The Bird-House for Purple Martins 



By THOMAS L. McCONNELL, McKeesport, Pa. 



THE problem of designing a good house for a colony of Purple Martins 

 is simply a matter of attending to many little details. When a Martin- 

 box is deserted after two or three years the cause is apt to be one of the 

 following: Improperly designed house, uninviting situation, such as too near 

 or under trees, or too close to a fence or building, a poorly selected pole, the 

 Sparrows may have been allowed to take possession of the quarters, the small 

 boys may be persecuting the birds, or the place may not be cheerful. 



The bird-house should have at least ten separate rooms, for the sociable 

 Martins love to live in colonies and small colonies suffer much from the English 

 Sparrow. Make the rooms about 6 inches wide by 8 inches deep by 8 inches 

 high. There is really no exact size necessary. For instance, one authority 

 suggests 5 or 6 inches wide and of similar height and 8 or 9 inches deep, the 

 long rooms being favored so that the Screech Owl cannot reach the nests. 

 Another writer recommends rooms 8 inches wide by 8 inches deep by 6 inches 

 high. 



The doors may be 2% inches wide by 3 inches high, including 2i lyi inch 

 radius arch at the top, or round holes 2^ inches in diameter. A round hole 

 or arched hole should be made 'bulging' or become wider towards the center of 

 the box. "Even so small a change as boring a bulging hole in a box, instead of 

 a straight one, and beveling the lower edge of the entrance hole, increased the 

 occupancy of the boxes in the Berlepsch woods from 50 to 90 per cent." It is 

 better never to use a square hole and when one is cut, by all means round 

 off the top into an arch. Birds seem really to prefer a round hole. 



Two of the large, successful Martin colonies in McKeesport dwell in houses 

 with each room having two circular entrances about 2^^ inches in diameter 

 placed about i inch apart. This seems an excellent idea and the writer has 

 noticed that the old birds, when feeding their young, use both holes and dart 

 in and out with less confusion and interference than when only one opening 

 is provided. These entrances should be on the same side of the room and never 

 on different sides, as this leads to fighting among the old birds and spells 

 disaster to their eggs and young. 



Porches, about 2 to 2>^ inches wide must be provided in front of the doors 

 for the convenience of the old birds when feeding their nestlings and for the 

 young when they are ready to learn to fly. If there are no porches many young 

 birds fall to the ground and are lost. When a nestling unable to fly drops to 

 the ground it must be replaced on the box because the parents never feed their 

 young on the ground and, moreover, cats are usually on the lookout for such 

 accidents. By a suitable and artistic selection of porches the house may be 

 made a structure of beauty and grace. 



No ventilation is necessary besides the entrance holes and all rooms should 



(75) 



