the band mumber incorrectly. In another series of 250 letters with no 
band included, the clerks had promptly spotted 5 numbers that contained 
an obvious error. The probabilities of plausible but erroneously reported 
numbers escaping detection vary from species to species. Among the mal- 
lard records that I examined most carefully, 0.5 per cent might be taken 
as a preliminary estimate. 
Table 4.--Factual Discrepancies in Fish and Wildlife Banding Cards 
Methods of Eliminating Discrepanc 
Chiefly Checking Checking Checking aripicat 
Discrepancy Machine Banders' Fiscal Recovery ‘eports 
Sorting Reports Yr. Rec'd Minor Error Major Error 
Pa Number Errors per LOOO cards 

Wrong species 0.5 1.5 - = ‘ 
Spurious record Lek 0.7 = 0.7? 0.7 
Wrong banding date 
Year 1.5 2.5 ~ - ~ 
Month or day - 33.0 - - - 
"How obtained guessed - - - 29.1 
ate of recovery 
Omitted in letter; 
guessed on card 
As "about" = “ - 7 
As “season'' 
Wt Or Cow 
MO O Win 
As definite date - - = 1 - 
Made tco definite - - - 15. - 
Wrongly transcribed 0.7 = Lely 13. es 
Banding age guessed - BO - - = 
Sex 
Missing on card - 20 - - - 
Conflicting data o = = 8.3 
Guessed by clerk = 1 - ~ = 
Wrongly transcribed - 7 - - - 
Questionable record 0.7 = = lek 
TOTAL 4.8 13527 1el+ 147 « St 2. le 
* Classification of major and minor errors depends in part on the use 
to which the recovery reports are put. For some investigators the source 
of a recovery report is of little interest, and the 29.1 guesses on "How 
obtained" would represent a minor error. The conflicting data on sex 
represents a type of discrepancy that might or might not be important. 
Clerical transcription of data.--In table 4 I have attempted 
to summarize discrepancies and errors of transcription or interpreta- 
tion on 2000 cards checked against banding schedules and 145 cards 
carefully compared with letters of recovery. This test was based on 
mallards banded by a single person, A. J. Butler, in British Columbia; 
it followed up a mech smaller test on 51 banders whose cards showed 
20 
