December 1948 The Queensland Naturalist 109 
species of birds, dramatic in its manifestations and one of 
the wonders of life which is not altogether confined to the 
avian world. Curiously enough, migratory movements of 
birds in the Southern Hemisphere, always excepting the 
great land mass of South America, are not nearly so evi- 
dent or extensive as are those of the northern half where 
the seas and lands of America, Asia and Europe present 
such diverse conditions of mountain, plain and stream, 
that a most intricate pattern of summer and winter migra- 
tion is a consequence. In the British Isles, the annual 
movement both north, south and east and the regular 
return movement during the other half of the year, is most 
extensive, both by day and night. Some birds visit Eng- 
land in the winter, journeying from the colder countries 
in the north . such as Scandinavia, Russia, Iceland and 
('ven from (ireeiiland. Others leave the British Isles a’ 
the same time, making for Southern France, Spain and 
Italy, whilst others like the swallows journey right across 
to Africa. Much careful study has been made of these 
-annual flights and this work has been carried out quite 
systematically in three ways. One by direct observational 
evidence, which deals with the mass movements of birds 
bv many watchers at widely different and carefully- 
selected vantage points, chiefly at lighthouses and at 
islands like Heligoland and other lonely islands round the 
coasts of England and Scotland. 
The second method is tin* marking method, which in 
England and Europe is carried out in an intensive and 
systematic manner. The third is by experiment, in which 
trial is made of various deliberate changes in the eondi- 
t nus (Tferting particular birds. 
Observation largely depends on opportunity. On the 
coast it is often possible to witness actual arrivals and 
departure. In favourable positions day and night, evi- 
dence of the vastness of bird movement in these regions 
can be obtained. The classic example of a migration 
observatory is the island of Heligoland, which, up to th - 
time of the last War, provided some wonderful accounts 
of mass movements of birds and was the scene of the 
life-long work of Heinrich Gatke. whose records were the 
first comprehensive data on this subject. Not the least 
aid to his study was the brilliant lighthouse that is in 
operation oil that island. At night time during the sea- 
