pete OU ba Ne eB Ua Lae. Tot N 5 
year. If we all accumulated these records for each species year, we would 
be able to make annual comparisons of the migratory timing of each 
species; we might also be able to determine the relative abundance of 
some species by the number of reports received. 
Other similar information, which can and should be obtained, in- 
cludes the latest date (and respective location) each species is seen in 
the spring and the inclusive dates of the peak migration period: (that 
period when the majority of individuals of a particular species pass 
through ). 
In addition, all of the information obtained during the spring 
migration should also be recorded during the fall migration (arrival, 
peak migration period, and departure dates with locations). Only a few 
people presently keep such records. That is why there is only a limited 
amount of information available about the fall season in comparison to 
that of spring. 
Initially, for this program, Illinois has been divided into 18 Districts 
with county lines as boundaries (Figure 1). The districts have been 
designated in somewhat of a tier fashion, according to some prominant 
geographic features, and around known areas of existing Audubon So- 
cieties. [he Districts may appear rather large, but, at present, 1t would 
be inappropriate to make them smaller. 
Some Districts, as presently designated, have few active birders and 
cannot be further subdivided. As time progresses, it may become appar- 
ent that the Districts should be made smaller. County lines will probably 
still be used as boundaries between Districts; therefore, observers may 
desire to maintain county records rather than District records from the 
very beginning of this program. However, for present purposes, such 
county records will be referenced to the appropriate Districts (but will 
remain as county records in the file for future references and compari- 
sons ). : 
Soon, each will have an active, competent observer as District 
compiler to whom all records for that District will be sent. This compiler 
will be responsible for organizing the data for his (her) District and 
submitting it for the final statewide compilation and report. [he com- 
pilers will be announced later. At all times, the major contributors will 
be acknowledged. As expected, any unusual observation must be docu- 
mented (this will include exceptionally early arrivals and late depart- 
ures ). 
A few reports have already been received for the 1971, 1972 and 
1973 spring migration seasons. Our 1973 Spring Arrival table shows 
data reported only during this last season. The date in each column 
indicates the earliest date each species was first noted in that particular 
(continued on page 8) 
