40 winks after lunch and after the UF arrived with the mail went up the Radar tower again until 1910 hours. For the past three days the weather has been identical, and now that we have worked out the bugs in the system, we will be able piece togeth- er data from days such as this to form the picture of activity for a particular kind of day at a particular time of year. One of the biggest problems in taking the data is standardizing the method of sampling, but I think that Bill and I have worked this out by taking counts every five minutes of every- thing aloft at that time, and noting in the meantime anything especial that occurs in the way of activity. This should elimin- ate the bias of the observer in taking readings when those birds which seem to him most active are up and flying. 10-26-63 After a long week of early risings we slept in and it felt damn good. Spent the late morning and early afternoon out in Petrel-Shearwater Study area A marking burrows. ( See Appendix 1, Page 1-D. ) I was very suprised to find out just how dense the nests are within this area: I had originally felt that there were 200-300 nests ( Active burrows ) in this area, but I think now that this is way low: In one-eighth of the area I located and marked 124 burrows, 79 of which had freshly thrown sand at their mouths indicating activity inside at the moment, and 28 surface ( Probably from roosting Bonin Petrels ) scrapes. From this sample, it would seem that within this area alone there must be 500 and 700 active burrows. This area is not, however, typical because I choose this as the place with the highest concentration of burrows on the island. Study area B is more typical of the whole island in terms of bird concen- trations. Nonetheless, there could be upwards of 10,000 pairs of Wedgetailed Shearwaters, 750 pairs of Christmas Island Shearwaters, and perhaps 4,000 pairs of Bonin Petrels on this island. If someone has suggested such numbers before today I would have suggested a straight jacket for him. But, now they seem reasonable and very possible estimates. Saw two Black-footed Albatross flying over the South-West end of the island at 1420, and from the surface of a fish regurg- itated by an Adult ♀ Brown Booby I recovered a ( larval ? ) nematode. Also, I checked the skeleton of the Tattler which I prepared yesterday, and found much to my consterna- tion that the rats had gotten to it and eaten all of the ribs, part of the skull, and most of the sternum. With no lab space, I hate to dry the skeletons in doors, but it looks as if that is the only tenable solution until we get some place to work once again.