378 Norton, Notes on some Maine Birds. [oct. 



Black Tern is probably a nearlj^ regular fall migrant, it is seldom seen in 

 numbers. 



A remarkable flight was observed off Casco Bay, Cape Elizabeth and Saco 

 Bay September 5, 1913. The boatman with whom I took passage this 

 day, was a man very familiar with the appearance of sea birds, and he was 

 positive that he had seen them two days earlier. 



On the date above mentioned a large number of scattering individuals 

 were seen on the ground known as West Cod Ledge, and from here to 

 Bluff Island, a distance of fifteen miles. Besides these, one group of 

 twelve and more were counted off Richmond's Island. Six and more were 

 hovering over the surf on the north side of Bluff Island, and a flock of eleven 

 were seen flying to sea as we entered Portland harbor on the return home, 

 late in the afternoon. 



The birds were usually congregated over the drifting rafts of decaying 

 seaweed, floated from the shores, and at Bluff Island, they hovered feed- 

 ing, where the surf was washing the edge of a bank of this seaweed stranded 

 on the beach. 



Several specimens collected at sea, had maggots in their stomachs, 

 probably Coelopafrigida, which breeds on the beaches in the stranded and 

 rotting seaweed. 



A noteworthy feature of this flight was that it was offshore, few or none 

 of the birds being observed at the ponds by the sea where they usually 

 are seen. 



Oceanites oceanicus. Wilson's Petrel. — Wilson's Petrel has usu- 

 ally been cited as rare on this coast. 



My experience indicates that it is common at least from May 28 to 

 September 9, five or six miles offshore. During frequent excursions of 

 five to twelve miles offshore the past fifteen years, this is the only species 

 I have seen by day. It is a common occurrence to attract twenty to fifty 

 of these birds about a boat at anchor or slowly drifting, in an hour's time. 



If there is any breeze the birds are found flying to windward, and when 

 they find it desirable to work over a small space, after once passing over it, 

 they swing away in a large circle, and again come up from the leeward. 

 Birds showing peculiar conditions of moult, can thus be recognized, and I 

 have watched them for long periods of time, returning again and again 

 in the same manner. Thus a flock is composed of birds, constantly going 

 and coming, and while fifty are in sight, probably nearly as many more 

 are at hand, preparing to retm-n. On these occasions they are rather 

 silent, never noisy, but a low peeping note is often given, very similar to the 

 note of a contented young tame duckling (Anas platyrhynchos domestica). 

 Rarely I have heard them chattering, gutturally in a weak voice, audible 

 but a very short distance, in fact, neither note is audible (to me) for more 

 than a hundred feet in calm weather. 



One of the birds which I examined alive and unhurt, was unable to stand 

 upon its stilt-like legs, but rested on the tips of its toes and heel, i. e. tibio- 

 tarsal joint. I have several times seen them dive to the depth of about a 

 foot for sinking food. 



