BIRD LIFE OF BARTICA 95 



birds of a breeding colony, and the flocking and flight to 

 definite roosting places. 



For some unknown reason many birds were not satis- 

 fied to search for food near their nests or community breed- 

 ing places. This was particularly true of species which nest 

 in company. I remember the brown pelicans, which breed on 

 Pelican Island in Florida, regularly flew over great stretches 

 of good fishing area, to some chosen distant spot, perhaps 

 twenty to forty miles away up the coast. Caciques and other 

 tropical birds which breed in colonies have a similar habit. 

 Xot far from Kalacoon a colony of red-backed caciques had 

 been established for many years, directly over an Indian 

 benab. These birds flew inland diagonally up the Mazaruni 

 to some part of the jungle to which I was unable to trace 

 them. One could take one's stand along this route and be 

 certain within a few minutes of seeing a cacique going or 

 returning. The path was a definite one, over some trees, 

 beneath the top-most foliage of others, in one place through 

 an immense hoop-like loop of liana. This was quite differ- 

 ent from the food migrations which I shall soon mention. 

 These birds were carrying food, both vegetable and animal, 

 to their young, and only a firmly fixed habit of taking the 

 same path had perpetuated this unnecessary consumption of 

 time and energy. The sharp outlines of the aerial trail 

 frayed out in the vicinity of the colony, and birds approached 

 their nests at will. But a hundred yards away, all converged 

 sharply, focussing on the narrow pathway high in air. 



The roosting flights of tropical birds will ultimately 

 demand separate special treatment. I shall touch only upon 

 the habits of three or four species which roosted in the clumps 

 of bamboo near the river bank and close to the house in the 

 rubber plantation. The habit was as regular and inflexible 

 as any seasonal migration, and in those species which asso- 

 ciated in dense flocks, the birds seemed to lose all individu- 

 ality and to become imbued with a united flock spirit, which 

 influenced all simultaneously, synchronously, as one bird. 



