Vol. XII 

 1913 



Campbell, Report on Mullon-Bird Rookeries. 



273 



This, wc have proved to our satisfaction, is utterly incorrect, so 

 far, at least, as the Cape rookeries are concerned. Wc had 

 exceptionally good opportunities for examining the rookeries this 

 birding season. First, recent showers of rain had obliterated all 

 old marks, therefore the fresh tracks in and out of the burrows 

 made by the parents going to feed their young were easily seen, 

 and showed the burrows occupied. Second, early autumnal rains 

 had caused a fresh growth of grass and weeds at the entrance of 

 many burrows, therefore the empty ones could easily be detected. 

 A methodical count proved that approximately 62 per cent, of 

 the burrows were unoccupied, and were egged last season. Thus, 

 our suspicions beforementioned were fully confirmed. 

 The following are the details of our counts : — 



Details of Counts of Burrows * on Cape Woolamai. 

 I. — From Red Point to main headland of Cape — 



a. Open, bare ground near Banksia trees 



d. Another, ditto ... 



c'. Sword-grass sand-hill adjacent 



d. Ditto, not so dense 



IL — On headland itself — 



a. Open patch north slope ... 



d. Another (old thistle bed) ... 



6". Open patch south side 



d. Among Scirpus tussocks ... 



e. Ditto ... 

 /. Among Aster scrub 



in. — In large marram area fenced in (south coast)- 



a. Pigface rookery ... 



i). Ice-plant rookery opposite 



c. Another of same 



d. Tussocky brow of cliffs 



e. Another 



/. Among grassy hills with scrub 



,?■. Ditto, near fence 



A. Another 



i. Scrub at head of Pigface Creek 

 J. Another, ditto 



IV. — West end of rookery on south coast — 



n. Open ground 



d. Among sword-grass 



c. Very thick sword-grass 



884 1,416 



Of total of 2,300 burrows examined 38.4 per cent, only were occupied. 



* The number of burrows to the square chain is 260. This average was 

 obtained by six counts of separate plots each a chain square, selected in 

 different but typical portions of the rookeries. Presuming that there were 

 200 acres of rookeries, in a full laying season there should be about 

 1,040,000 birds. 



