NORTH AMEEICAN MARSH BIRDS 181 



the breeding season and acquire some rudimentary, white, plumelike 

 feathers on the back. Some other parti-colored birds acquire many 

 long, blue, plumelike feathers on the back, similar to those worn by 

 breeding adults. Both of these last two are probably breeding 

 plumages. 



I spent the winter of 1924 and 1925 in the vicinity of Tampa Bay, 

 Florida, where little blue herons were very common and constantly 

 under observation. Up to the time of my departure, on May 1, I 

 did not see, among the hundreds of birds examined, a single white 

 bird which showed any appreciable signs of molting into the blue 

 plumage, though I was always on the watch for them. Hence I infer 

 that the normal time of molting is in May or later. 



Apparently the first postnuptial molt begins in the spring; perhaps 

 the solid blue feathers seen in April birds show the beginning of it 

 but I have seen birds taken in July in complete fresh winter plumage. 

 This molt is complete and removes all traces of inmiaturity. I can 

 not agree with the two-color-phase theory; I have never seen a bird 

 in wholly blue plumage that was not unquestionably an adult. I have 

 never seen a white bird which was not unquestionably immature; the 

 whitest birds are all fall birds; the parti-colored birds are all spring 

 birds; and I have never seen a white bird in the fall that showed any 

 considerable amount of blue. The change from white to blue is pro- 

 gressive throughout the first year and no trace of it is seen afterward. 



Adults have the usual heron molts, a partial prenuptial molt begin- 

 ning in February, and a complete postnuptial molt beginning in 

 July; the wings are usually niolted in August. The long, "slate- 

 blue," plumelike feathers of the back, and the "Indian red" plumage 

 of the head and neck are characteristic of the nuptial plumage. In 

 winter plumage the head and neck are more purplish, with more or 

 less whitish in the chin and throat, and there are only a few short, 

 plumelike feathers in the back. 



Food. — -The little blue heron feeds to some extent in salt or brack- 

 ish waters in estuaries and coastal marshes, where it catches minnows, 

 fiddler crabs, and other crustaceans. But its favorite feeding grounds 

 are in fresh-water marshes and meadows, around the marshy shores 

 of ponds and lakes, and along the banks of inland streams. Its ac- 

 tive method of pursuing its prey has been portrayed so well by the 

 illustrious Audubon (1840) that I can not do better than quote his 

 words, as follows: 



There, and at this season, reader, you may see this graceful heron, quiet) and 

 in silence walking along the margins of the water, with an elegance and grace 

 which can never fail to please you. Each regularly-timed step is lightly meas- 

 ured, while the keen eye of the bird seeks for and watches the equally cautious 

 movements of the objects towards which it advances with all imaginable care. 

 When at a proper distance, it darts forth its bill with astonishing celerity, to 

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