BUREAU OF BIOLOGICAL SURVEY. 285 



now that the heiieficial species are fortified by ample protective le<yis- 

 lation, the importance of perfecting methods for protecting crops 

 a^^ainst damage by birds becomes apparent. 



FISH-EATING BIRDS. 



Continuin^^ the work started last year in investij[^atincr the food 

 habits of fish-eating birds, field work was conducted in Florida to 

 ascertain the relation of pelicans to the fishing industry. Claims 

 had been made that these birds were responsible for the reduction in 

 the numbers of mullet noted in recent years, as well as for the de- 

 struction of other food fishes. It naturally followed that the pro- 

 tection of the brown pelican in the breeding colonies, which are 

 maintained as bird reservations, was criticized. The habit of young 

 pelicans, in common with some of the other fish eaters, of regurgitat- 

 ing their food when disturbed, permitted the examination of the 

 stomach contents of several hundred of them without killing a 

 bird. Of the 814 fish found in the material examined only 9 (7 

 mullet and 2 red fish) were of species valuable as human food. 

 By far the largest item, comprising over 91 per cent of the food, 

 consisted of menhaden, a nonfood fish occurring in great abundance 

 in the shallow waters about Florida and along the Gulf coast. Adult 

 pelicans, however, are at times a nuisance about gill nets, where, in 

 their attempts to secure the enmeshed fish, they tear the seines. 



Koports of destruction of trout by mergansers, or fish ducks, in 

 Michigan were investigated, but the mildness of the past winter pre- 

 sented conditions tending to keep these birds out of the smaller 

 streams where the damage is usually done. This matter must be 

 investigated under more nearly normal winter conditions to deter- 

 mine accurately the amount of loss from this source. A report on 

 the economic status of all our fish-eating birds is nearly ready for 

 publication. 



NIGHT HERONS IN LOUISIANA. 



In Louisiana the night herons had been charged with being :i 

 menace to the frogging industry, and for that reason permission was 

 asked to shoot them, as had been done prior to the enactment of the 

 migratory -bird treaty act. Louisiana is the only State wherein night 

 herons had ever been widely considered as legitimate game and a 

 source of food. Among the French-speaking people of some sec- 

 tions the young of these birds are considered a great delicacy, and 

 " gros-bec " hunting has been a favorite sport in the cypress swamps 

 of La Fourche, Terrebonne, St. Harys, and neighboring parishes. 

 An expert made a careful study of the birds in their haunts and 

 after examination of a large number of stomachs reported that these 

 birds are in no way a detriment to the frogging industry. It was 

 proved that more than 96 per cent of the food in the stomachs of the 

 night herons examined consisted of crawfish, and not a single frog 

 was found. These birds were mainly the yellow-crowned species 

 {Nyctanassa violacea)^ but previous examinations of stomachs of 

 the black-crowned night herons showed that they had similar habits. 



WHITE-WINGED DOVES IN ARIZONA. 



Complaints by grain raisers of Arizona against the white-winged 

 dove also necessitated investigation, chiefly in Maricopa County, 

 where about 30,000 acres of Avheat and barley had been planted. It 



