Nesting Habits of the Spotted Sandpiper

Abstract

IT certainly came as a great surprise to find that out of over eighty species of sandpipers and plovers treated by Bent in his 'Life Histories of North American Shore Birds, Order Limicolae' (Bull. U. S. Nat. Mus., no. 146, pt. 2, pp. 78-97, 1929), the Spotted Sandpiper (Actitis macularia) held the lowest incubation period, namely fifteen days, no other species having less than seventeen days, and only two I think at that, all the others ranging from twenty-one to twenty-eight days. In a paper on the 'Diving Habit and Community Spirit' of this sandpiper published in 1920 (Canadian FieldNaturalist, vol. 34, pp. 96-97,1920), I drew attention to the little we really know of the very intimate home life and traits of even the commonest birds, as only just lately had the incubation period of the Common Sandpiper (Tringa hypoleucos) of Europe (a first cousin to our Spotted) been ascertained to be twenty-one days. It was only in 1935, that the opportunity came to me of going into this matter with regard to our Spotted Sandpiper, for in that year I was fortunate enough to find two nests in the making, and to note the date of the first egg laid in each case, besides obtaining pictures of the hatching of the chicks, their hiding, and the parent brooding them. Both these nests were very carefully watched, and in each case the young hatched out on the twenty-first day from the laying of the last egg. This past year (1936), I had hoped to find these birds back on their old ground and to corroborate my records still further. Only one nest, however, was located on June 14 (twelve feet from the site of last-year's nest), but unfortunately it contained four eggs. From the actions of the parent as it flushed from the eggs (I shall refer to this later), I think it had been incubating a few days. These eggs hatched out on June 30, so even in this case I had watched the incubating bird for sixteen days, and feel sure I could safely add another four or five days, as the parent when flushing resorted to the so-called 'injury-feigning' trick, as seldom done unless incubation has been in progress a few days; as a rule the bird merely contents itself with quickly running off the nest, without any demonstration, if the set of eggs is incomplete, or quite fresh. When flushing, not only the smallness of the parent, but its behavior, put into my mind two thoughts: (1) Was it the male that was incubating? and (2) Why not pay especial attention to Dr. Friedmann's theory regarding this so-called 'injury-feigning' trick? With these two thoughts in mind, I paid frequent visits to the nest, in all about a dozen on different days before the hatching of the eggs. The nest