A Pheasant Nest Activity Recording Instrument

Abstract

Information on the exact time of the daily resting and feeding periods of incubating ring-necked pheasant (Phasianus colchicus) hens and the daily time of egg laying is rather meager. Leopold (1933) gave dawn and 4:00 p.m. as the times at which incubating pheasant hens leave the nest. Baskett (1947) found no definite time at which he could predict with accuracy that any individual hen would be away from the nest. He states that eggs were generally laid in the interval from about two hours after sunrise to two hours before sunset, or between the two daily feeding periods. Difficulty in obtaining accurate data is largely responsible for this lack of information. Direct observation of the nest can be carried on only during daylight hours and may cause desertion of the nest or abnormal behavior by the hen. The need for a method of automatically recording the daily movements of nesting pheasant hens was evident. A number of methods have been devised for recording nesting activities of song birds. Baldwin and Kendeigh (1927) described the use of a thermocouple and recording potentiometer to record nesting activities. The application of heat to the eggs registered the presence of the bird, and a drop in temperature depicted its departure. The thermograph could be placed in the nest with little difficulty, but the recording potentiometer required an electric current, a limiting factor in its use. Kendeigh and Baldwin (1930) detailed the use of an itograph, an electromagnetic device particularly adapted for use at nests with but one approach. Another electromagnetic instrument, the terragraph, was invented by a German, Count von Hegendorf, for studying the habits of foxes and badgers, and was applied to bird activities by Bussman (1933). The apparatus consisted of a paper dial-plate marked at half-hour intervals on a revolving disk, with a carbon paper on top. A pencil attached to a telegraph magnet pressed on the carbon paper when the circuit was made, making a short line on the paper dialplate below. Two small pieces of wood fastened at one end by a flat steel spring comprised the nest contact. The contact was placed in circuit by means of an insulated copper wire with two pocket batteries and the telegraph magnet. Kuusisto (1941) used a glass tube containing mercury and with one end expanded like a thermometer as a thermo-contact.