| nesting and care of the young.
II may be noted that bird migra-
| tions in the Fall take place at time
when food is most abundant and is
left behind. Yet if the birds should
remain the food would be exhausted
probably before Winter. so that the
general proposition that the birds go
South after a continuous food supply
is undoubted. Then again bird life
cannot flourish, even if it can survive
the rigors of the Northern Winter.
Bird life requires perpetual Summer,
and the songsters find it by migrating.
Migratfons Take Tolls.
The two annual migratioEs take
| large toll from the ranks of the fly
| erS. Storms destroy many thousands
| each year. Obsta cles such as high
| towers. big buildings and works of
art like the Statue of Liberty in New
York Harbor kill many. The Wash
ington Monument@and the radio tow
| ers at Arlington record many cas-
ualties. but the greatest destruction
| Of birds is brought about by the gun
| of the sportsman. Several species of
! the birds have almost been extermi-
mated.
| The wood pigeon, whose migrations
| once darkened the sky, is no more.
! Some of the ducks are gone or have
| become very scarce. Woodcock,
grouse, wild turkeys and the par
fridge are much less plentiful than
| formerly, and will be totally eXter-
minated if the shooting of them is
not halted. Scientists are of the opin-
ion that much of the increase of in
sect life and the ravages of the worm.
mosquito and fruit moths is due to
| the diminishing of the birds. The
| idea, has been many times advanced
that the balance of nature, between
harmful insects and tie birds. should
| be restored as a protection to garden,
| field and orchard