72 BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 



eminently seed lovers, and rarely eat anything else, except a few- 

 insects during the season of reproduction. The only mischief so 

 far imputed to them is the eating of the seeds of useful plants, such 

 as lettuce and other vegetables on seed farms. Investigation has 

 failed, however, to find a case where the damage was considerable. 

 The writer visited some of the largest seed farms in California and 

 ascertained that while birds, especially goldfinches, ate some of the 

 ripening seeds, the damage had never been serious enough to warrant 

 any protective measures. The writer observed goldfinches feeding 

 on lettuce seed, but the birds were few, and all they could eat would 

 have no appreciable effect on the quantity of seed harvested. 



One marked peculiarity of the goldfinches is their bibulous habits. 

 They seem always in need of water, perhaps owing to the habit of 

 eating dry seeds. The writer has seen more goldfinches drinking in 

 one day than he has seen of all other species in his whole life. 



Only 84 stomachs of the willow goldfinch were available for exami- 

 nation, but such is the uniformity of the food that a larger number 

 would probably not give a very different result. No stomachs 

 were taken in December, but all the other months were represented. 

 The food for those months amounts to 5 percent of animal matter 

 to 95 of vegetable. All the animal food was found in 10 stomachs, 

 9 being taken in March, April, and May, and 1, containing 2 larvae, 

 in September. Practically all the vegetable matter is seeds. 



Animal food. — The animal food was composed entirely of 3 orders 

 of insects: Bugs (Hemiptera), flies (Diptera), and caterpillars 

 (Lepidoptera). Bugs were contained in 5 stomachs and were all 

 plant lice (Aphididse). They aggregated a little less than 2 percent. 

 Flies were found in 1 stomach taken in April. They were in the shape 

 of larvae or maggots and amounted to less than one-half of 1 per- 

 cent. Caterpillars were contained in 6 stomachs and aggregated 

 less than 3 percent. Beetles, wasps, ants, and grasshoppers, which 

 so often constitute the bulk of the animal food of birds, are entirely 

 wanting in the stomachs of the willow goldfinch, as also are spiders. 



Vegetable food. — Vegetable matter appeared in every one of the 

 84 stomachs, and 73 of them held no other food. Hulls of oats were 

 found in 1 stomach taken in May. It amounted to 65 percent of 

 the contents of that stomach, and was the only thing of economic 

 value found in any one of the 84 stomachs. It amounted to less than 

 one-half of 1 percent of the year's food. Seeds of various weeds come 

 to over 91 percent of the diet, and are found in every stomach in every 

 month. For seven months weed seed constituted the entire food. 

 The following plants were identified: Centaur ea or bur thistle in 18 

 stomachs, alfilaria or filaree in 13, sunflower in 12, groundsel in 4, 

 mouse-ear, rust weed, and tarweed in 2 each. As the goldfinch takes 

 a good deal of gravel into its stomach, many of the seeds are ground 



