150 BRITAIN'S BIRDS AND THEIR NESTS. 



feeding on the exposed mud-flats, the birds sometimes 

 rising to chase each other, or uttering hoarse, goose-hke 

 cries. When the tide is in, we may see them grazing 

 hke Geese in the meadows or on the moor, or find 

 them nesting all together, though each pair keeps 

 itself perceptibly apart. Inland haunts are occasionally 

 resorted to. 



In May the nesting operations begin. A suitable 

 rabbit-burrow is chosen, or a similar tunnel is excavated, 

 the situation usually being the side of a sand-dune or 

 of a bent-grown hillock. The tunnel is generally some- 

 thing between five and fifteen feet in length, and when 

 long is often very markedly doubled back on itself. 

 Exceptionally, holes in rocks or bridges or other con- 

 cealed situations are chosen. At the end of the tunnel 

 a slight nest of grass or similar material is made, and to 

 this a large mass of down of a pearl-gray coloiu" is soon 

 added. The eggs are creamy white, and may number any- 

 thing up to rather more than a dozen. Incubation lasts 

 nearly a month before the eggs hatch and the chicks can 

 be led to the water. The duck has been said to carry 

 chicks on her back at times ; but as a rule no such help 

 is needed, even in a walk of a mile or two. In some 

 districts a brood en route is often surprised in the 

 village street in the early morning, and one has been 

 recorded making its way along a railway line. 



Both in appearance and habits this species betrays 

 its affinities with the Geese. Some of these resemblances 

 have received passing mention already, but two others 

 may be emphasised. The Sheldrake resembles most Geese, 

 and differs from most species of true Ducks, in having no 

 very marked difference between the adult plumages of the 

 sexes. It is true that the difference is sufficient to 

 distinguish the birds in the field; but it is trifling 



