The evening herald. [volume] (Albuquerque, New Mexico) 1914-1922, 1915-08-27
MYSTERIES OF
BIRD

many thinss about the history OF our
J globe OF which We have oniy an In
%fcrcntial knowledge. Bird migration
lone OF the most impenctrablo mys-
teries Of terrestrial Hfe-may be a dl-
rect result OF the invasion Of ice in
the glacial ages.
When the bobolink. for nstancc
quits the New England fields with the
oncoming OF AUTUMN and goes ts
south America 20 pass the winter. or
rather not lose the summer he is
obeying an impulse COME down to
him Through generations of his aalces-
tors from the time when their orig
inal northern home began 10 lose its
permanently genial climate. such az
least. Is one 81 the most suggestive
theories invented 70 explain bird mi-
grafton
As She ice gradually pushed farther
and farther southwark its advance
edge swung back and forth with the
suusuns. and the birds acquired "a
habit OF retiring and returning Ia "a
similar swing. Finally they were
driven entirely from their old north
crn haunfs. But with the end Of the
last glacial period the favorable cone
ditions returned IN the lands tom.
which they had been expelled and
they resumed possession. Bat then
the habit OF seasonal migration hud
become so fixed hat % was pcrma-
ncntly retained. even in cases where
Il might ave been abandoned, and
the discovery having been made. un-
der compulsion as IL we're, that sum
mer conditions can always bc obtain
ed By passing 80 md hom across the
equator. his became the settled g
tom OF many species Of birds, whore
sole home had once been In the north
A dramatically opposite theOSy
assumes that the original home was
in the south. but in either case the
GLACIAL periods are regarded as hav-
ing furnished the motive for migla-
lion.
The results Of tbs most extensive
study o. blrd migration that has set
been made are embodied 800 1 recent
bulletin oi the hioiosicsl survey ut
the department Of agriculture The
phenomena OF migration would be-
more spectacular and better known o.
most OF the birds dls not connne their
blight to tbe nieht hours. When ucnr-
Us an the world arouisi them is asleep
they ny silently for hours through IN,
darkness. one uf Che meet remArk
able conclusions u- the ululogieal nu-
rcau is hat mi-rstug birds pHt 300
attention Go the weather W choosing
tine umc OF their departure IhH iu-
pulse seems Go come iroW within ana
10 be due to phE slulUeicul causes rec
lated 90 the period OF breedlut.
Few birds put themselves iY hlsh
speed during the migration li-nt
They go such moderate W.t'u".- at
twenty. thirty and forty miles @ days
making many side cNgurr.uu- TOR
food which increases thp a.L.Hl space
uayDrscd. But some specie WIAe
louu continued % rapid iI-lf
some make the trip across tn. '1I.
1t MoNicn. varying ln dist n.. accord
ue tO the route from 900 p" 400
miles boz "a siuslC tr.l. THE pafIl
martin is said tu average H.. mllD
every uisht boz its sprnr trp 'fou
lTczus % NIuuiprs
But whether they travel fast or
stow mnuy birds cover .rd. n'
lmiIrs In each migration n.rth ..
lsauth Tho brilliant ..I.r. tIHaa.I
H spends hlIr th, s.Hr 200 tIe United
- states lrd Clual1 uuu tu' utr.I AH.l
u Peru. Nor, tt.u H U" .l.. FI
p.es uf birds seen .u fHu lHr.l -I1u
Loo summer goo tn Central ..' South
% AmcriC4 for Tire WirtDl STONY 300
r. AS far as Argentine. and 90 l'" ae jag
, as Patagonia.
|Blach-pou Warbler. whose .rD,d.ue
9 nests are in Aiu... spend IH ".Hi.
q in the northern uarf ui r..iH AHn.'.
& lea. 5000 miles away. SOME "i IN'
, might hawks summer boz Altt"A a..
winter leo Argentina 1000 uIr
p |apnrt. some of the shore Hlfdf ha'.
even longer migration routes ih" coy
therc the Arctic tern iH tt' champion.
~ passss the fummcr us Gas uuitn %"
any land exists. ana tho winter on ih'
sd,p of the Anatrti. oouii". nt.
|lIaer. 1000 miles apart
a curious fact arising lI'ni lH' l''
& gauur OF Its home WltHln iN' pom.
circles That as W w '.Ih. i''
author ~ Iho bulletin HH".. ''i'I'.
CO.. t "TuD Arctic tern H' N'''
hours OF da.Iuaht and s. i'.'
.iany other animal ou tht ..'
ltbe nurtherumu.t resting til' iNt NNi'
Ipteht sun ha. already appt#r.H before
me bird arrival auu BE- netri s'lh H"i
ipV their entire stty 90 th, ur''dlI-
sroynds. ON the other hand. dufihh
100 months of their solouru il th'
A%ptnrrtic abe birds do mot SEQ "a suh-
~ and for the rest ut the Time ih'
IL, aims only Nttl, was below lh'
,.,tigon and broad dsylight is con
-r,.,us The birds therefore nay
p "a bonrs az daylight for ot least ciNh.
month";. and during the other l"Ni
O. wontbs have considerable more ahy'
tlHght than darkn'rs .
The longest continuous li'Rh' y s,,.
40 hc performed hy the gola'n tio'
e croesps from Noya fcotih l
America. a distance oi @io'
~nes in a straight line Ia i"u.
"en,ncr tbev sometimes mako q h'lI
% y, eermndn or IN the Antiias hu, I
mrather h. fair they do not -toI
III min hcy reach tho mainland
In south America. ON the F",ii'
slac oil the continent The golden llol
ler makes "a continuous thsh' "i -'''
,-nrvunllsig Alaska 10 hH""h' guy.
l~naturaiists wcpdsI now Nn'5 r.,
IT,. s,rtke 40 snsan "a maj tn tH'
E ~. or,natget Of oceans.