THE OWLS 



221 



are nocturnal and most birds diurnal, the chief food of according to estimates made by the Biological Survey, 

 the owl is small mammals and birds suffer relatively the loss due to prairie dogs, ground squirrels, pocket 

 little. Extensive studies of the food of owls made by the gophers, jack rabbits, meadow mice and pine mice 

 United States Biological Survey have shown a very small amounts to over 150 million dollars. House rats and 



house mice account for an- 

 other loss of over 200 mil- 

 lion, not including the loss 

 by human disease trans- 

 mitted by these pests. In 

 these days when the main- 

 tenance and increase of the 

 food supply is so import- 

 ant, the value of owls, these 

 rodent destroying machines, 

 cannot be over-emphasized. 

 It is not difficult to prove 

 to one's satisfaction what 

 the local owls are feeding 

 upon. All owls have the 

 habit of swallowing their 

 quarry, unless it be very 

 large, entire, fur, bones, 

 feathers, and all. If very 

 large, it is torn into a few 

 pieces and these are swal- 

 lowed. The stomach di- 

 gests out the flesh, rolls up 

 the bones and fur into neat 

 oval packets, and the bird 

 then disgorges these in the 

 form of pellets. Anyone 

 familiar with the places where owls roost knows of 

 these pellets. An examination of them as shown in the 

 accompanying photograph, shows a large percentage, 

 if not the entire food, to be small rodents. 



The migratory movements of some owls make them 



the more effici- 

 ent protectors 

 of our crops 

 for they move 

 from place to 

 place, seeking 

 abundant food. 

 Particularly is 

 this true of the 

 short-eared owl 

 for every time 

 that meadow 

 mice become 

 unusually 

 abundant in a 

 loc a 1 i ty and 

 threaten to be- 

 come a great 

 pest, a flight of 

 these owls us- 

 ually follows. 

 They remain in 

 the infested 



percentage of birds or poul- 

 try in the food of any 

 species, the great horned, 

 excepted. They are, there- 

 fore, among the most ben- 

 eficial birds that we have, 

 for it is absolutely neces- 

 sary that some check be 

 placed upon small rodents. 

 Take the meadow mouse 

 as an example. This little 

 animal has from five to 

 eight young in a litter and 

 from three to six litters a 

 year, or from 15 to 50 

 young annually. If the 

 number of young each year 

 were only 15 and they 

 should go unchecked for a 

 time, at the end of five 

 years there would be over 

 75,000 offspring from each 

 pair. It is not necessary 

 for each one of these 

 small rodents to do much 

 damage for the aggre- 

 gregate to be unbearable, 

 normal number sometimes 



MOTHER NATURE'S MOUSE TRAP 



The short-eared owls are migratory and always appear in flocks where 

 meadow mice have become unusually abundant. They remain until the 

 mice get_ scarce. Nature has taken this way of preventing plagues of the 

 prolific little rodents. This is a wounded short-eared owl. 



The destruction which a 

 do to young fruit trees 



or to grain in the stack often amounts to thousands 

 of dollars. Where unusual numbers assemble because 

 of an abundant food supply or successful reproduction, 

 the damage 

 done is stu- 

 pendous. I n 

 Australia, dur- 

 ing the present 

 war, when it 

 was necessary 

 to store grain 

 in the open or 

 on wharves, the 

 rats and mice 

 gnawed the 

 sacks, and what 

 was not lost by 

 their eating or 

 spilling was so 

 defiled that the 

 loss amounted 

 very quickly to 

 thousands of 

 dollars. Every 

 year in the brothers and sisters but no two alike 



TTnitpH ^rar^c Owls are birds of character and they show it from infancy. Each one of these young screech owls has 

 UIUICU ouues, hjg own opinion of thr photographer. 



