SAND DUNES AND SALT MARSHES 



ing his prey, then another series of holes, and 

 so on. Not so the iDlover; he strides along 

 with head up, but every few seconds he strikes 

 the sand a blow with his short bill for a minute 

 crustacean or worm below the surface. These 

 dabbings of the semi-palmated or ring-neck 

 plover are small, while those of the black- 

 bellied plover are large and are usually two 

 or three feet apart and generally double, 

 which means that the eager bird struck the 

 sand with bill partly open. The footprints 

 show three toes wide apart. 



At night the beach is often lined with night 

 herons, and their tracks, as w^ell as those of 

 their much larger but less common relative, 

 the great blue heron, and also of the small 

 green heron, are easily recognized. 



When the herring gull alights on the beach, 

 both feet come down together, or nearly so, 

 with considerable force, and thrust slightly 

 forward, as is shown by the deep impressions 

 in the sand at the back of the track. Occa- 

 sionally the birds strike so flat-footed that the 

 tarsus cuts the sand like a long hind toe. 

 Their webbed footprints sometimes cover the 

 sand thickly for many yards, with here and 

 there a pellet of fish bones, and with feathers 



64 



