36 
THE CONDOR 
V ol. XVII 
9. Oceanodroma leucorhoa. Leach Petrel. Leach’s Petrel is said by the 
natives to nest only on South Island, and this appears to be the case as no evi- 
dence of their dwelling places was detected during numerous excursions over 
Forrester and Lawrie islands. On the southern island, however, their name is 
legion. Almost as soon as a landing was made small openings were noticed in 
the moss covering the rocks, and while these appeared surprisingly similar to 
those made by mice a minute’s work was all that was necessary to disclose 
their true character. Others were half hidden in the grass and among the 
underbrush, and from the central valley to the summits of both hills the soil 
was riddled with holes. In various places from four to seven were counted in 
a . space a yard square, and one must tread cautiously indeed to escape break- 
ing through the burrows at every step. At the time of the first landing, June 
30, the birds living in the comparatively dry soil covering the rocks had com- 
pleted the clearing of the burrows and the building of the nests, and in most 
Fig. 17 . Burrows of the Leach Petrel on Forrester Island 
instances had deposited the single egg characteristic of the genus. In the 
underbrush the burrows had been cleared, the refuse material had been dragged 
to the front of the entrance, and the nests had been completed in many in- 
stances. However the breeding season is not sharply defined since a few fresh 
eggs were found on July 19 and 20. 
The burrow leads inward from the entrance for varying distances, two 
feet being about the average length. In extreme cases tunnels have been 
opened having a length of fully six feet, and from two to five birds occupy 
this in common, each nest being placed in one of the lateral offshoots from the 
main trunk. Such extensive residences have evidently been vacated by Cassin 
Auklets as one young bird of this species was found in a burrow with five 
petrels. The nest is a flat, thin pad composed of fragments of grass, bits of 
moss and small twigs of spruce or salmon berry. As is well known the egg is 
