13 



^' . " 



Tin Cans, Flowerpots, etc. 



Till cans and flowerpots are not quite so suitable for nest- 

 ing boxes as are wooden receptacles, because pottery and 

 metal are good conductors of heat, and unless put up in the 

 shade are likely, in v^ery hot weather, to overheat the young 

 birds. Nevertheless, if such 

 utensils are placed where they 

 will be in the shade during 

 the hotter part of the day they 

 may be used with success (Plate 

 III). Cheap, thin boxes, such 

 as the larger cigar boxes, may 

 be fastened up inside a barn 

 under the eaves and a hole bored 

 through the wall of the building 

 into each box, or a box may be 

 made for this purpose (Fig. 11). 



Dimensions of Nesting Boxes. 



The following dimensions will 

 do for flat-roofed dwellings for fio. ii. 

 the birds named. These dimen- 

 sions are not absolute, but are such as seem to be popular with 

 the birds. The boxes may be made larger if desired, but not 

 very much smaller. The size of the entrance, however, should 

 not be changed. If the roof is not level but slopes forward the 

 back may be two or three inches higher. 



House Wren. — Interior dimensions, 6 by 3^ by 3^ inches. 



t' ■'..:,: 



• Box inside a building. 

 Biological Survey.) 



(From 



Entrance hole, | inch in diameter. Of course a wren will use a 



box with a larger entrance, and some people 

 prefer 1| inches, as they believe that the 

 wren can more easily carry the sticks of 

 which its nest is largely made through this 

 larger opening, but if the small entrance is 

 used English sparrows and other birds can- 

 not get in and molest the wrens. The long 



axis may be either horizontal or vertical and the entrance hole 



near the top. A miniature bird house (Fig. 12) will do as well, 



but takes more time to make. 



Fig. 12. — Wren house. 



