THE BROWN-BACKED PETREL. 
Breeding-season. September (Mokohinou Islands, Sandager) ; October (Hautura Island. 
Reiscbek). 
Mr. Reischek* gives the following account of them on Hautura Island : “ They 
come ashore in September, to clean out their burrows or make fresh ones, which 
they accomplish by digging with the bill and extruding the refuse with then- 
feet ; they work during the day, and after sunset they leave for their ocean 
haunts, returning before sunrise. These birds breed in single pairs. The 
female hatches during the day when the male is generally out at the ocean, from 
which he returns after sunset, when the female leaves for the haunts, returning 
before sunrise, continuing this process till the young birds are a few days old, 
when both parents absent themselves during the day, but return after sunset 
to feed their young with an oily substance or matter which they disgorge into 
their bills. The young are full grown in March, when they leave the breeding 
resorts for the ocean. The adult bird makes a noise resembling the cackling 
of a fowl, especially before bad or wet weather.” 
On the Mokohinou Islands their habits are slightly different, as will be seen 
from Mr. Sandager’s accountf : — 
“ They lay in September in short burrows, the egg being easily reached 
without digging. No nesting-material, save a few feathers, is used. They begin 
to burrow in July, and do not work or remain in the burrow during the 
day. Some of the young depart at the end of December and the remainder in 
January.” 
BullerJ writes : “ They congregate in flocks, often of considerable size, 
and fly in a compact body, generally in a zigzag course, with a very rapid move- 
ment of the wings and not far above the water. Their flight is peculiar, too, 
in this respect, that they appear aU to turn at the same moment, like a company 
of soldiers, showing flrst the dark plumage of the upper surface and then the 
white under-parts as they simultaneously dip towards the water. 
“ Their habits are sociable, and flocks may often be seen in the daytime 
disporting themselves in the sea, making short flights just above the surface, 
then flopping into the water, splashing and chasing one another in their playful 
gambols, and when tired of their fun rising in a body, and rapidly disappearing 
from view. 
“ They seem to scatter at night. They fly low, but swiftly. Occasionally, 
perhaps once in several years, they appear in prodigious flocks.” \ 
The type-male figured and described was collected in New Zealand. 
* Trans. New Zeal. Inst. 1885, Vol. XVIII., p. 94, 1886. 
t id. 1889, Vol. XXII., p. 289, 1890. 
J Birds of New Zeal., 2nd ed., Vol. II., p. 237. 
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