Arrival Dates of Resident Birds 
In the consideration of the foregoing data one logically poses the 
question as to what percentage of the birds trapped in April may have 
migrated north by late May. Conclusive answers on this and the apparent 
occurrence this spring of two migration waves can only be answered by 
future returns of banded birds. 
It is well at this time to analyze the information gathered to date 
in this study which has a direct bearing on this problem. The results 
of a census conducted systematically twice a week on 3.8 miles of road 
in Quabbin Reservation by a special student is presented in Table 3 and 
graphically portrayed in Figure 1. 
In addition to this census Table )} presents the results of a census 
taken by R. T. Norris in Essex County near the northeast coast of the 
state. Although this is not as complete as the data presented in Table 
3 it provides additional data worth considering. 
It is noteworthy that after the height of migration between April 
8-10 there was a sharp decrease in the count in both areas, a condition 
to be expected. However, there was no evidence in either area of another 
build-up until after May 1. Norris's results in 1950 taken at different 
dates show little difference in the census count between April 13 and 
April 26. The highest count occurred on May 5. The same trend in 
population change which was noted this spring was indicated but in a 
less striking manner. 
A careful analysis of weather conditions eliminated weather as the 
factor which could account for large variations in the count (Table 3). 
Referring to Table 1 it will be observed that six recaptures from 
the spring of 1950 were taken before April 13 ad 5 of these were caught 
from the end of March to April 8 during the height of the migration. 
‘Although caught at a later date direct observation with binoculars on 
bird 50-3l5302 revealed a band on his leg tw days after his arrival. 
. He has returned to his singing ground the last two years on March 27. 
During retrapping this spring in late May none of last year's birds 
were captured which had not already been taken in April or late March. 
What fragmentary evidence there is indicates that males which bred in 
this area a year ago returned in late March or early April in the first 
influx of migrants. Further supporting data from Table 2 shows that 
seven birds banded this spring from the end of March to April 7 all 
were recaptured in late May. 
37 
