BIED BANDING LINCOLN 329 



traction for these birds, and would frequently bring them to the 

 ground (pi. 1 and pi. 2, fig. 1). With this knowledge, progress was 

 rapid until now many stations are taking them in considerable vari- 

 ety and number. For example, a report recently received by the 

 Biological Survey, following the spring migration of 1932, contained 

 the banding records for 165 warblers of 19 species, while reports 

 from other points show similar success. 



Some of the author's early work in the field of banding had to 

 do with the development of a satisfactory trap for ducks. The 

 traps that had been used by market hunters were known, but gener- 

 ally these were found to be unsatisfactory for banding work. A 

 short period of experimentation, however, resulted in the perfection 

 of a simple trap that gave excellent results when used for mallards, 

 black ducks, pintails, and other shoal-water species. Success here 

 was somewhat discounted by the skeptics who openly declared that 

 it would be a different matter when operations were begun with can- 

 vasbacks, redheads, scaups, and other deep-water species. It was a 

 different matter, but already several thousands of these ducks have 

 been banded (pi. 2, fig. 2, and pi. 3, fig. 1). In fact it is now a 

 maxim with bird banders that " there is a way to trap everything 

 if you can only solve the problem," and " you can trap any species 

 for which you can discover an attractive bait." 



The smaller tree climbers, such as the brown creeper and the black 

 and white warbler, presented another problem. As these birds as- 

 cend the trunk of a tree it had been noticed that if they met any kind 

 of an obstruction, they generally flew to another tree. It was found, 

 however, that if the barrier slanted upward, the birds would continue 

 to ascend, keeping a short distance away from the obstruction. Upon 

 the basis of this observation, William I. Lyon, of Waukegan, 111. 

 (1924), worked out a highly successful trap for taking these birds 

 (pi. 3, fig. 2, and pi. 4) . A collar of wire netting, tacked to the trunk 

 of the tree in an ascending spiral, serves to guide the climbing bird 

 into the trap chamber. 



GAME SPECIES— WATERFOWL 



From the beginning of the project, the Biological Survey has given 

 all possible attention to the banding of large numbers of migratory 

 waterfowl, confidently believing the resulting data would be most 

 useful in its administration of this important natural resource. Table 

 2 illustrates in part the success that has attended these efforts. With 

 the data represented in this table available, valuable contributions 

 may be made to the problems of conservation. The following sum- 

 maries are based on studies already made or in progress. 



