20 CLELAXD, Takhuj a Bird Census. ["^isffu^ 



— certainly as well as one might expect. If such double or triple 

 journeys were lumped as one, it would probably be the correct 

 procedure to consider, as the numbers of birds occupying the 

 area traversed, the highest number for each sj)ecies seen in any 

 of the journeys, inferring that the lower numbers meant that 

 some individuals had been missed. Another e.xplanation might, 

 however, be forthcoming, namely, that additional birds had en- 

 tered the area. As far as the results of this census are con- 

 cerned, we can look upon such out and return journeys as being 

 independent but ])arallel ones, traversing the same kind of coun- 

 try and corresponding l(j adjacent "traverses" in a forest survey. 

 It may be thought that during these journeys, birds are disturbed, 

 and, flying in front of the vehicle, may be counted again and 

 again. My experience has been that the birds usually fly off 

 to one or other side rather than in front, and that with ordinary 

 care it is only rarely that the same bird is counted again. 



The different districts in which the journeys were made have 

 been indicated by a]i)habet!cal letters as follows: — A. Broken 

 Hill district ( 1 ) ': I'.. Adelaide hills (2 + 1 return journey); C. 

 Sydney district ( 1 ) ; D. Eastern Ri\erina and South-Western 

 slopes, N.S.W. (6 + 3 returns) ; E. Western slopes and edge of 

 plains, N.S.W. (6 + 3 returns) ; F. Moss Vale district to coast, 

 N.S.W. (10 + 2 returns) ; G. North coast of N.S.W., from New- 

 castle to Tentertield — Lismore (24 + 4 returns) ; H. Scone dis- 

 trict (2 + 1) ; I. Boggabri— Narribri— Moree. etc. (21 + 5) ; J. 

 Brisbane district, (1 + 1) ; K. Dalby district, O. (1 + 1). 



\\'here a long journey has been made, for instance one of a 

 hundred miles by motor car, this has been split uj) for conveni- 

 ence into sej^arate journeys of twenty miles or so each, such di- 

 visions frequently corres|)onding with changes in the type of 

 country. Altogether 74 different "routes" have been traversed, 

 giving with the return journeys a total of 95 "journeys." The 

 distance travelled was ai)proximately 1329.1 miles. The shortest 

 "journey" was only half a mile, and the longest 60 miles. A.s 

 these journeys have by force of circumstances been of \evy un- 

 even length, it would be necessary before attaching the same 

 value to the figures for each journey, to reduce all to a common 

 standard, as, for instance, the number of birds ])er 100 miles. 

 Obviously space would not permit of this being done heie, and, 

 in the case of very short journeys, such a calculation might give 

 far too high a value for the species seen, and would ignore en- 

 tirely species in the locality which were not seen. 



As in some "districts" only one or a few "journeys" have been 

 made, and these perhaps short ones, stress must not be laid on the 

 absence from the census of certain species for such districts. 

 Thus onlv one short journey is tabulated for the v^ydney district. 

 The IMagpie-Lark (Gralli)ia cyatiolcuca), a common bird in the 

 neighbourhood, did not happen to be obser\ed. Had it been 

 seen, this species would have i)een observed in 9 instead of 8, of 

 the 11 districts. 



