362 THE BIRDS 
their soft but short song, and reminds one of the nearness 
of warm weather. During the hard winter of 1912, 
January to March 15th, I picked up numbers of dead 
Bluebirds on my farm, showing clearly they are not a 
bird suitable for standing any protracted length of cold 
weather. During these cold spells many migrate further 
southward, returning with the first warm days of late 
March and early April. The Bluebird is less numerous 
than in former years. Whether climatic conditions or 
the extra settling of farm lands and more numerous cats, 
together with the restoring of old orchards, thus closing 
the natural cavities so suited for nesting sites, has played 
the most important part, I am unable to say. If all 
farmers and suburbanites would supply suitable nesting 
boxes or cans for them, protected from cats and snakes, 1 
think we could soon have them as numerous as formerly. 
