346 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1939 



land, of which they have perhaps unpleasant memories of hunger 

 and thirst. When a gull has swooped at a young shearwater so 

 released by us, the shearwater has simply dived deep and swum 

 away under water. 



Although we have ringed these young birds, for the time being 

 we have lost them as individuals. They have vanished into the 

 ocean (3). However, by ringing hundreds of them we are now begin- 

 ning to get some returns at sea of both adults and young. One 

 youngster ringed on Skokholm on September 1 got blown by a 

 gale into the Rhondda Valley 9 days later. That, of course, was 

 an obvious mishap. Another young shearwater took only 3 days 

 to get to the north of France, at St. Valery. We look forward to 

 more recoveries from large numbers recently ringed, and we are 

 expecting that the young birds will be proved to join up with the 

 adults, which wander as far south as the Bay of Biscay, and there 

 a good number of our breeding birds have been recovered (4) . They are 

 reported from various sources. French and Spanish fishermen shoot 

 or capture alive many kinds of sea birds. These men open the birds' 

 stomachs to find out what they have been feeding on. If the fisher- 

 men find edible fish therein they set their nets in the place where 

 the birds were feeding. Perhaps the most curious recovery was that 

 of a ring found in the stomach of an angler fish caught from the 

 pier at Douarnenez, in Brittany. Now the angler fish weighed 40 

 pounds, so it was large enough to swallow not only a shearwater, 

 but even another fish which may have attacked the shearwater and 

 bitten off its leg with the ring attached. I say this because when 

 ringing shearwaters on the island at night we have sometimes found 

 birds with mutilated feet, the webs between the toes missing, and 

 even a leg severed at some point on the tarsus. An angler fish feeds 

 normally at the bottom of the sea, but it may have swallowed a sur- 

 face-swimming fish which had previously snapped the leg off the 

 shearwater. This is mere speculation, of course. 



Curiously enough, ringed shearwaters have been reported to us 

 from the Spanish coast as late as the month of May, when you would 

 expect them to be back breeding on Skokholm. But these appear 

 to be young birds 1 and possibly 2 years old, which are not quite 

 ready to breed yet. Certainly our old ringed birds are always back 

 in their burrows in February and March. But no shearwaters ringed 

 as nestlings have been recovered on Skokholm so far earlier than the 

 middle of July of the year following that of their birth. This sug- 

 gests that in the second summer these youngsters are only visiting 

 the island in order to familiarize themselves with the breeding 

 ground for future years. In confirmation of this we have found 

 young pairs with quite undeveloped breeding organs indulging in 



