Northern Prairie Wildlife Research Center
Elston H. Dzus, Nova Gas Transmission Ltd., P.O. Box 2330, Edmonton, Alberta T5J 2R1 Canada, and Robert G. Clark, Canadian Wildlife Service, Environment Canada, 115 Perimeter Road, Saskatoon, Saskatchewan S7N 0X4 Canada
The ability to remotely monitor body temperature allows the researcher to evaluate behavior and survival of an unrestrained animal under a variety of environmental conditions. Mallard ducklings are unable to effectively regulate their body temperature in the first week after hatching and thus require an external heat source during this period. We monitored brooding behavior and a correlate of body temperature of mallard ducklings under laboratory and field conditions.
Temperature-sensitive microtransmitters (1.1 g) were glued to the skin on the back of wild-strain, captive-reared ducklings using Skin-bond O adhesive. Four to 6 ducklings per brood received transmitters. Captive female mallards that had recently (<3 days prior) hatched their eggs were used as the care-giving heat source. The recording system was comprised of an omni-directional antenna and a telemetry receiver (modified to accept a voltage output to change channels) connected to a data logger (which served to store data and provide the voltage output to the receiver). The system was programmed to record temperature and change channels every 10 sec. Experimental protocol was developed and utilized primarily in a laboratory setting where ambient temperature was manipulated between 5 and 30°C. A video camera was mounted above the experimental chamber to monitor behavior of the female and young. The sensitivity and accuracy of the transmitters allowed us to easily record tenth of a degree accuracy for duckling temperature; such sensitivity allowed detection of when the duckling was or was not being brooded by the female (confirmed by the video recording). The system worked very well in laboratory conditions and limited field testing showed considerable promise for future applications under natural conditions.