Morning journal and courier. [volume] (New Haven [Conn.]) 1848-1894, 1893-10-23
THE uIGRATI0N OF BIRDS.

Science as Vet Offers No solution.
At the recent meeting of the British as
sociation Canon Tristram read an interest
ing paper on birds, from which the follow
ing extract Is taken:
"On the solution of the problem of the
migration of birde, the most remarkable
| OF all the phenomena of animal life. much
less sid has been contributed" he said,
'by the observations of field nstnralists
than might reasonably have been expected.
| The observable facts may be classified as
| to their bearing on she whittier, when,
and how of migration, and after this we
may possibly arrive ST a true snswer to the
why. Observation has Sufficiently an
swered the first question, WHITTIER There
are scarcely any festhered denizsns of
earth or sea to the summer and winter
ranges, of which we cannot now point.
OF almost all the birds of the holosrcttc
| fauna we have ascertAinsd the breeding
places and the winter resorts. Now that
| the knot and the sanderling have been
successfully pursued even to Grinnell
Land, there remains but the cutlew sand
| piper of all 1.-The known Europssn birds
whose breeding ground is q virgin soil, to
be trodden, let us hope, in a successful ex-
| ploration by Nansen, on one side or other
of the north pole. Equally clearly ascer-
tanned are the winter quarters of all the
| migrants.
| "The most casual observer cannot fall to
| notice in any part OF Africa, north or
south, west coast or interior, the myriAdH
| of familiar species which winter there.
We hsve arrived at fair kno ElsdSe of the
when of migration. of the how, we have
sscertsined little. but very litile. The
lines of migration vary widely in different
| species and In different longitudes. All
| courses of rivers of importance form mi
nor routes. Consideration of sll lines Of
migration might seTve 70 explain the fact
i of North American straGgls-s, the waits
| and strAys which have fallen in with great
/ flights of the regular migrants and been
| more frequently shot on the east cosst of
Englaud and Scotland than on the west
coast or In Ireland. They have not crossed
the Atlantic, but have come from the far
north, where q very slight DETECTION east
or west might alter their whole course,
and In that case they would naturally
strike the coast of Norway, and 30 find
their way hithsr In the company of their
| congeners. 1t lie maintained that the
| height of flight Is sumo fifteen hundred 70
| fifteen thousand feet. There are two sps-
| cies of blue-shrost: one with its red breast
| patch IL abundant in Sweden in summer
but is Devrr found ia G-Emsny. except
most Rccid.n .ally: the other Is the com
mon form of central Europe. Yet both
are abundant IN Egypt and Syria, where
they winter. Hence We infer that the
Swedish bird makes its journey from its
winter quarters with scarcely halt, while
the other proceeds leisursly 20 its nearer
| summer quarters.
| uI have more thnn Crca sem rnvrIsds of
| swallows, martins, sand martins and, later
| IN the EeEson, Ewiftr. passing up the Jor.
dan valley and along the BukoA of Central
Syria. at 60 slight an elevation that l was
able to distinguish ST once that the fIghl
consisted of swallows or house-maTtins
This was in perfectly calm. clear weather
One stream OF swsllows, certainly no. lest
than quarter of a mile wide, occupied
more than half an hour IN passing ovel
ons spot, and flights Of house martins
| and then Of sand-msr;ins, the next dsy
, were scarcely lees numerous These fiighti
must have bsen straight mp from the Red
Ses, and may have been the general sssem
bly, of all those which had wintered in ess
, Africa. These flights were not more ihsr
one thousand feet bigh. On the othel
hand, when standing on the highest peal
on the island of Palma, sixty FIVE hundred
feet, with a dense msss of clouds beneath
|
the distant peak of Teneri6e, thir:eer
thousand feet, have watched hock ot
Cornish chCughs soaring above, Till a.
length they were absolutely undistirguish
able except With field glasses. As to tn.
speed with which the migration flights al,
accomplished, they require much further
observation. Herr Gstke maintains ths
goduits and plovers can fly at the rate oi
two hundred and forty mIles an hour %
and the late Dr. Jerdon stated that tn,
spine-tailed swift, roosting In Ceylon
would reach the Himslayas twelve hun
dred miles, before sunset. Certainly Ii
their ordinary flight the swift was the only
| bird he had ever noticed to outstrip an ex
press train on the Great Northern railway
sFThere Is still much scope for the ieiC
naturalist in observation of partial migrs
tIons. But why do birds migratei OBJ
servstion has brought to light many fact
which seem to increase the difficulties of
satisfactory answer to the question. Th
autumnal retresl from the breeding quar-
ters might be explained by want of sufi
@ Client sustenance a. winter approaches Il
d the higher lstitudes, but this viii not &C
count for the return migration In spring
g since there Is 10 perceptible diminution O
q supplies in the winter quarters. Th
q northwsrd movement of all the other
% must be through some impulse not yet IS
70 | ceItaineu. IN many Olutf instances II
+ not dependent on the weather q: the me
+ ment. This Is especially the case with &c
10 birds. Professor Newton observes the
d can be trusted as the almanac itself. For
10 weather or fair, heat or cold. the pufinl
d Fraterculs arctics, repair to some of thei
rs stations pupctuslly on q given day, as
their movements were regulated by cloc
st work In like manner, whether the sun
N mer be cold or hot, the swifts leave thei
ID summer home in England about the fri
Ia week in August, only occasional stragglel
e. ever being seen after that date. To So
re that migration Is performed by instinct
r no explanation of the marvellous fscult!
ID Il is an evasion of the difficulty. II
a. sense of sight cannot guide birds whic
ce travel by night, or span oceans or cont
tn nents In q single flight. In noticing G
q. the phenomens of migration there yet 7
,k mains q vast untitled region for the he
of naturalist. What Professor Newton tern
the sense of direction, uneonsciozsIy exc