suggest the probable status of birds in a "normal", i.e., non-stormy, 
December survey in the last two years. 
2 
This December the diurnal survey was conducted for 73.6 hours over a 
* . ' - s -- 
• . . > 
distance of 678 miles (nautical). An additional 52.8 hours of nocturnal 
observation were conducted, 2.8 of which were spent drifting on the night 
4 
of 11-12 December. 
Bird density varied considerably from one area of the grid to another. 
Hence, for purposes of discussion, it is divided into quadrants (see map 
one) as was done last month. With the exception of the south quadrant, the 
relative proportions of resident birds in different sections of the grid 
remained similar in November and December. The south quadrant did show a 
considerable population increase* but this may not have been a very accurate 
index of its status as very little survey was conducted in the area this 
month. The sighting of one flock heavily weights the December figures and 
the quadrant density may well have been lower than our observations indicate. 
Perhaps the most noticeable change in avifauna since November is the 
complete end to the movement of transient migrants, i.e., Sooty and Slender- 
billed Shearwaters. Almost all the species observed were resident birds 
except the non-breeding Pterodroma from South America. Most of these petrels 
can probably be expected to remain in the central Pacific as the breeding 
population should have returned to southern waters by now. 
