THE SEA BIRD LOCKLEY 343 



The shearwater nests in a hole in the ground, sometimes deep in 

 a rabbit hole, but it will also excavate a hole for itself in soft ground. 

 A small colony nested in shallow burrows within a few yards of my 

 back door. So it was not difficult for me to trace with a stick the 

 winding of each burrow to the nesting recess at the end, and to cut 

 out a turf immediately above the nest and then to use that turf as 

 a convenient inspection lid. I wish I could tell you how much 

 pleasure my wife and I got out of this acquaintance with the indi- 

 vidual bird. In successive seasons individuals returning to the same 

 burrows became almost tame and quite used to handling. Of course 

 we had to lift them out of the nest very frequently in order to note 

 the ring number by which we identified them as individuals. 



By degrees we were able to work out something of the Manx 

 shearwater's life history. The burrow would be inhabited as early 

 in the year as February, the paired birds meeting each dark night as 

 if they were determined to make sure of their nesting territory in 

 good time for another season, although laying does not take place 

 until late April and May. Ringing has since told us that the old 

 breeders always arrive first. 



There seems to be a shortage of desirable burrows. Ringing told 

 us that, in the absence of the legitimate pair, their burrow might be 

 seized by another home-hunting couple. We ringed these wandering 

 couples, of course, and found that they were moving from hole to 

 hole like the newly married in search of the ideal home. This spring 

 hunting was not without its comedies. We would surprise lovesick 

 couples trying to convince each other with much crooning — for that 

 is not an unfair description of the bird's powers of conversation — 

 that the shelter of an old box, a plank or some other inadequate 

 recess, was the real thing. But the light of morning would prove 

 that these places were not dark enough and the lovers would fly 

 out to sea before the predatory gulls and hawks discovered them. 

 Sometimes, too, we would find a bird of one pair, which we had 

 registered in our books as an established married couple, sitting in 

 its burrow with a strange bird, an unringed bird, or at least a bird 

 recently ringed as a newcomer to the colony. It was easy to interpret 

 this new bird as an interloper enterprisingly on the lookout for a 

 ready-made home, if not also a ready-made mate. This promiscuity 

 was frequent up to the time the egg was laid. We found that after 

 that date the pair which was properly registered, the pair which had 

 done the donkey work, if I may use the term, the digging and en- 

 larging and the nest lining, and performed the evening concert of 

 crooning, this pair settled down to incubate. The occasional visitor 

 now seldom or never intruded upon the domestic scene. Sexes are 

 indistinguishable in the field, but in some cases we knew the female 



