Journal R.E. Johnson 1968 May 30 Amchitka Island, Alaska (cont.) buildings in area A & B are close together compared to the South Hanger area. In the latter area buildings were sometimes close together, but in one dimension only, suggesting that spacing alone is not the important factor, but total amount of adjacent land per pair is. The major function of this "land" would be Foraging. Though I have not measured the areas of the total A+B area & of the South Hanger area, it is obvious from the topographic map that the latter area is nearly 3 times as large. One would expect more nests in a larger area & this occurs (16 nests to 11 nests) but not to the extent predicted on the above analysis. The densities of buildings should also be figured when the area figures are available. As a premature analysis one might suggest that good nest sites are limiting in the South Hanger area (or else the site is poorer than area A+B) & that food limits density via spacing in areas A & B. Studies of food in the 2 areas would therefore be worthwhile. Since there were plenty of unoccupied nest sites, as I judged them, it appears that nest sites do not limit in either area. However rosy finches may see it differently. Against this is the fact that finches had built nests in 85% of the places I judged scutable in the South Hanger area, but